## Calculating a GPA

Have you ever wondered how to calculate your grade point average?  If so, boy have you come to the right blog post.

Here’s what you need to do:  Take your Grade in a given course and assign it the number of Points for that grade (e.g., an A is 4 points, A- 3.75 points, B+ 3.25 points, etc).*

Once you’ve taken care of that, multiply the number of Points by the number of Earned Units for that course.  So, for example, if you earn an A in a six-unit course, your total quantity of points (Qty Points) would be 4 points for an A times 6 Earned Units = 24.

Now you can add up your total Qty Points and divide by GPA Units and, wah lah, you have your Grade Point Average.

As example, you take four courses in your first term, get a B in Freshman Studies, a B+ in Geology, and an S in Economics because you S/Ued the course, an a B in a one-unit piano performance course.  Your grade point average would only include courses with grades and would be calculated thusly:

(3 points x 6 units + 3.25 points x 6 units + 3 points x 1 unit) / 13 units = 3.12

And if you’d like an Excel spreadsheet that does it for you, here it is (email Professor Galambos with comments or questions about the spreadsheet).

* A full list of Grade Points can be found here

I was just going through some work on the economics of higher education, and I came across this remarkable piece of scholarship* estimating the effect of studying on grades.  What a concept!

Of course, one would expect (or would hope to expect) that more studying results in higher grades, but how much studying and how much better? Can studying really make up for a lack of high school preparation or a deficit of intellect? Can smart kids really skate through?

Using data from Berea College, Ralph and Todd Stinebrickner provide a very, very nice framing reference for the relationship between incremental study time and the endowment of “book smarts” (measured by ACT scores):

[H]uman capital accumulation may be far from predetermined at the time of college entrance. For example, using results from our full sample, an increase in study-effort of one hour per day…is estimated to have the same effect on grades as a 5.21 point increase in ACT scores.

So while on the one hand hitting the books is certainly a plus, danger lurks around every video console:

In addition, the reduced form effect of being assigned a roommate with a video game is estimated to have the same effect on grades as a 3.88 point decrease in ACT scores.

Ouch.

For those looking for good examples of empirical work, this is a very high-quality example.  This seems to have “Senior Experience” written all over it.

* Ralph Stinebrickner & Todd Stinebrickner, 2008. “The Causal Effect of Studying on Academic Performance,” Frontiers in Economic Analysis & Policy, Berkeley Electronic Press, vol. 8(1)

## IHRTUCFHC… or Not.

In this remarkable video, a professor at tells his students that he has used a statistical analysis and has determined rampant cheating in his class. I’m pretty sure what he did wasn’t a statistical analysis, but he did offer the offending students a chance to redeem themselves.

Jeff Ely from Northwestern offers some thought-provoking discussion:

So he is offering a deal to his students.  They can individually confess to cheating, attend a 4 hour ethics course and receive amnesty, or they can take the risk that they will not be caught.  What would you do?

1. Professor Quinn’s speech reveals that the only evidence for cheating is an anonymous tip plus a suspicious grade distribution.  Based only on this the only signal that you cheated was that your score was high. But it’s not credible to punish people just for having a high score.
2. If Professor Quinn expects his gambit to work and for cheaters to turn themselves in, then he should believe that everyone who doesn’t turn himself in is innocent.  So you should not turn yourself in.
3. The biggest fear is that someone who you collaborated with turns himself in and he is induced to rat you out.  Then as long as you are not sure who knows you were in on the scam you should turn yourself in.
4. It’s surprising that this possibility was never mentioned in Professor Quinn’s rant because without it, his threat loses much of its force.
5. The fact that he didn’t raise this possibility reveals that he is not so interested in rounding up every last cheater but simply to get a large enough number to confess.  That way he can say that a lesson was learned.  This suggests that you should confess only if you think that your confession will just push the total number of confessions over that threshold.  Unlikely (unless everyone is thinking like you.)

What would you do, indeed?

Well, as it turns out, about a third of the class (200 students) threw themselves on the mercy of the court.  The sheer magnitude propelled the story into the headlines in the first place, making Professor Quinn something of a YouTube icon.

But the plot thickens.

As it turns out, the “cheating” involved was for students to get access to a test bank and studying from that.  The folks over at techdirt (techdirt?) think this sounds kind of fishy.

But watching Quinn’s video, it became clear that in accusing his students of “cheating” he was really admitting that he wasn’t actually writing his own tests, but merely pulling questions from a testbank. That struck me as odd — and I wasn’t really sure that what the students did should count as cheating. Taking “sample tests” is a very good way to learn material, and going through a testbank is a good way to practice “sample” questions. It seemed like the bigger issue wasn’t what the students did… but what the professor did.

The question seems pertinent given that Professor Quinn claimed that he wrote his own questions (video here).

Now, my guess is that the students knew that Professor Quinn used a test bank, and so their faux innocence seems kind of ridiculous.  On the other hand, I spend a lot of time writing my own tests.  Indeed, even when I taught large sections of intro (150+), I wrote my own multiple choice questions, so I’m not so sure how much sympathy is due for Professor Quinn here. And it’s not clear whether the ground he is on is all that high.

I’m not sure what the moral of the story here is, but it certainly is a remarkable case.

## Whatever Works

The misery accompanying the U.S. recession / depression manifests itself firstly, I think, through the job market.  There seems to be an increasing perception that policymakers in Washington and at the Fed aren’t taking the unemployment situation seriously enough. Nonetheless, jobs are certainly on the minds of people who have them and, even moreso, people who don’t have them. We learned yesterday that the declining unemployment rate is actually bad news. Why? Well, in order to be counted as unemployed, a person has to be seeking employment, and consequently so-called discouraged workers, people who are no longer looking for work, do not count as unemployed.  And would-be workers are pretty darned discouraged.

This gives us a fundamental measurement problem, how can we determine how bad the employment situation really is?  One common way to tackle it has been to track the total adult population in the workforce.

As you can see, the picture isn’t a pretty one. Continue reading Whatever Works

## Lake Woebegone Goes to College

Have you ever wondered why your grade point average is so high?   Is it because you close The Mudd every night? Your raw intelligence?  Your unusually good problem-solving skills?  Your avoidance of my classes?

Or maybe it’s because it’s 2010 and Lawrence is a private university.  It seems that the average college GPA has been going up at the rate of about 0.1 per year for the past 50 years, with private schools leading the charge.  Here’s Exhibit A:

That’s from the NYT‘s Economix column.  The green series is the GPA for private schools over time, which appears to have started at about 2.3 in 1930 and increased to right around 3.3 today.  That’s right, the average student at a private college has a 3.3. GPA.   The grey dots show the data points surrounding the series, so this is no selection bias problem.  In fact, the lowest average GPA in the sample (about 2.7) is higher than virtually every single recorded data point prior to 1950.

The big question, of course, is why?  The answer to that is probably not so simple.  We have seen one of the consequences, however — students really do work less these days.  Recent scholarship documents an inverse relationship between the expected average class grade and the amount that students work.  To wit: average study time would be about 50% lower in a class in which the average expected grade was an “A” than in the same course taught by the same instructor in which students expected a “C.” In other words, students are working less and getting higher grades.

One point of interest is that science classes have traditionally graded much more harshly than the humanities.

[S]cience departments today grade on average 0.4 points lower than humanities departments, and 0.2 points lower than social science departments. Such harsher grading for the sciences appears to have existed for at least 40 years, and perhaps much longer…  Relatively lower grades in the sciences discourage American students from studying such disciplines, the authors argue.

So does that account for the dearth of American-born scientists — the fear of getting a B?

How do you suppose a maximizing professor should think about these issues?  If I want to push my students, do I have to be a tough grader? Or do I just end up with fewer students grouching about how much work I give them?

Click on the “making the grade” tag for more on grade inflation.

## Don’t try this at home

The administration at Louisiana State University removed a professor from the classroom for grading too harshly. Evidently, Professor Homberger gives tough multiple choice exams that aren’t curved, the logic being that “students must achieve mastery of the subject matter, not just achieve more mastery than the worst students in the course.”

I’m sympathetic to her.  Why give a student a decent grade if s/he doesn’t know what’s going on?

But, on the first exam she flunked 90% of the class, and enough of the students whined and moaned that the administration gave her the hook.

I’m sympathetic to the students. About the harsh grading, not the whining.

The irony is that her tough standards seemed to be having a positive effect: “[Homberger] said that her tough policy was already having an impact, and that the grades on her second test were much higher (she was removed from teaching right after she gave that exam), and that quiz scores were up sharply. Students got the message from her first test, and were working harder, she said.”

I think she might be on to something.  Incentives matter, as they say. And we’ve seen before,  students do seem to work harder when they aren’t handed high grades.

Fortunately for her, she’s tenured and probably would get a nice fat settlement if push came to shove here. Of course, if she wasn’t tenured, she might think twice before busting out the big red pen.