2018 Texas Wrap-Up Part 1: The Top

Was 2018 the most successful year in Texas history?  Or were the high scores a symptom of inflation? Let’s look back and see if we can quantify the year that was in Texas.

 

Starting at the very top, Lubbock was the one of the highest scoring state champions in Texas history, only being beaten by the last two Highland Park championship teams.  Their balance along all three divisions with stellar representation at the top in their scholastic and varsity divisions allowed them to push to their second state championship, and first since 2002.  If you take their score and compare it to the rest of their competition this year, it would make one hard-pressed to see them as one of the top 3 state champions in Texas history. One of the better ways to see how they stack up against the rest of the year is to look at their z-score.  A z-score looks at their data point and compares the difference between that number and the average of the data set to the standard deviation of the rest of their competition; the standard deviation is how far away the average team was from the mean. Comparing Lubbock’s z-score to the standard deviation, their gap to the average score is 1.73 times greater than the standard deviation of the entire data set.  This would be the lowest z-score from a state champion team since 2003 and the second lowest since 2000 (where will be normalizing all our data to from now on).

 

Does that make Lubbock the 2nd worst state champion since 2000?  I don’t think so, and I think they are significantly better than their z-score indicates.  Most of my feeling on this comes from anecdotal evidence, however I also believe there is statistical data to prove this.  The first thing that I believe really dismisses their z-score is my own experience over the last two years as the coach at Dulles.  In 2017, we placed second to Highland Park with a z-score of 1.92. To beat that, Lubbock would have had to score around 53,800 this year- which seems pretty absurd.  Our 2017 team was great, but as a team we did not have the honors or the varsities that Lubbock had this year; I would even argue that the 2018 Dulles team was better than the 2017 team, who Lubbock beat!  So I don’t really buy this low of a number for Lubbock (unless last year’s Dulles team has a z-score that is too high).

 

So, where does this statistical weirdness come from?  I believe it is two things that combine well together to make Lubbock seem less strong than they were- test score inflation at state and a historically strong Texas in terms of depth.  The problem with statistically proving either of these is that they work hand-in-hand; are the stats proving score inflation? Or are they proving a strong year? Turns out that it is both.  What I did to analyze this is by comparing the average test score of the large school individual competitors in each subject to the past five years.

 

The most obvious point I found is comparing 2018 to 2016.  The average test score in 2016 was 40 points lower than in 2018, yet the average team score in 2016 was 990 points lower than in 2018!!  That is a gap that can’t be simply explained by better subjective performers this year, or worse ones in 2018. It could also be that 2016 had tough subjectives, but regardless that is a massive amount of subjective inflation for the large schools this year.  

Comparing the average tests score in 2018 to the past 5 years as a whole allows us to hopefully normalize some of the difference from one year where the test set was easy.  It is not the most in-depth and thorough look, but it gives us a good idea. Here is a look at the difference between the average team score for each subject in 2018 versus the average of the past five years.

 

Subject 2018 Avg of ’17-’13 Difference
Math 3976 3102 874
Music 3934 3570 364
Econ 3598 4086 -488
Science 4090 4106 -16
Literature 4724 3733 990.8
Art 3936 3856 80
Social Science 4174 3498 676
Total 28432 25951 2481

 

What we see is that despite economics being the toughest it has been in the past five years, that toughness is counteracted and then doubled down upon by literature alone.  Add in incredibly easy math and social science and this makes this one of the easiest years in terms of objectives over the past five years, and likely since 2000. Most years tend to have 1 or 2 hard tests, countered by 1 or 2 easy tests.  This year had 1 hard test countered by 4 easy tests with 2 normal tests in science and art. This makes Texas as a whole look WAY better than it may have actually been. “But what if teams were just REALLY good this year?”  That is a very likely possibility, but a difference of 991 points in literature versus the five-year average tells me that those tests are responsible for at least half of that difference, if not more. A strong year may be able to account for 100 or 200 points over an average test. If you were to subtract 2,481 points from each team’s test score, you may be able to get a better view of the state as a whole.

 

In conclusion, I think that Lubbock’s low z-score, a score that should show you how great a team truly is more than their score alone, is skewed highly in 2018 due to inflated subjectives in large school and the easiest set of tests in at least the past five years, and probably since 2000.  When tests are harder, the teams that are the best tend to be able to increase their gap on the lower teams despite losing points themselves. So, Lubbock, Dulles, and Highland Park would have statistically been shown in a better light this year than they are based on this study.

 

In the next part, I will look at the rest of the state and see if we can see any major changes in individual programs and focus on some up-and-coming schools.

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