a closer look at the LD time skew

What follows is an analysis of particular empirical evidence for the fabled "time skew" in Lincoln-Douglas debate.



The Context
I've heard several theory shells that rely heavily on time skew arguments, all sharing the same warrants. For the uninitiated, "time skew" is the idea that in LD, the Negative has an unfair time advantage in the 1NR--7 minutes to run all sorts of attacks, disads, theory shells, meta-ethics, a prioris, interpretive dances, killer bee swarms, whatever--that the Aff simply can't respond to in the 4 minute spittlefest known as the 1AR. Compound this with the 6 minute 2NR, and the measly 3-minute 2AR in response, and the modern LDer feels significantly cramped while affirming.

Often, the "fairness" portion of the shell's standard appeals to an empirical fact: at the Tournament of Champions in LD, the Negative has won over 50% of the ballots.

This, of course, raises all sorts of questions.

* Is this a historical trend, or the result from one tournament?
* If one, what was the resolution? Would its own presumptions and associated judge biases cause the skewed results?
* If it's an identifiable trend at the TOC, what is the root cause?
* Do judges have a contrarian bias that favors the Neg? (Good luck answering this one in a mere blog post.)
* What if it's abusive tactics that actually create the problem?

These questions, of course, presume that the statistic is true. Is it?

To find out, I crunched the numbers myself, because I'm the fact-checking sort.


Methodology
I used the 2011-2013 LD results, based on the first six rounds, presuming that this would provide an even number of Aff-Neg opportunities for each individual debater, with the exception of 2011, which had 8 rounds for each. I counted each by hand, double-checked, and then ran the results through a spreadsheet. I eliminated two 2013 ballots, as they were both forfeits, one on each side, which doesn't significantly alter the results or the conclusions. Of course, I didn't count byes.


Results
Out of 772 preliminary round ballots in the past 3 years of competition, 345 went for the Aff, or 44.7%. Negs took 427 ballots, or 55.4%.

Before we declare the skew to be real, we have to account for the margin of error. For a sample of this size, at a 99% confidence interval (i.e., only 1 in 100 results could be explained by pure chance), we would expect an error margin of +/- 4.57%.

Thus, the lowest "expected value" for the Aff is 368 ballots, or 47.7% of the total, while the highest is 404, or 52.3%. Any result within this range isn't far enough away to be anything but intriguing.

But the actual total, 345, is well below the range. Even being optimistic, the Aff has won only 94% of the times they "should have" won, while, at worst, they've won only 85% of the times they "should have" won at the TOC. (Consider also that the skew would be stronger in the 2012-13 tournaments, which went 7 rounds in prelims, as roughly half of the debaters had one extra round on the Neg.)


Interpretation
The time skew is statistically significant. The numbers indicate that at the TOC, the Neg picks up at anywhere from 1 to 3 extra ballots per round.

What causes the skew, though? The simplistic answer is the seeming structural disadvantage of the 1AR, described above. But this is a bit like saying, "Honda Civics built in the mid-1990s spend more time in the shop than other similar makes from that era, and are thus defective," when an equally plausible explanation is that that Honda Civics are preferred wheels for crazy drivers who YOLO their way through life / the Interstate Highway System.

In other words, the TOC's emphasis on progressive, spread-based tactics has potentially created the skew, whereas it may not be a problem in a more traditional form of LD.

We might be on firmer ground if we compared results to NFL tournament preliminary rounds to draw firmer conclusions. (Maybe that'll be the subject of a future post.)


Takeaways
First, never uncritically accept a statistic, even one as potentially intuitive as this one.

Second, if the timeskew is inherent--or, as TOC tactics are now mainstream in many regions, will eventually become ubiquitous, which at that point may as well mean it's inherent--then I propose a solution: 6 3 7 3 5 6 2. Give the Aff an extra minute to work with in the 1AR, and turn the 2AR into a voters-only speech. I think it's elegant, workable, and fair. (I typically have a high opinion of my own ideas.) I'd love to hear of a tournament trying it, and getting enough data to draw meaningful conclusions.

Third, if you're running a theory shell using the TOC data, here's an easy citation.

ANDERSON: "In the past three years, over 55% of TOC elimination-round LD ballots went to the Neg, a statistically significant advantage."

Fourth, if you're running against a similar theory shell, and wish to debate the point, here's another easy citation.

ANDERSON: "It is possible, and even likely, that spread tactics themselves are the root cause of the skew, which may not exist in more traditional LD clashes."

Hint: don't run this if you're the one who started the ruckus by spreading.

Meanwhile, I'll be speeding down the freeway in my tricked-out Civic. Or in the shop getting it fixed.

#YOLO?