180s and percentile ranks

User avatar
Reinhardt
Posts: 458
Joined: Fri May 18, 2007 2:27 am

Re: 180s and percentile ranks

Postby Reinhardt » Wed Feb 24, 2010 12:34 pm

99.98 is not correct anymore. The percentiles were shifted downward some, and now all LSAC says is that 179 and 180 are both 99.9.

User avatar
dutchstriker
Posts: 276
Joined: Wed Aug 12, 2009 3:15 pm

Re: 180s and percentile ranks

Postby dutchstriker » Wed Feb 24, 2010 2:38 pm

Reinhardt wrote:99.98 is not correct anymore. The percentiles were shifted downward some, and now all LSAC says is that 179 and 180 are both 99.9.

I'm guessing that's just rounding. I highly doubt that both 179 and 180 are 99.90. I'd be surprised to see a 180 go from the 99.98 percentile to the 99.90 percentile in just a few years. That's like going from 24 180s to 120 180s per year (if every year there were 120,000 tests administered -- I'm estimating). I'd guess it's more like 99.95 or 99.96 now.

febstriver
Posts: 29
Joined: Mon Dec 21, 2009 2:13 am

Re: 180s and percentile ranks

Postby febstriver » Wed Feb 24, 2010 2:59 pm

Zapatero wrote:
febstriver wrote:what if i am the only person who got 100 or 101 questions correct on any particular administration? what then? still 99th?


Don't worry, you won't.



you idiot

i did take stats

and we were taught that if we have the following scores (on a test out of 5), the cumulative frequencies would be as such:

n=10
x fx cf (percentile rank)
5 1 100%
4 2 90%
3 4 70%
2 2 30%
1 0 10%
0 1 10%

User avatar
Zapatero
Posts: 517
Joined: Thu Dec 04, 2008 7:14 pm

Re: 180s and percentile ranks

Postby Zapatero » Wed Feb 24, 2010 3:03 pm

febstriver wrote:
Zapatero wrote:
febstriver wrote:what if i am the only person who got 100 or 101 questions correct on any particular administration? what then? still 99th?


Don't worry, you won't.



you idiot

i did take stats

and we were taught that if we have the following scores (on a test out of 5), the cumulative frequencies would be as such:

n=10
x fx cf (percentile rank)
5 1 100%
4 2 90%
3 4 70%
2 2 30%
1 0 10%
0 1 10%


Zapatero wrote:
febstriver wrote:what if i am the only person who got 100 or 101 questions correct on any particular administration?


Don't worry, you won't.

letsdoit1982
Posts: 151
Joined: Thu Jan 28, 2010 11:59 pm

Re: 180s and percentile ranks

Postby letsdoit1982 » Wed Feb 24, 2010 3:03 pm

So exactly how many people on average get a 180? Like 30?

xcountryjunkie
Posts: 437
Joined: Tue Dec 01, 2009 7:52 pm

Re: 180s and percentile ranks

Postby xcountryjunkie » Wed Feb 24, 2010 3:04 pm

Flanker1067 wrote:
tomwatts wrote:
Flanker1067 wrote:I don't get the impression that 100 people a year get a 180 at all though. Think about that, Yale could theoretically make a class entirely of 180's. I don't believe this to be true.

I was under the impression that Yale could make a class mostly (though perhaps not entirely) of 180's if it felt like it, but there are too many people with good GPAs and good softs who are a little under that that they don't. Yale and the like do deny people with 180's sometimes.


Sometimes they do, but if there were a 100 180's, then they would only have to let in 25% of them to have a 75th percentile of 180. They aren't even close to that, I think it is 177, and I highly doubt they reject 75% of 180's.


You assume that all 180s apply to Yale. Surely this isn't true.

febstriver
Posts: 29
Joined: Mon Dec 21, 2009 2:13 am

Re: 180s and percentile ranks

Postby febstriver » Wed Feb 24, 2010 3:04 pm

Clearly, you are too stupid to get that when I say "what if I..." that I am not asking you to think about the probability of me getting that score but the probability of one getting that score. Also, your humor died on the last page, about 5 seconds after making that post.

kevin261186
Posts: 113
Joined: Fri Nov 13, 2009 3:45 pm

Re: 180s and percentile ranks

Postby kevin261186 » Wed Feb 24, 2010 3:07 pm

Zapatero wrote:
febstriver wrote:what if i am the only person who got 100 or 101 questions correct on any particular administration? what then? still 99th?


Don't worry, you won't.


LOL

User avatar
Zapatero
Posts: 517
Joined: Thu Dec 04, 2008 7:14 pm

Re: 180s and percentile ranks

Postby Zapatero » Wed Feb 24, 2010 3:08 pm

Your percentile rank is the proportion of people who have your score or worse. If 1 of 100 people have a 180, it's 99/100, or .99.

Regardless, this is a totally moot issue because the curve is determined before the test is even administered.

Flanker1067
Posts: 658
Joined: Tue Dec 29, 2009 12:47 pm

Re: 180s and percentile ranks

Postby Flanker1067 » Wed Feb 24, 2010 3:10 pm

Edit: I deleted this post because it is nonsense that does not need to be talked about on TLS. We can stop this conversation anytime.

This is interesting from a standpoint of just knowing the true numbers, but pretty much everything that has been said is speculation. Maybe you can email the LSAC and ask.

febstriver
Posts: 29
Joined: Mon Dec 21, 2009 2:13 am

Re: 180s and percentile ranks

Postby febstriver » Wed Feb 24, 2010 3:20 pm

Zapatero wrote:Your percentile rank is the proportion of people who have your score or worse. If 1 of 100 people have a 180, it's 99/100, or .99.

Regardless, this is a totally moot issue because the curve is determined before the test is even administered.


tyty


also, for kicks, i just calculated the prob of scoring 100/100 questions correct on the LSAT by pure guessing

pn = .2(100) = 20
pq = .8(100) = 80

z = X - pn / √ (100)(.2)(.8 )

z = 80 / 4 = 20

a z-score of 20??? 20 sd above the mean? my z-score table only goes up to 4 :(

what is the proportion of the tale 20 sd above the mean?

Woozy
Posts: 159
Joined: Sun Oct 18, 2009 2:29 pm

Re: 180s and percentile ranks

Postby Woozy » Wed Feb 24, 2010 3:26 pm

febstriver wrote:
Zapatero wrote:Your percentile rank is the proportion of people who have your score or worse. If 1 of 100 people have a 180, it's 99/100, or .99.

Regardless, this is a totally moot issue because the curve is determined before the test is even administered.


tyty


also, for kicks, i just calculated the prob of scoring 100/100 questions correct on the LSAT by pure guessing

pn = .2(100) = 20
pq = .8(100) = 80

z = X - pn / √ (100)(.2)(.8 )

z = 80 / 4 = 20

a z-score of 20??? 20 sd above the mean? my z-score table only goes up to 4 :(

what is the proportion of the tale 20 sd above the mean?


You're making it too hard on yourself.

0.2^100 = 1.27 x 10^-70

Pretty much equivalent to 0.




Return to “LSAT Prep and Discussion Forum”

Who is online

Users browsing this forum: Alexandros, dj9i27, Google [Bot], Instrumental, PresidentIJohnson and 8 guests