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Why 75/25 medians? why not means?
Posted: Fri Jun 29, 2012 9:58 pm
by patentlybored
Why are admission percentile statistics (25/75th gpa/lsat) reported in terms of medians rather than a single mean? Reporting scores as 25/75 medians gives schools an incentive to admit splitters and reverse splitters, whom i have nothing against, but nonetheless LS's are given the ability to impove their admission statitistics by accepting either type of splittter. Why not report admission stats as a straight-up mean?
Re: Why 75/25 medians? why not means?
Posted: Fri Jun 29, 2012 10:29 pm
by IAFG
How would means disincentivize admitting splitters and reverse splitters?
Re: Why 75/25 medians? why not means?
Posted: Fri Jun 29, 2012 10:54 pm
by top30man
IAFG wrote:How would means disincentivize admitting splitters and reverse splitters?
Re: Why 75/25 medians? why not means?
Posted: Fri Jun 29, 2012 11:24 pm
by cd7573
Using means would provide a disadvantage to admitting super splitters Ex: 2.8 168's at WUSTL
Re: Why 75/25 medians? why not means?
Posted: Fri Jun 29, 2012 11:30 pm
by IAFG
cd7573 wrote:Using means would provide a disadvantage to admitting super splitters Ex: 2.8 168's at WUSTL
Means would be just as susceptible to manipulation, if not more. 25/75 at least requires that the middle 50% of admits are in a disclosed range.
Re: Why 75/25 medians? why not means?
Posted: Fri Jun 29, 2012 11:42 pm
by patentlybored
Using medians gives schools no incentive to admit a 2.8/176 vs. a 0.0/176. Either way, the 25% gpa is the same..,
Re: Why 75/25 medians? why not means?
Posted: Fri Jun 29, 2012 11:42 pm
by rayiner
cd7573 wrote:Using means would provide a disadvantage to admitting super splitters Ex: 2.8 168's at WUSTL
LOL @ 2.8/168 being a "super" splitter.
Re: Why 75/25 medians? why not means?
Posted: Fri Jun 29, 2012 11:46 pm
by IAFG
patentlybored wrote:Using medians gives schools no incentive to admit a 2.8/176 vs. a 0.0/176. Either way, the 25% gpa is the same..,
Well first, the USNWR ranking is based on the 50th percentile median and not the 25/75, so it doesn't matter at all. That aside, means would allow schools to admit half 160/4.0s and half 180/3.0s and have a 170/3.5 mean.
Re: Why 75/25 medians? why not means?
Posted: Fri Jun 29, 2012 11:55 pm
by cd7573
How many people get 180's?
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:01 am
by moonman157
But really though, why means and not medians? With medians, a 2.5/174 is the same as a 3.5/174. With means they're not the same at all, and one candidate is clearly better than the other.
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:03 am
by patentlybored
IAFG wrote:patentlybored wrote:Using medians gives schools no incentive to admit a 2.8/176 vs. a 0.0/176. Either way, the 25% gpa is the same..,
Well first, the USNWR ranking is based on the 50th percentile median and not the 25/75, so it doesn't matter at all. That aside, means would allow schools to admit half 160/4.0s and half 180/3.0s and have a 170/3.5 mean.
Hypothetically this is true, bUT how many 180/3.0 ss's really exist? F*** ill come up with more intelligible logic tomorrow while briefly sober
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:14 am
by IAFG
cd7573 wrote:How many people get 180's?
How many people graduate with 0.0s?!
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:15 am
by birdlaw117
With medians instead of means you at least know that at least half of people (or 25%, 75%, etc.) meet a certain threshold. A mean gives you no such real confidence in that fact. A school that admit 4 people with 175s and a 5th with a 150 would have a mean of 170, but an applicant with 170 doesn't appear to be in a very good position since 80% of students have a better LSAT.
Obviously with a sample size of 200+ this becomes pretty not important, but a data point is almost surely a better tool for making decisions in this context than a mean.
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:18 am
by cd7573
IAFG wrote:cd7573 wrote:How many people get 180's?
How many people graduate with 0.0s?!
Not my hypo... Try again
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:20 am
by cd7573
birdlaw117 wrote:With medians instead of means you at least know that at least half of people (or 25%, 75%, etc.) meet a certain threshold. A mean gives you no such real confidence in that fact. A school that admit 4 people with 175s and a 5th with a 150 would have a mean of 170, but an applicant with 170 doesn't appear to be in a very good position since 80% of students have a better LSAT.
Obviously with a sample size of 200+ this becomes pretty not important, but a data point is almost surely a better tool for making decisions in this context than a mean.
But the median here would be 175
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:20 am
by birdlaw117
cd7573 wrote:birdlaw117 wrote:With medians instead of means you at least know that at least half of people (or 25%, 75%, etc.) meet a certain threshold. A mean gives you no such real confidence in that fact. A school that admit 4 people with 175s and a 5th with a 150 would have a mean of 170, but an applicant with 170 doesn't appear to be in a very good position since 80% of students have a better LSAT.
Obviously with a sample size of 200+ this becomes pretty not important, but a data point is almost surely a better tool for making decisions in this context than a mean.
But the median here would be 175
Yes. Yes it would. And without a 175 you are very unlikely to be admitted. I don't see the problem.
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:31 am
by IAFG
cd7573 wrote:IAFG wrote:cd7573 wrote:How many people get 180's?
How many people graduate with 0.0s?!
Not my hypo... Try again
Go to hell.
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:32 am
by cd7573
IAFG wrote:cd7573 wrote:IAFG wrote:cd7573 wrote:How many people get 180's?
How many people graduate with 0.0s?!
Not my hypo... Try again
Go to hell.
.
Sure thing bud
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:35 am
by rayiner
What's the point of disincentivizing the admission of splitters? Does it make a material difference whether a school has a bunch of 2.9/175's versus 3.2/173's?
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:37 am
by IAFG
moonman157 wrote:But really though, why means and not medians? With medians, a 2.5/174 is the same as a 3.5/174. With means they're not the same at all, and one candidate is clearly better than the other.
Only if you believe that all 3.5s are better than all 2.5s. Which is obviously retarded.
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:38 am
by IAFG
rayiner wrote:What's the point of disincentivizing the admission of splitters? Does it make a material difference whether a school has a bunch of 2.9/175's versus 3.2/173's?
The point is, people with 164/3.5s are mad as fuck
Re: Why 75/25 medians? why not means?
Posted: Sat Jun 30, 2012 12:54 am
by rayiner
IAFG wrote:rayiner wrote:What's the point of disincentivizing the admission of splitters? Does it make a material difference whether a school has a bunch of 2.9/175's versus 3.2/173's?
The point is, people with 164/3.5s are mad as fuck
As long as 170+ LSAT's remain rare, schools will eat the 2.x super-splitters to get those LSAT's.