In this post, we compare the qualifying times for the 2019 and 2020 Eastern Zone Short Course Age Group Championships (EZ2019Y and EZ2020Y, respectively). This meet is the only zone-level age group championship offered for the short course. In a previous post, we found that the EZ2019Y qualifying times provide significantly more opportunity to boys at the expense of girls, and to older athletes at the expense of younger athletes. In EZ2019Y, a 15/Over athlete was expected to qualify for 6.1 times as many events as a 10/Under, while an 11-12 boy was expected to qualify for 1.6 times more events than an 11-12 girl.
For 2020, the Eastern Zone made two significant changes to their short course age group championship. Firstly, the organizers dropped the 15-18 year old age group. Secondly, they increased the qualifying times for nearly all of the 14/Over events. Let’s investigate how these two changes have affected this meet’s age and gender fairness.
To analyze the difficulty of making a cut, we’ll use our historical database of 23 million USA-S age group swims to calculate athlete acceptance likelihoods. The acceptance likelihood for an event is the number of USA-S athletes in the event’s age range that swam at least as fast the the event’s qualifying time, divided by the total number of USA-S athletes in the age range. For technical background, please review “The Fairness of Qualifying Times”. For analysis of the 2018 Zone Age Group Championship qualifying times, see “Zone Championships are Unfair”.
Our first plot shows that it’s easier for 14/Unders to qualify for EZ2020Y than EZ2019Y or EZ2018Y, and that it’s easier for boys than girls to qualify in all three meets. A 14/Under is expected to qualify for 0.43 events in EZ2020Y versus 0.36 in EZ2019Y and 0.41 in EZ2018Y.
Plotting the ratio of the boy’s expected acceptances to the girl’s shows that the unfair advantage enjoyed by 14/Under boys in EZ2019Y is reduced in EZ2020Y but still significant. A 14/under boy is expected to qualify for 1.16 times as many events as a girl in EZ2020Y, versus 1.21 times in EZ2019Y and 1.12 times in EZ2018Y. The plot also shows that 14/Under qualifying times were fairest in EZ2018Y.
Breaking down the EZ2020Y expected acceptances by age group and gender reveals that a boy is expected to qualify for more events than a girl in the 10/under and 11-12 age groups, while 13-14 girls and boys are expected to qualify for similar numbers of events.
To show this gender disparity more clearly, we plot the ratio of the boy’s expected acceptances to the girl’s. A boy is expected to qualify for 1.48 times as many events a girl in the 11-12 age group, while a girl is expected to qualify for 1.02 times as many events as a boy in the 13-14 age group.
The remainder of this post analyzes the individual events in each age group. We’ll learn that it’s easier for a boy to qualify for most events in this meet than a girl, including all the 10/Under and 11-12 events. The most unfair event in the meet is the 11-12 200 breaststroke, where a boy has 1.9 times the likelihood qualifying as a girl. We’ll also learn that most of the 14/Under events are more fair in EZ2020Y than EZ2019Y.
The easiest 10/Under event to qualify for in EZ2020Y is the 100yd breaststroke, for both boys and girls. The most difficult event to qualify for is the 100 IM; previously it was the 50 breaststroke. The disparity between easiest and most difficult events is reduced in EZ2020Y.
To quantify the gender disparity in the 10/Under qualifying times, we plot the ratio of the boy’s acceptance likelihood to the girl’s. This plot shows that, as in EZ2019Y and EZ2018Y, all 10/Under events favor boys at the expense of girls. The most unfair 10/Under events are the 100 IM and 200 freestyle, where a boy has more than 1.3 times greater likelihood of qualifying than a girl. The fairest 10/Under event is the 100 freestyle, where a boy has only 1.08 times greater likelihood of qualifying than a girl.
Boys are favored by a factor of 1.2 or greater in three of the twelve 10/Under EZ2020Y events; previously it was seven events. Moreover, ten of the twelve 10/Under events are more fair in EZ2020Y than they were in EZ2019Y. Only the 500 freestyle and 50 butterfly qualifying times are slightly less fair in EZ2020Y than EZ2019Y. To show that, we’ll provide a new type of plot.
The following plot directly compares the fairness of the 10/Under events in these two meets. Positive values indicate that an event’s qualifying times are more fair in EZ2020Y than they were in EZ2019Y; negative values indicate the opposite. Formally the values plotted are the absolute value of the logarithm of the EZ2019Y boys/girls acceptance ratio, minus the absolute value of the logarithm of the EZ2020Y boys/girls acceptance ratio. The plot shows that the fairness of seven 10/Under events has improved, with the 50yd freestyle improving the most. Only the 500yd freestyle and 50yd butterfly are less fair in EZ2020Y than they were in EZ2019Y, and only by a small amount.
Turning now to the 11-12 events, it’s easiest for boys to qualify in the 50 freestyle and for girls to qualify in the 500 freestyle. The most difficult event for boys to qualify in is the 200 breaststroke; for girls it is the 200 backstroke.
To quantify the gender disparity in these 11-12 qualifying times, we plot the ratio of the boy’s acceptance likelihood to the girl’s. This plot shows that, as in EZ2019Y and EZ2018Y, all fifteen 11-12 events favor boys at the expense of girls. The 200 backstroke and 50 breaststroke have the most unfair qualifying times, with a boy having 1.9 times greater likelihood of qualifying than a girl. Previously the most unfair event was the 50 freestyle, where a boy had 2.2 times greater likelihood of qualifying than a girl.
A boy has at least 1.5 times the likelihood of qualifying than a girl in seven of the fifteen EZ2020Y events; previously it was nine events. As shown by the following plot, twelve of the fifteen 11-12 events are more fair in EZ2020Y than they were in EZ2019Y, with the 50 freestyle having the greatest improvement and the 100 IM the least.
Recall that positive values in the “fairness increase” plots indicate that an event’s qualifying times are more fair in EZ2020Y than they were in EZ2019Y; negative values indicate the opposite. Formally the values plotted are the absolute value of the logarithm of the EZ2019Y boys/girls acceptance ratio, minus the absolute value of the logarithm of the EZ2020Y boys/girls acceptance ratio. Thus the preceding plot shows that the fairness of four 11-12 events has substantially improved, with the 50 freestyle improving the most. The only 11-12 event whose fairness has materially decreased is the 100 IM, where a boy now has 1.4 times the likelihood of qualifying as a girl; previously it was 1.2 times.
Looking next at the 13-14 events, we can see that the shorter freestyle events are again the easiest to qualify for, while the distance freestyle events are most difficult. This is the only age group for which it’s easier for a girl to qualify in most of these events than a boy.
To quantify the gender disparity in these 13-14 qualifying times, we’ll plot the logarithm of the ratio of the boy’s acceptance likelihood to the girl's. This plot shows that two of the 13-14 events substantially favor boys at the expense of girls (the 100 and 200 breaststroke), while three of the events substantially favor girls at the expense of boys (100 and 200 backstroke, and 200 IM). The most unfair event in this age group is the 100 backstroke, where a girl has exp(0.18) = 1.2 times the likelihood of qualifying than a boy.
As shown by the following plot, eleven of the fifteen 13-14 events are more fair in EZ2020Y than they were in EZ2019Y. Only the 100 and 200 breastroke are less fair in EZ2020Y than they were in EZ2019Y.
Recall that positive values in the “fairness increase” plots indicate that an event’s qualifying times are more fair in EZ2020Y than they were in EZ2019Y; negative values indicate the opposite. Formally the values plotted are the absolute value of the logarithm of the EZ2019Y boys/girls acceptance ratio, minus the absolute value of the logarithm of the EZ2020Y boys/girls acceptance ratio. Thus the preceding plot shows that the fairness of six 13-14 events has substantially improved, with the 100 backstroke improving the most. A girl now has 1.17 times the likelihood of qualifying in the 100 backstroke as a boy; previously it was 1.38.
We’ve seen that the 14/Under qualifying times for the Eastern Zone Short Course Age Group Championship are considerably fairer in 2020 than they were in 2019. Thirty three of the forty one events are more fair, four substantially so. Only one event is substantially less fair in EZ2020Y than it was in EZ2019Y (11-12 100 IM).
Nonetheless, this age group championship meet still favors 12/Under boys at the expense of girls. The least fair age group is 11-12, where a boy is expected to qualify for 1.48 times as many events as a girl.