An OnScreen DNA Lite™ for iPad Gallery

May 4th, 2010

Apple’s iTune App Store provides one standard way (and place) for “apps” developed for the iPhone and iPad to be displayed. The app store listing is really a pretty good way to learn something about an app once you’ve managed to reach the page devoted to it. Apple lets developers describe the app in under 4,000 characters and choose up to five screen shots of the app for display in its listing. The screen shots are presented without captions, so they basically need to tell their lisinopril own story.

I chose the screen shots used for the OnScreen DNA Lite listing on the iPad app store with the aim of trying to show various features, but I think a little description could be useful, so I’m presenting here those same screen shots with some explanatory text. The dimensions of these screen shots have been squeezed down to fit into the blog column, so the area of the images is less than a quarter of the iPad display’s.

Here below is the thirty-five base-pair double helix of OnScreen DNA Lite’s virtual model. Note the row of control buttons at the top. The display mode is what we have called “Balloon,” which just means that the balls used to represent molecules in the DNA structure are substantially larger than they are in the “Skeletal” mode in which the double helix structure may be more apparent. The Balloon mode is closer to the “space filling” representations sometimes shown, but not so much as to hide the structure. Since Balloon cytotec mode is in use, the button that controls this feature reads “Skeletal” to indicate that a tap of it will shift to the Skeletal representation.

double helix

The sticks connecting the balls (molecules) in the model represent chemical bonds, which are less apparent in the Balloon mode. The model is shown above with “Tilted Bonds” (a button choice), which means that the sticks representing the glysosidic bonds between the deoxyribose phosphate molecules (white balls) and the nitrogenous bases (colored balls) are at an angle to the line between opposite sugar phosphates in the DNA strands. This propecia bond tilting is what causes the unequal spacing of the grooves (major and minor) that wind around the double helix structure. I expect to add a feature for making it obvious what these grooves are in a future update. The text in the panel above the image makes the point that the model with unequal grooves is more like the real DNA structure than the simpler model used priligy for the simulations.

Note that the bottom of the screen shots show the base sequences of the DNA strands of the model using the familiar letters GCAT (for guanine, cytosine, adenine, and thymine). The color coding is the same for the linear (letter) representation and the model.

The screen shot below shows the popover view that has the key to the model of OnScreen DNA Lite. It gives the names of all the molecules and chemical bonds shown in the model. Note that the phosphodiester bond has two parts indicated. The bond is shown with two colors to make it clear that there is a polarity to the DNA strands, and that they are of opposite polarity (“point” in opposite directions).

popover

The screen shot below shows the DNA model with one of the two strands hidden, which is accomplished by a button tap. This makes the helical structure of each strand apparent. Note that this shot is with the Skeletal mode selected. Natural DNA is right-handed, meaning that a strand circles around the axis of the helix in a clockwise fashion as it advances down the axis. This handedness may be easier to see with a single strand. To further make the concept of handedness clear, OnScreen DNA Lite also has the option to show what left-handed DNA would look like. In the screen shot the model has been rotated to the side and held there. This is easily (and satisfyingly) accomplished by a swipe of a finger on the iPad screen.

single strand

In addition to displaying the DNA model in various static (though rotatable) forms, OnScreen DNA Lite features a couple of simulations of phenomena that can occur with DNA in the laboratory. The first is denaturation, in which heating the DNA breaks the hydrogen bonds that keep the two strands joined together, thus allowing the strands to separate as single threads no longer bound to a helical shape. The screen shot below shows the two strands after denaturation has occurred, but the simulation that preceded it would have shown the strands being stretched and jiggled as the temperature increased, with individual bonds breaking until the double helix couldn’t be maintained. Note that, while showing that the hydrogen bonds are the most easily broken, an essential property for the functioning of DNA, which requires controlled strand separation at life-supporting temperatures (not the boiling temperature that brings on denaturation), denaturation is not a natural process occurring in living cells.

denatured

After the DNA strands have been separated in denaturation, it is possible (after the temperature has subsided) for them to recombine in the opposite process called renaturation. A few bases in one strand may come into sufficient contact with their complementary counterparts in the other strand to form a string of hydrogen bonds which can serve to hold the strands together long enough for other bonds to reform. This can be simulated in OnScreen DNA Lite after denaturation has occurred. The screen shot below captures an instant in the renaturation process after much of the double helix has been reformed, but before the process has been completed.

renaturation

Screen shots can be useful in getting a picture of what an app is like, but static pictures can’t really do justice to an app with dynamic simulations and with a model that can be rotated by touch. For the true experience you’ll need an iPad and the OnScreen DNA Lite app. But soon there will be a version for the iPhone and iPod Touch. For more on OnScreen DNA Lite for iPad see The Thinking Behind the OnScreen DNA Lite™ iPad App.

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The Thinking Behind the OnScreen DNA Lite™ iPad App

April 2nd, 2010

My first iPad app, now ready for sale on the iTunes App Store even before the iPad has gotten into many hands, is called OnScreen DNA Lite. Check it out! I plan to relate something of the hectic development of this app in a later post. Here my aim is to describe the iPad app a little and to motivate its development. The app is based on OnScreen DNA, a science education program I created a few years ago, first for the Macintosh OS X, and somewhat later for the Windows side. My primary goal in developing OnScreen DNA was to provide students (and all persons interested in DNA) with a way to reach a deeper, more intuitive understanding of DNA structure than I felt they were likely to obtain from reading text and looking at two-dimensional static images of a DNA model. I wanted to create a virtual, three-dimensional model that had most of the virtues of a real, physical one plus the enhanced power to simulate DNA processes with animations.

OnScreen DNA Lite’s computer model, programmed with three-dimensional perspective, is of the simple ball-and-stick type, in which the balls represent molecules, and the sticks represent the chemical bonds between these constituent molecules. A guiding principle in development was to make the relative dimensions of the model agree with those of the actual DNA molecule to the degree that makes sense for a ball and stick model. This meant getting the ratio between helical radius and the distance along the helix required for the molecular chain to make a complete revolution right, as well as showing the proper offset between molecules paired oppositely with one another in the two DNA strands. The distance between molecules in a strand, and hence the number of molecules in a complete revolution of the helical strand also had to be right.

Another crucial structural detail of the virtual helices that needed to conform with that of natural DNA was the handedness. The concept of handedness, which refers to the sense in which each helical strand winds around its axis, is one that seems largely to have escaped notice by those who make artistic renditions of DNA. My observation is that roughly half (the fraction predicted by a random guess) of all depictions of DNA show left-handed DNA, when in fact natural DNA (or all but a tiny fraction of it) in living cells is right-handed. OnScreen DNA Lite makes it easy to see the difference between right and left handed DNA by allowing the user to switch back and forth between the two.

In addition to showing the relative positions of constituent molecules in the DNA strands, the OnScreen DNA model uses color coding to identify the various molecular parts and chemical bonds. This is meant to give visual reality to the idea that a molecule of one type (color) will make a cross-strand bond with only one other type (a different color). The molecules that form a connection between their respective strands are represented by one another’s complementary colors. The color also makes the visual point that the molecules (nucleotides) making up the DNA chains differ from one another only in the parts (nitrogenous bases) that make up the cross-strand pairs, while the connections that form the individual strands are between molecular components that are identical. This can all be said, of course, and should be said, but the colors in the model make the point in an immediately memorable way.

The molecules (sugar phosphates) that link together to form the chain of a strand do so in a particular way. Think of elephants forming a line by each elephant (except for the lead elephant) grasping with its trunk the tail of the one in front of it. The molecules have an asymmetry (think of trunk and tail) as well, and they form bonds between dissimilar parts (the “tail” being the part of the molecule where the phosphorus atom is). Thus we can think of a strand of DNA as “pointing” in a given direction just as the line of elephants heads in a certain direction. We say the DNA strand has a certain polarity (as a bar magnet has polarity: N at one end, S at the other). It turns out that in the real world, the two DNA strands in a double helix are aligned with opposite polarity. They point in opposite directions. The color coding of the OnScreen DNA model reflects this feature as well, visually indicating it in the colors of the relevant chemical bonds.

In order to perform its biological function in living cells, the DNA molecule must at times have portions of its two strands separate from each other. The separation and unwinding of the strands, and the nucleic acid chain constructions involved in these processes are orchestrated by complex proteins called enzymes that catalyze just the right reactions at the right time and place in the required sequence. In the full OnScreen DNA edition, animated simulations are used to show how this occurs. OnScreen DNA Lite does not include these biological processes, but it does show how the laboratory process called denaturation takes place. The temperature required to achieve this is too high for a living cell to survive, but in the lab, the jiggling of the the double helix at the high temperarture is strong enough to break the bonds holding the two strings together. OnScreen DNA Lite for iPad animates this process, finally arriving at the point where the two strands are completely separated from each other and no longer have any helical shape, just as happens to real DNA in the lab under heating. The reverse process, in which bonds reform between complementary pairs to recombine the two strands into a double helix can also occur, and OnScreen DNA simulates this phenomenon of renaturation also.

Even though the biological functioning of DNA is not demonstrated by OnScreen DNA Lite, its animations can serve to make the point that the hydrogen bonds connecting the two intertwined strands to each other are much weaker than the other chemical bonds of the DNA molecule, a fact that is crucial for the strand separation that has to take place in the biological processes. Furthermore, I believe that seeing the strands in the act of recombining makes the fact of their entwinement all the more memorable, which is important because it seems it can be lost to consciousness when only two-dimensional images or the typical ladder-like double strand renderings are seen.

The desktop version of OnScreen DNA allows the user, by means of the mouse, to rotate the model about its helical axis and about an axis perpendicular to that. Making these rotations serves to enhance comprehension of exactly how the double helix structure is put together and to fix its three-dimensional geometrical shape in the mind. Causing the on-screen rotation by dragging the mouse pointer across the screen is fun, but the pointer on the screen is at a distance from the hand directing it. I, along with almost all other developers of iPad apps, was without the benefit of an actual iPad on which to test the app I was making and thus had to use the iPad simulator that runs on the Macintosh to see what the app should look like on the real device. Thus I was deprived of the tactile part of the iPad experience, as mouse clicks and drags had to simulate their finger-on-screen counterparts. I did, however, have a chance to test on a real iPod Touch the prototype of OnScreen DNA Lite for iPhone, and I loved how I could make the double helix rotate by moving my finger on the screen. It was much closer to dealing directly with a physical object, and much more satisfying. I can’t wait to get my iPad and to start making further improvements to OnScreen DNA Lite for iPad.

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More Google Follies

March 18th, 2010

Now and then I like to share with my vast readership some of the amusing Google search strings that have led people to this blog, as well as some of the mysterious or gratifying ones. Previous posts in this line are “What Brings You Here?,” “More Searchers Arriving at a Place They Never Imagined,” and “Some Google Search Examples to Start Off July.”

The search string that told me that it was definitely time to compile this post was one that brought someone to this site today, which coincidentally is the day after St. Patrick’s Day. This classic search string was “real pitcher of a leprechaun.” Now the use of “pitcher” in place of “picture” brings so many people here (where posts about Little League and the OnScreen Pitch Count iPhone app are plentiful) that I’m starting to think of “pitcher” as a candidate for alternative spelling. It is actually the way many people around where I live pronounce “picture,” which has confused me more than once when the topic was Little League team photos. But what about the leprechaun? Well, that word was used to describe a person in “A Rocky Little League Start,” which naturally enough also included the word “pitcher.” I have to assume that the person that handed that search string to Google believes in leprechauns, or at least thinks there just might be an actual photo of one on the internet somewhere. So far I’ve resisted the temptation to see what might turn up with the proper spelling of “picture.”

My post “Last Days of Chestnut, Guinea Pig” seems to bring at least one reader to this blog every day. Most of these, as I’ve noted before, are evidently people searching for veterinary or pet euthanasia advice. The desperation of these googlers comes through in the way they phrase their searches, not just in key words, but as questions or plaintive statements about their pet’s symptoms. These are often sad, as in “my guinea pig is whimpering like a baby.” An exception was one I found funny, as it was obviously the coincidence of our guinea pig’s name that brought the searcher here: “are guinea pigs allowed chestnuts.” Note that this search string is expressed as a question, which follows the letter to an advice column format so often adopted by google users, at least those with pet concerns.

I’m almost sure I’ve run across “my cat cries when we fight” twice as a search string that pointed to this blog, presumably to “Cries in the Night.” I think it’s fascinating that someone would just hand that fact (based on experience, I assume) over to google for an internet search. Perhaps they were trying to locate a first-person account they had read in the past but couldn’t remember where. I imagine they were searching for others with similarly sensitive cats though. If so, this blog would have disappointed them. Yet they came here, so perhaps something else piqued their curiosity.

I don’t have a clue how a search with “bugs bunny pulverizing pitch” led someone here, unless “pitch” alone sufficed. But that must have been on page 100 or later of the finds, after many “bugs bunny” matches. Maybe I have a reference to programming bugs somewhere.

As a more detailed example of how mere word occurrence can lead to google matches I’ll cite the google search for “bible significance of crow.” which turned up

On-Screen Scientist » Jim Crow
Jan 19, 2009 … Posts Tagged ‘Jim Crow’ … but it is also completely beside the point as regards the significance of Obama’s election. …. Yet Barack Obama is about to be sworn in as President with his hand on the Lincoln Bible. …

Yep, “Thoughts of Water on the Eve of Obama’s Inauguration” does contain the words “crow,” “significance,” and “Bible.” Nothing about Biblical significance of the crow though.

That same Obama inauguration post was evidently matched to a search on “effects of thoughts on water,” the meaning of which is puzzling, but could be about some imagined telekinetic effect I guess.

I have written (“Ronnie Knox, Marcel Proust, and I” and “Ronnie Knox, Rest in Peace“) about a certain Harvey Knox, stepfather of Ronnie Knox, the gifted quarterback who led a strange and fascinating life, but I have no knowledge whatsoever of “The Harvey Knox Pig Figurine Collection.” Sorry.

In the gratifying search category I’ll put “onscreen scienstist japense surrender,” since it leads me to believe that my post “August 6, 1945: Just Another Day in the War?” stuck in someone’s mind along with this blog’s title, even though the searcher is an even worse typist than I am.

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OnScreen Pitch Count 1.3 Is Now on the iTunes App Store

March 13th, 2010

A new version of OnScreen Pitch Count (1.3), my iPhone and iPod Touch app for recording, calculating, and reviewing pitch results and stats of baseball and softball games is now available. A major improvement to the app is the new ability to email pitch data from a game as an attached file in csv (comma-separated values) format. The csv format is one easily imported into spreadsheet programs such as Excel. Once you have the data in a spreadsheet, you can perform any of the many operations available, such as totaling the various pitch quantities for the all the pitchers in the game and so on. Also, once the data is in the spreadsheet’s rows and columns, it can be easily transferred by cut and paste to a master spreadsheet you may be maintaining with full season results, for example. The email can be sent with an attachment or with just a text summary of the results without even leaving the app. The attachment feature is one that a few OnScreen Pitch Count users had requested, so I’m glad to have it up and running.

The other major addition is the ability to record wild pitches. There is a new button to tap after a wild pitch occurs. A wild pitch is only recorded when a pitcher throws a ball beyond the catcher’s reach with the result that a base runner is able to advance; so the wild pitch (WP) button is only enabled when there is at least one base runner. This should minimize accidental wild pitch recording. This disabling of the button needs to be taken into account in a couple of instances though. When a runner reaches first base after a missed third strike due to a wild pitch, the user should first put the runner on base with the Other OB button, and then record the wild pitch. If the sole base runner scores on a wild pitch, the wild pitch needs to be recorded before the run is recorded, since that removes the sole runner from the bases and disables the WP button. This is only logical, but might not be obvious the first time. These cases are pointed out in the new pdf User’s Guide for OnScreen Pitch Count available for download online. Wild pitches are common at lower levels of youth baseball and softball, so this can be an important statistic in evaluating how a pitcher is doing and in getting to all the factors that contribute to run scoring.

The screen shots below show the new wild pitch (WP) button and the display for the number of wild pitches. It required a little shifting of buttons and labels around, but the result was good and uncrowded.

main

Above is the main screen on which pitch results are recorded by button taps.

details

Above is the screen in which cumulative game pitch totals are displayed.

A coach from Texas called me a couple of weeks ago with a question about OnScreen Pitch Count, which he was planning to use in a game that evening. I confess I was jealous. I’m sitting here in New England on a cold, rainy night, knowing baseball and softball are a month away, and with lots of cold rainouts to come even then. Not only that, when the season starts I won’t be getting a team of kids ready as I did for years in the past. It’s a nostalgic time for memories of when my kids were little. My daughter is still playing, a high school sophomore softball pitcher, and I’ll be there in the stands with OnScreen Pitch Count for all the games I can get to. It’s a good feeling to know there are others (though far from enough!) now using this app I created to capture the pitch results that I, as a coach, would have liked to have had.

You can download OnScreen Pitch Count from the iTunes app Store or find out more about it, including a video and the User’s Guide, at nondummies.com. Previous blog posts (“OnScreen Pitch Count: An iPhone App Preview”, “OnScreen Pitch Count Now On Sale on iTunes App Store!”, and “IPhone App Updates and Experiences”) say more about OnScreen Pitch Count and some of my experiences developing and presenting it.

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Free! One Week Only—OnScreen GPA Pro

February 25th, 2010

OnScreen GPA Pro for iPhone and iPod Touch, the latest app from OnScreen Science, Inc., has been available from the iTunes App Store for a little over a week. This grade-point-average calculator, with an option for multiple students, features customizable calculation formulas and an easy way to make what-if projections of GPA.

The app debuted on what turned out to be a bad day. Usually when an app first appears on the store it gets a chance to be on the first page for apps in its category ordered by release date for a day or two. There were so many apps released on the same day that, due to its assigned time of release, OnScreen GPA Pro ended up near the bottom of page 4 in the Education category from the start and then went to page 9 (virtual oblivion) the next day. It makes a lot of difference from the standpoint of initial sales to be visible on those first couple of days. Having missed that opportunity, OnScreen GPA Pro has had to rely from the start on people using the iTunes search system to come across it. A search on “GPA” brings up several apps, and, as a newcomer, OnScreen GPA Pro is not near the top of the list, not even visible unless the person chooses “Show All,” which makes it less likely people will check out its features to discover the extra power it diflucan offers.

One of the things that’s making it harder to even get that initial visibility due to a new release on the iTunes App store is that quite a few developers are releasing suites of apps all at the same time. For example, OnScreen QB Stats got swamped by a slew of apps that just followed NFL players on Twitter. There was a separate app for each team! OnScreen GPA Pro ran into a couple of foreign language series. I wish Apple would come up with a way to show a suite of apps as a single entry.

Since I last wrote about OnScreen GPA Pro, I’ve made a four-minute video to illustrate how it works. Also note that the OnScreen GPA Pro User’s Guide is online.

In order to get OnScreen GPA Pro onto more iPhones and iPod Touches and hopefully to thereby generate some good word-of-mouth (or blog) advertising, I’m making the app free for a week. Just go here and download it. If you like OnScreen GPA Pro, I hope you’ll rate it and perhaps write a brief review. If you don’t like it—and especially if you encounter a problem—please email me about it, whether or not you lasix rate it.

Tell anyone you know who might be interested in having https://www.worthingdentalcentre.co.uk/lasix-online/ an easy way of calculating GPA and having handy access to GPA records about this limited-time free download.

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A Valentine Memory: Art, Love, and Pain in the First Grade

February 14th, 2010

Since Valentine’s Day is here it seems the appropriate time to delve into my past and relate one of my first memories of that holiday, one that has stuck with me through more decades than I care to think about. St. Valentine’s Day is a quasi-holiday, not really a day on which anyone gets out of work or school, but which is still widely celebrated because it relates to ineradicable (wonderfully animal) feelings between individual human beings. It’s a very old holiday that to this day sometimes mentions its “Saint.” We learned in elementary school of St. Valentine’s celebrated love for his friends, though the holiday is much more devoted to romantic love than to the kind they were saying St. Valentine was known for. I seem to recall he wrote letters to his friends from prison, which was supposed to be the origin of Valentine cards, a tradition that figures crucially in the memory related below.

As anyone that has read any of the reminiscence posts to this blog before will have already noted, my memory is very selective, which is another way of saying it’s totally blank for most of my past. I don’t remember anything in any detail at all except events that made a strong impression at the time they happened. As it turns out, a lot of those memories are painful ones. Since a good portion of the others are of the sort I’m not going to write about, readers may obtain a false picture of my satisfaction with the life I’ve had, but that’s not something I’ll worry about.

The Valentine memory I’m about to relate is a painful one, but I wouldn’t want to give the impression that all my early Valentine associations are bad ones. My father would always get a red, heart-shaped box of chocolates for my little sister and me to give our mother on Valentine’s Day when we were little. The special shape of the box and the pleasure of giving it and then of sharing in the eating of the candy, each individual piece a new mystery to be solved by taste and sight after we’d bitten into it, made this family ritual one whose memory I cherish enough to have renewed the tradition with my current family.

When I started to write this piece I had no doubt the memory in question was from my first year of school. Then, as I began to dig the details out, I started to wonder if it hadn’t actually been a memory from the second grade. I went back and forth on the year, using clues of the details to try and nail it down. In the end I realized that process was not only futile but foolish. Why try to determine the year by clues and reasoning when I really had no doubt that over the years my memory had always placed the event in the first grade? Trust the earliest record.

There was never any doubt about which girl was the central figure in the story. It was Carol. One of the things that characterized the nascent social life of those first years of school was that the concept of “claiming” a girl was presented to a boy (and that of claiming a boy to a girl). “Who do you claim?” was a question of great interest. There was not in fact anything at all proprietary in these claims, as it required no acknowledgement or even knowledge by the person being claimed, and any number of boys could claim the same girl without antagonism. Actually, most boys did claim the same girl. In the first grade that girl was Carol. It seemed obvious that only one boy—Philip—had actually won her heart, and Philip is one of the few people that I must admit to having envied in my life. I always kept secret from everyone, even friends, the name of the one I claimed, I suppose from not wanting to be seen as one entertaining false hopes, though uncertainty as to what might be required of me should the girl I claimed claim me back may have played a role.

Carol lived near the municipal swimming pool. I think her father was the pool caretaker or something. I can halfway picture her house up on the hilltop across the road from the pool. I vaguely remember attending a birthday party there once. Naturally, Carol could swim like a fish. That fact and her being so completely comfortable at and in the pool, which I liked to go to, but could not yet actually swim in, was somewhat intimidating. I wouldn’t be surprised to hear she was athletic in her high school years, but my family moved away in the fifth grade, so I have no knowledge of her after that. I really have no memory of her after the second grade, now that I think of it, which just means she doesn’t figure in any more intense memories. I don’t believe I was ever completely comfortable with Carol, who was more mature and self-assured than I. Though I was never one to make public whom I claimed, I secretly joined with the majority in asserting my wishful title to Carol.

The question of what “claiming” a girl meant to me is not an easy one to answer now. I can’t remember having had a strong crush on Carol really, and I had experienced that phenomenon at an even earlier age. It’s just that somehow my embryonic yearning for the female of the species had become focused on her. This was, from the standpoint of my consciousness, a presexual phase of my life, in that I had no inkling of even the existence of copulation as a phenomenon of human or animal existence. I knew girls liked boys and vice versa (no other possibilities were mentioned) and that there was some silliness involved in their pairings, and that they kissed and of course got married. I even knew that my friends and I were fascinated by pictures of pretty women without much clothes on, but I had no idea why. All this is worth a lot more contemplation, but now I just want to make the point that, while it was a time of innocence, yet I felt a sort of attraction to members of the opposite sex of my own age and was susceptible to their charms. In addition to this attraction there was a prestige that went with being liked by the prettier, higher status girls. And at the top of that list in the first grade was Carol.

While I was still trying to decide on the year in which this story took place, one of the strongest arguments in favor of the first grade was that I didn’t think my mother would have been able to make me do what I’m about to relate by the second grade. Since I was in the minority that hadn’t gone to kindergarten, which was not mandatory then, I had not been assimilated into the general culture of my small Texas town’s children before I started first grade. I had to contend with being slightly different from and uncomfortable with the other kids. In some ways my mother made it harder. She had her own ideas about what a first grade boy should wear, for example. I was one of only two boys (the other being the son of one of my mother’s friends) sent to school wearing shorts and sandals. It was hot in the fall in Texas, so this was a reasonable choice from the standpoint of the weather. And no doubt I was “cute” wearing them. The problem was that every other boy except for Billy (I was so grateful there was one other!) was wearing blue jeans and tennis shoes (as we called sneakers in those days, assuming anyone still knows what sneakers are). I felt intense discomfort from this deviation in my attire from the standard and was eventually able to get my mother to buy the regulation outfit, to my great relief.

Unfortunately, as my first grade Valentine’s Day approached, my mother had an idea which my strong and prolonged resistance proved unable to overcome. She had somehow arrived at the notion that I should make every girl in the class (not to hurt any of their feelings for having been left out, always one of her prime concerns) a Valentine card. I mean literally a hand-made Valentine card, a heart cut out of red construction paper and with a lace border. That was bad already. Very bad. Hand-made was bad. Heart was bad. Just for the girls was bad. A hand-made heart to each and every one of the girls was very bad. The final detail that made the proposal insufferable was that each card was to bear the hand-printed message “I love you.” I don’t know how my mother could have been so out of touch with the reality of first grade life as to think that was something for a boy to do. The charm of the idea was so great for her that she would not yield to my objections, and I, a six-year-old, had to accept this unfortunate whim of hers.

How I dreaded that day when Valentine cards would be distributed in class! All of the cards other children were giving were of the five-and-dime store humorous sort: silly puns like “bee mine” with a bee pictured. I’m almost sure I only had cards for the girls. It’s my duty to say that a big part of my reluctance to giving such cards was my dread of the ridicule and teasing I might receive from having given “I love you” cards to the least esteemed of the girls. Anyway, there was that fear of ridicule which went beyond the already strong desire not to be the odd, possibly sissy, boy with the hand-made cards for the girls. I dreaded hearing one of the boys say to the class “Hey look! Bobby gave a card with ‘I love you’ on it to Thelma!” (Not a real name.)

The fateful day of our class Valentine party arrived. Full of dread, I dutifully took my cards to school and handed them over for distribution when the time came. Did I actually meet with ridicule for my cards? I can’t remember anything distinctly about it, which probably means I didn’t encounter much, and none from a class opinion leader. But there is a very strong memory associated with the cards which has flooded other details, leaving them submerged under murky water.

The absurd thing about this Valentine card episode is that, despite my struggle against having to make and present these cards to the girls, at some point, possibly at the last moment, I had begun to hope that it might actually turn out to be a blessing in disguise in regard to Carol. Here was the opportunity, though one I would never have chosen, to show off my artistic talent to Carol through my card. Certainly hers was the one I had truly taken care with, while striving to make it beautiful. Surely hers was the one for which the words in some sense spoke truth. I had no doubt that the card was beautiful. How could Carol not be struck by that beauty? What a thrill it would be if she looked over at me and smiled with pleasure after admiring my card! I could picture her complimenting me on it as she thanked me for having created it. Perhaps my card would so impress her that its message of love would be met with favor. Perhaps she would even start to “claim” me. What a boost it would be to my status in the class when her new fondness for me became known!

I watched intently as Carol went through the pile of Valentine cards on her desk, casually examining each one. Anxiety, anticipation, and hope mounted in me as she came to mine—and instantly tossed it aside! Discarded my masterpiece with scarcely a glance! It was hand made. It was ugly and unworthy of a second’s contemplation. It had a contemptible message from an insignificant boy.

I don’t know how far away I was from the scene of my secret rejection or whether Carol had been aware that I was watching. There was no look my way. I’m sure she never gave it a second thought or had any idea of the pain her indifference had caused. But to me it was a rejection, and nothing is worse for a man’s ego than being rejected by a woman, even when the “man” and “woman” in question are only six years old. Nothing had really changed, but, in the split second it took to dash my unwarranted hopes, the acid of disappointment became so concentrated that it etched the memory deeply in my mind.

The memory of Carol’s indifference to my art work and its message of love is still painful, much as my baseball misadventure related in Show Me Where It Hurts is painful; but it’s pretty much the nature of my lasting memories that, as the song goes: “If it wasn’t for bad luck, I wouldn’t have no luck at all.” So I’m grateful for this memory that is strong enough to place me back in my first-grade classroom, once more that six-year-old boy full of watchful hope—even unreasonable hope that I know now is about to be demolished.

ADDENDUM: Since I wrote this I have realized that I almost certainly combined two events into one, which was the source of my uncertainty about which year I was trying to recall. See my later thoughts at A Valentine Memory Revised.

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OnScreen GPA Pro: An iPhone App Preview

February 10th, 2010

My very long absence from this blog has been due once again to work on an iPhone app, but I plan to take a break from coding, assuming the app, which I just submitted to Apple for approval today, doesn’t require quick revision. As the title of this post no doubt indicated to anyone potentially interested in the app, it is an app that calculates grade point averages, universally known as GPA among those concerned with them. My first encounter with the concept was as a college undergraduate. My high school had kept what amounted to an equivalent sort of average, the one where an A was a 95 and so on. In college, where courses might have different credit values assigned to them, a different method was needed, based on the idea that, for example, making an A in a 4 credit course and a B in a 3 credit course was a better result than if the grades for the two courses were swapped. So grade points were assigned by multiplying the worth of the grade times the credits for the course, with an A being worth 4, a B worth 3, and so on. Add the grade points up and divide by the sum of the credit values of the courses to obtain the GPA. For historical accuracy, I should state that the University of Texas in my day used a 3 point maximum (for all A’s) system, but the principle was the same.

It seems most high schools have by now adopted the GPA method of ranking students. That much I understood, but in recent years I became aware of a wrinkle that has been added to high school GPA calculation. At my kids’ high school, an honors class gets an extra half a point added to its grade, making a 4.5 the maximum grade point per credit for an honors class, while an Advanced Placement (AP) course gets a full extra point added. I suppose one motivation for this “weighting” of grades (as its called, though I’d have called it “incrementing,” since there’s not really a multiplicative factor involved) is to encourage students to take the more challenging courses without fear of bringing down their GPA. Of course it also encourages students that are competing for class ranking and to get into very competitive colleges to load up on AP courses. Given that weighting of courses seems to have become the rule, that then puts students at high schools that don’t offer AP courses at a disadvantage, which has led some colleges to look rather at “unweighted” GPA. Other college admissions offices may keep the weighting, but eliminate the non-academic classses such as gym, as they recompute the GPA.

Thus there can really be a number of GPA a high school student might be interested in knowing. A college student needn’t consider weighting, so far as I know, but a student planning to apply to graduate schools may need to be mainly concerned with grades in the major subject, possibly only the upper division courses. I know that as a physics undergraduate, I was given to believe that my GPA in upper divsion math and physics courses were what mainly mattered. It was these sorts of considerations that convinced me that a flexible GPA-calculating app that allowed the user to maintain a set of customizable formulas for doing the calculations would be worth developing, since from what I could tell there wasn’t such an app already being sold.

To obtain the flexibility I wanted, the app would need not only to do weighted and unweighted calculations, it would also have to provide an easy way to include or exclude certain courses such as non-academic ones or courses outside the major. So in addition to having standard, honors, and AP categories, I added an “other” option, just for ease in selecting whether to use a course in a given calculation. An example of a course definition is show in the app screen shot below.

course

An example of a calculation method with the choices available is shown below. The user can create just those of the four possible definitions (weighted/unweighted with others included/excluded) wanted for the GPA records. When I say four, I’m assuming the other options of grade step and A+ handling would be the same for all calculations of interest, which might conceivably not be the case.

method

If even those four aren’t enough for a particular case, I’ve made it easy to duplicate a whole year’s (or other term’s) courses. Thus there could be two versions of the Sophomore Year with some courses absent from one of them. A simple on/off switch in the list of terms makes for easy switching between the two cases. This feature of optional inclusion of a term in the GPA calculation can also be used for calculating the GPA under different future scenarios. Note the “Best Case” and “Worst Case” Junior Year options in the screen shot below.

main

An example of the courses defined for a full term is shown below.

term

I also decided to make the app capable of keeping the grade records and GPA calculation methods for multiple students. All the GPA files stored on a given iPhone or iPod Touch are available for inspection and modification through selection from a list, as shown below.

files

Finally the app description that was submitted is seen below. Details of how the app works are in the User’s Guide.

OnScreen GPA Pro provides these extra benefits:
• Gives you the power of multiple customized GPA calculation formulas to match any school’s method.
• Lets you keep grade records and calculate GPA for any number of students.
• Makes defining and calculating GPA for what-if scenarios a snap.
• Makes it easy to calculate GPA including or excluding a user-defined course category.
• Allows fractional credits.
• Simplifies entering new data by allowing duplication of existing courses, terms, and whole files.

See the OnScreen GPA Pro User Guide at http://nondummies.com/onscreengpapro.pdf to get a fuller picture of the app’s power and simplicity.

Say you’re a high school student and you’ve set up your GPA calculation to match the way your school does it. That’s what you need for determining class rank. But what if the college you’re applying to turns out to use a different method? Perhaps they don’t consider non-academic courses, such as gym. Perhaps they don’t use a GPA “weighted” to give extra grade points to honors and AP classes. With OnScreen GPA Pro, you just define a new method to match that school’s way and calculate GPA using whichever method you choose. There’s no point being limited to one or two calculation formulas, when this app lets you define one to match that of any school or to make one up to satisfy your own curiosity.

In addition to standard, honors, and AP categories for classes, there is a “wild card” category called “other”, which can be anything you choose it to be. You can define a calculation method to exclude the “other” category. For example, if you’re a college student considering graduate school, you may find that upper-division courses in your major are of greatest importance. OnScreen GPA Pro makes it a snap to calculate your GPA for just those courses. If you’re a high school student, you can peg your non-academic courses as “other” and define a calculation method that excludes them, while having another that includes them.

The app is flexible in another valuable way. You can easily include or exclude from your GPA any given terms or years you choose. In addition to making it easy to see how your GPA has changed from year to year, this gives you the power to make “what if” scenarios for the future. What if you make all A’s your senior year? Just define a best case senior year as one of your terms. Include it in your GPA calculation to see how much it can change where you currently stand. It’s as simple as tapping an on/off switch on your iPhone screen. Use this as a motivational tool.

If you really are a “GPA pro,” i.e., someone whose job involves accessing a lot of GPA, such as a high school guidance counselor or college admissions interviewer, then OnScreen GPA Pro’s ability to keep complete grade records with GPA for any number of students on your iPhone or iPod Touch is obviously a feature you can use. But even if you’re not a pro, you may appreciate the ability to record the grades for all of your children or for friends and siblings. The other benefit of having multiple files is that you can make a backup file, just in case you accidentally delete something from your record.

To make entering new terms and courses faster, OnScreen GPA Pro lets you duplicate ones you’ve already created. It’s faster to duplicate your whole junior year with the name senior year, then go through and edit the course names and grades than to create a new term called senior year and add courses to it one by one. But you can do it either way. Duplicate your whole file to make a backup or to use as a template for making a file for a friend with a similar schedule.

Taken together, the features outlined above put OnScreen GPA Pro in a class by itself.

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OnScreen QB Stats: A New iPhone App for Evaluating Quarterbacks During and After a Game

December 30th, 2009

OK, having spent several weeks working on OnScreen QB Stats™, a sports-category iPhone app that just made it to the iTunes App Store about a week ago, I want to say something about it and how it came to be. As its name will probably imply to most readers, the app concerns American football (I’d forgotten the field has a different length in Canada, so Canadian football must wait), specifically the player that is most important on most teams, the quarterback (QB). He’s the player that handles the ball on virtually every play and has the biggest chance of deciding who wins the game through his ability to move the ball down the field in big jumps by completing passes, including some that score touchdowns. Of course the quarterback can also squander a down by throwing a pass that can’t be caught or, much worse, he can give the ball to the other team by throwing a pass that’s intercepted. Naturally people would like to quantify quarterback performance, so, in addition to being a very important player, the quarterback is the player for which there are the most statistics recorded and calculated. OnScreen QB Stats enables one to record a quarterback’s raw passing results during the course of a game and review the derived stats such as completion percentage as well. It can be used to record and display on an iPhone or iPod Touch the passing stats of every quarterback in the game for each team.

The full set of quarterback statistics recorded and calculated by OnScreen QB Stats is shown below.

details
The User’s Guide for OnScreen QB Stats is available as a pdf file. There every button and display is briefly explained.

After finishing my first app, OnScreen Pitch Count™, I had begun to think about making a version for the iPhone of OnScreen DNA (my virtual model of the double helix molecule of life, which runs on Macs and Windows PCs). I had already started experimenting with OpenGL ES toward that end, when it occurred to me that a lot of the nitty gritty coding I’d already done for OnScreen Pitch Count, which allows a user to record and review the results of baseball pitchers’ pitches, could be easily adapted to an app that followed quarterbacks’ passing results. That is, the machinery for saving and restoring the passing results, for reviewing those results, and for setting up the data storage for the results of individual quarterbacks on the two opposing teams, would be but a minor change from that already developed for the pitchers in OnScreen Pitch Count. That actually turned out to be pretty true. One modification was that I had to allow for the possibility that a quarterback might re-enter the game after being replaced for a time, which is not something that happens in baseball.

I had also assumed that the actual data entry by tapping buttons on the screen would be at least as simple for the pass results as for the pitch results. I thought the bookkeeping involved would be simpler for football, since I wouldn’t have to worry about strikeouts, walks, outs, base runners, and innings (not to mention complications such as charging runs to pitchers after they’d left the game). I thought I’d be able to write the football app in three weeks or so, finishing it in time to justify working on it for the current season. Since every high school, peewee, and non-bowl college game in the country (as far as I know) had been played before the app finally became available, I obviously misjudged the complexity of the task. All in all, when I consider things like the extra choices that had to be coded for undoing an action (e.g. completely wipe out a touchdown pass, call it incomplete, or place the ball short of the goal line), and the numerous states to which the app might need to be restored after an interruption (e.g. awaiting line of scimmage determination after a pass completion) the quarterback app seems to have been more work than the pitching app.

There is less to record for a quarterback than for a pitcher. We need to record attempted passes, completed ones, and intercepted ones. Then we need to keep track of the yards gained passing and the number of touchdown passes. Those are the basics. I added quarterback sacks and longest completed pass for good measure, but from the basic pass statistics we can calculate derived quantities such as yards gained per passing attempt and the rather arcane numbers called quarterback rating in the NFL and passing efficiency in the NCAA. Both of these rating methods use pass completion percentage, yards per attempt, interceptions, and touchdown passes to come up with a number that serves as a basis for comparison among quarterbacks. Although, the number is much less meaningful in a single game than in a season, it can be of interest to know what it is for a game, and OnScreen QB Stats will calculate and display whichever measure of quarterback performance the user desires.

Although the data to be recorded might seem at first glance to be simple, in practice it is more complicated. Someone sitting in a press box with a spotter to provide the details of each play could get by with an app that recorded completions, incompletions, yards gained, interceptions, and touchdowns. But for someone watching a game from the sidelines or stands or even on television, there is the problem of determining how many yards were gained on a given play. The only way to do that with full confidence is to keep track of where the ball is after each play, since one doesn’t know in advance which plays are going to be passes. Once a play is underway, it is difficult to note the line of scrimmage from which play started and then calculate yards gained by noting where the receiver was brought down. It’s a lot to take in and keep straight in a short time, even assuming one has a good view of the sideline yard markers, which is often not the case when watching a game on television. The additional challenge is to do all the data entry on the iPhone without recourse to pencil and paper or on-the-spot mental calculations.

OnScreen QB Stats solves the problem of passing yardage calculation by making it easy to record the new line of scrimmage after each play; and if the play leading to the change of field position is a completed pass, the app automatically calculates the corresponding gain in yards and adds it to the total for the game, while adjusting all other stats that depend on passing yardage as well.

It took me a lot of trial and error to come to this easy way of recording the new line of scrimmage after each play (or penalty). At one point I had thought that using a slider control to just slide a pointer along a representation of the 100 yards of the field to mark the current line of scrimmage would be both intuitive and fast. I ran into two problems with the slider method. For one thing it was hard to quickly obtain the precision I needed down to the yard, which is only 1% of the length of the control. So, I added a second fine-tuning slide control to move the pointer just within plus or minus a couple of yards of where the full-field control pointed. This solution worked, but frequently required using both controls, which was a nuisance. I might have decided to live with it, given the intuitiveness of the slider, but the controls turned out not to be reliably responsive on an actual device. Sometimes the sliders were easy to drag, sometimes they seemed in need of a squirt of WD-40. It was hard to ditch all the work that I had put into that method of yard line setting, but I decided I had no choice but to code a new method.

The solution I came up with can be seen below.
yardset
The screen above shows how one enters the new line of scrimmage after a play has been completed. This screen appears whenever the user taps a button to record a play from scrimmage or a penalty (or simple need to adjust the current setting for the line of scrimmage). In the example shown the team with the ball has reached its opponent’s eleven yard line. Note that the “Defense’s End” is highlighted in the top control to indicate which end of the field the ball is in. That control also adjusts so that the ends of the field in the sense of right and left correspond to what the user sees, assuming the initial setup has been made correctly and the correct quarter has been maintained. Whenever the ball goes to the other team (currently called Defense), the labeling of the top control reverses (Offense becomes Defense and vice versa), so that the field situation is correctly mirrored. At the end of the first quarter, for example, the same switch takes place.

The yard marker for the current line of scrimmage is shown to be 11, and that choice has been made by tapping the tens place control (blank to 5) on its “1” and the ones place control (0 to 9) also on its “1”. There is no keyboard to deal with, and for short yardage plays only the ones place control needs to be adjusted in many cases.

The number 24 beside the “Check Gain” button shows that the user has tapped that button in order to see how many yards will be recorded as having been gained, assuming the ball is marked at the 11 yard line. The previous line of scrimmage must have been the opposing team’s 35. The “Record Pass” button is to be tapped once the user is satisfied with the choice of yard line (here the 11) and need not be tapped until the final spot has been made to minimize the need for adjustments. The button’s title being “Record Pass” indicates that the play just over was a completed pass. On a running play (or pass by someone other than the quarterback), it would be reading “Record Gain” (or “Record Loss”). The “Touchdown” button’s use is obvious, and in the case of a touchdown pass, there is no need to set the yard line button by hand.

The screen below shows the most basic results of the quarterback’s passes and also contains the buttons for registering which type of play has occurred. The pass results shouldn’t need description. The four buttons stacked in the lower right are for recording pass results or for canceling out the previously recorded play (“Undo”). We are especially interested in eliminating the chance for accidental recording by unconscious taps for these four buttons, so they all require a double tap to work. Double-tapping the “Incomp” button just increments the number of passes and the Down, which is displayed in the yellow area along with the yards needed to make a first down and the current location of the ball, which is the opponent’s 42-yard-line. The display of the “42” in red indicates the team with the ball has crossed midfield into the other team’s territory.
basics
The down and yard marker are kept up to date by the app as a way of providng a check on whether the user has entered any data incorrectly. For example, if the user had failed to register that the team had crossed midfield, and had chosen the 42 yard line in the quarterback’s team’s end of the field, the display would be in black instead of red. As a further means of insuring ball movement is recorded in the proper direction, the user has two buttons to choose between for plays from scrimmage other than quarterback passes—”Other Loss” and “Other Gain”. If a gain has been chosen, then the new line of scrimmage must be in the right direction for a gain. The other buttons are to be used for what you’d expect given their titles. Kicks and turnovers lead to the other team having the ball, as do touchdowns. The “Go on Def.” button also gives the other team the ball, but shouldn’t be used except to correct a user mistake or when there’s been a fumble lost after a turnover of some kind not on a play from scrimmage (e.g. fumble lost on punt return).

Using OnScreen QB Stats just amounts to keeping track of the line of scrimmage and recording pass results. The app does all the calculations, including yards gained on passes. Recording pass results for a game on television can be challenging because so few announcers now state where the ball is after every play (I’d guess less than 25%). The line of scrimmage is often not shown until right before the snap, and it can often be difficult to see where a runner was tackled due to the camera angle when the tackle occurred (followed by the three replays with no view of the sideline markers). Even a televised game can be followed smoothly, though, after a little practice.

I think I can safely say that as of now there is not another app that allows one to record all of these passing results and view these stats for quarterbacks during the course of a game. So I’m hoping word gets out to those crazy folks (like me) that might like to have that power. If you know one, pass the word. It’s on the iTunes App Store here.

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IPhone App Updates and Experiences

December 22nd, 2009

The biggest news on the app front is that OnScreen Science’s second iPhone app, OnScreen QB Stats, an app for recording, calculating, and reviewing the passing statistics of quarterbacks during and after football games, is now available on the iTunes App Store. I’ll devote another post to that soon, maybe tomorrow, but I want to catch up here on app number one, OnScreen Pitch Count.

OnScreen Pitch Count went on sale from the iTunes Apps Store August 26. I won’t go into the details of the typo I had in the press release I sent out or dwell on how the video I posted to show the app in action worked fine on a Mac or Windows PC, but not an iPhone. That’s all in the distant past, fixed and forgotten.

Once the app had made it to the iTunes App Store, I was looking to find reviewers for it to help get the word out. I’d had magazine reviews of my science education software in the past, all of them quite favorable (a four-star Macworld review of OnScreen Particle Physics caused a major uptick in sales years ago), but not in a long time and never, of course, for an iPhone app. My number one hope was that the Macworld web site would post a review. As luck would have it, Macworld had not long ago reviewed another pitch count app. That showed they had someone sufficiently interested and knowledgeable to do a review, but it might also make it less likely they’d want to devote space to another example in this little niche, even one that was better than the first, especially so late in the baseball season.

Apple provides every developer of an app forty “promo codes” for the free downloading of each new app or update. I sent a promo code with a review request to the email address of the Macworld reviewer, but never got so much as an acknowledgement. I hadn’t counted on a Macworld review anyway and had found other iPhone review sites (a good number of which are devoted solely to games) and approached a few of them. One or two review sites responded with the suggestion that I expedite a review by paying them. That I wasn’t about to do, and I wouldn’t really trust their reviews after knowing how they operate. A couple of reviewers took the trouble to download the app, test it thoroughly, and write a review of it, for which I am grateful.

The two iPhone app review sites that reviewed OnScreen Pitch Count were AppGirlReviews and JustAnotherMobileMonday (JAMM). I ran across the AppGirl on Twitter, and she was happy to take on the review (actually to pass it on to someone on her staff). I learned of the JAMM site via Google. JAMM had reviewed iScore, a baseball scorebook app, for the iPhone. This review showed the reviewer to be a baseball fan who liked to keep score during a game, which I thought, correctly as it turned out, made him a good candidate to review OnScreen Pitch Count.

Even though I felt the app was solid, and it had passed Apple’s review, I still felt some anxiety over the possibility, however unlikely, that a reviewer would uncover a crashing or data-scrambling bug. On that score I was quite relieved, as both reviewers had nothing but good experiences to report. There was plenty of agreement on the performance and power of the app and its ease of use, really, despite complaints about interface. The JAMM reviewer in particular disliked its looks, and I can’t blame him. I had used Apple’s Interface Builder’s oddly minimalist, totally two-dimensional rounded-rect default buttons for the interface.

My hope was that someone wanting to track a kid’s pitches wouldn’t be totally repelled by the looks, and I didn’t want to delay the app’s launch any more than I had to. Of course an unappealing interface can indicate overall lack of care, which by assumption might carry over to the actual functioning of the app. Fortunately, the reviewers used the app enough to see how well it worked. The JAMM reviewer couldn’t stand the app’s looks, but acknowledged that “like the story of the Ugly Duckling, there really is a fantastic and robust app hidden inside there.” In addition to general aesthetic objections, he wanted a more graphical interface (instead of labeled buttons presumably), but I confess I don’t know how to come up with something that would convey “ball” as well as the word. And so on. A great deal of experimentation went into button placement in fact during development.

For opposite reasons, which is interesting, both reviewers emphasized the limited market for OnScreen Pitch Count. The (male) AppGirl reviewer, in particular, seemed downright offended that I suggested in the app’s description that a normal fan might enjoy tracking pitches in a game he or she was watching. My claim was based on my own experience in testing the app, but the reviewer really took exception to the idea, noting that nonetheless he would let it pass and only report on how the app functioned. That is basically what he did, and he had plenty of good things to say, recommending it without qualification for coaches and parents of pitchers. But in closing he came back to say that otherwise it was of interest only to “fanatics,” and that it was “burdensome” to record pitch results. Despite all the positive things he’d said in the middle of the review (the only serious complaint was lack of email capability, which he thought was a “glaring” defect), he gave the app a mediocre numerical score.

The JAMM reviewer, on the other hand, felt the app would be of limited interest because a regular (not a fanatical) baseball fan wants to record much more than pitching data, as in a full scoring of batting and baserunning results. Clearly there is a wide range of fan interest in keeping personal track of what’s happening in a baseball game, from nothing to everything. I still think there are some that may want pitching stats in particular, since pitching is so important, especially when it comes to managers’ decisions.

I was so happy that both reviewers (real world people I’d never met) had found the app to work perfectly and to be of great potential use to its primary audience that I didn’t let any negative comments bother me. Really.

A little after the reviews appeared someone posted a user review on the iTunes App Store, which gave OnScreen Pitch Count five stars, but also mentioned the need for email. My first update would add email. This update (version 1.1) was approved and posted for sale on the iTunes App Store on September 17. After the update had been posted, I noticed the iTunes summary said that iPhone OS 3 was required for my app. Since I had gone to quite a bit of work (following Apple’s guidelines faithfully) to use the improved emailing capability of version 3, while providing downward compatibility with OS 2.2 (through use of weak binding and conditional execution, for the cognoscenti), I was not happy about this. My query to Apple was unanswered. I decided to live with it and move on to requiring OS 3 or greater for future updates. This affects iPhone customers almost not at all, but about half the iPod Touch users have yet to upgrade the OS, since they have to pay to do so. I recently discovered an iPhone developer discussion thread about this very problem of OS-requirement change as being due to an Apple bug.

Another user rating led to version 1.2. This user expressed the desire to see pitch results expressed in percentage form as well as total numbers. The update incorporating this new feature was posted for sale October 15. Finally, I addressed the ugliness issue and made the minimal, but significant, change to the use of better-looking buttons. The new buttons, while not photo-realistic, are pleasing I think, looking a bit like they’ve been rendered by colored pencil shading. Version 1.2.1 with the new look was approved as I wrote this.
basic
basic

UPDATE: See also “OnScreen Pitch Count 1.3 Is Now on the iTunes App Store”.

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Belichick Is Not a Gambler: He Played the Percentages Last Night

November 16th, 2009

What got into Bill Belichick, coach of the New England Patriots, last night to make him suddenly become a reckless gambler? That’s the question stunned New England Patriots fans have been asking themselves after he seemed to throw caution to the winds by deciding to go for a first down rather than punting in a key situation last night. The Patriots had the ball on their own 28 yard line in a fourth and two situation with about two minutes to play and a six-point lead in their game against the Indianapolis Colts. The Patriots went down to a crushing defeat when they failed to make the first and the Colts then scored 7 points to win 35-34. Naturally, Dan Shaughessy of the Boston Globe was pulling out all stops to express the monumental stupidity of the coach’s decision, saved from eternal ignominy (perhaps) only by its not having been made in a post season game.

I was as surprised as anyone when I saw the Patriots were going for the first down, but on further review, I am going to argue that Belichick made the right call. The timing of the call is crucial because the first down will be decisive if made. With lots of time to play, of course you punt. And for a random game picked out of a hat, this situation would seem to require a punt without a second thought. Get the ball away from your goal line and play prevent defense. What are the odds the other team can move 75 yards in two minutes in a high pressure situation? What are the odds you’re going to pick up two yards against a team geared to stop a short gain?

But this was not a random game between random teams. First of all, the two best quarterbacks in football were playing in it, and that has a strong bearing on the likely outcomes of different scenarios in the last two minutes of a game. One has to consider all the specific personnel of the teams and their current state of exhaustion, the crowd factor, and that real psychological edge people called “momentum.” No, this is not a question that has a universal answer, though Belichick may be one of the few coaches who would realize that.

In addition to Brady, the Patriots have other veterans of Super Bowl Championship teams, including the invaluable Kevin Faulk. These are players that actually get better in pressure situations. The starting point in a decision has to be what are the odds that Tom Brady will be able to complete a two yard pass to Kevin Faulk on third and two from the Patriots’ thirty? From what I’ve seen of these two clutch performers, I’d say about 80%. I’m sure Belichick has a better estimate. What if it’s fourth and two? The odds could go up a little because the Colts have to be thinking that the whole thing may be just a ruse to draw them offside. The Colts must be holding back until they are sure of the snap, thus giving Brady a fraction of second more time to make a decision and an unhurried throw. On the other hand, they aren’t going to be worried about deep coverage. Lets say the odds are that the Pats make the first down 75% of the time.

If they make the first down, the victory is basically cinched, game over. Thus the pass play gives the Pats a 75% chance of winning the game. True, if they don’t make it, based on the way the Colts have been moving the ball, the odds are great that they will lose the game. But of course that is not the comparison to make at this stage of the game with only two minutes to go. The chance of winning if the Pats go for the first down has to be compared with the chance of their winning if they give the ball back to the Colts, at say (best case scenario of negligible runback) the Colts’ 25 yard line. But what had just happened? The Colts had taken the ball 79 yards in 1:44. Manning had been sharp as could be. That means as sharp as anyone could be. The receivers had been sure-handed and were getting open. The Patriot pass rushers seemed tired. The game is in Indianapolis.

The decision formula is simple. Let the probability of making the first down be F, and the probability of a Colt touchdown after a punt be T. Then if F > (1-T), the Patriots should go for the first down. What were the odds that Peyton Manning would be able to get a touchdown in 2 minutes with 3 timeouts and the 2 minute warning to play with? Were the odds of a Colt touchdown greater than 25%? That’s the calculation Belichick had to make on the spot in a short time. If the answer to that question is a definite yes, then the Patriots should go for the first down.

One may argue about the chances of success with Brady throwing to Faulk to pick up a 2 yard first down. I think 75% is a reasonable number. I also think that the odds of Manning getting the Colts into the end zone after a punt were over 50%, which means Belichick’s decision, far from being crazy, was in fact the reasonable one. The main point is that the odds to compare are the odds of the Patriots making the first down and thus assuring the victory versus the odds of Colts scoring after a punt (not after getting the ball on downs). The decision formula F > (1-T) would still say go for the first down even if the chance of success was 60%, so long as the chance of the Colts scoring after a punt was greater than 40%.

Did Brady choke and overthrow Faulk? No, the pass was perfect. Did Faulk drop the ball even when hit? No, but he did take a split second to gain full possession of it after being hit right at the first down spot. Just enough to make the spot short of the first down marker. The Colts defense did just enough to get the ball back. But it was a close as could be, and the call could have gone the other way. Home field advantage may have helped there. The fact that it was so close just points out to me how likely success was.

Would I as coach have gone for the first down? No, like all normal human beings I would have punted and hoped. I wouldn’t have thought to make the proper analysis in the excitement of the game in the first place, and I wouldn’t have had the guts to go against what first glance intuition said if I had. But I now see that Belichick was both smart and courageous. It’s not as though he didn’t know the consequences of failure. He wanted to win more than he feared what the media and fans would say if he didn’t. Yep, the guy is one of a kind.

This is my first (and probably last) topical sports post, but it’s been so long since I’ve posted anything (tied up with iPhone app development again) that I thought I’d better go with something that caught my attention. Back to “normal programming” soon. Maybe.

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