## Help with grade distribution/standard deviation

(Study Tips, Dealing With Stress, Maintaining a Social Life, Financial Aid, Internships, Bar Exam, Careers in Law . . . )
ohnowtf

Posts: 54
Joined: Thu Aug 21, 2008 4:05 am

### Help with grade distribution/standard deviation

my school is on a forced curve of 2.69 (b-)

only 2 grades in, but both Bs. we don't get ranked until our first year is completed.

any help with figuring out the distribution would be much appreciated

thesealocust

Posts: 8523
Joined: Mon Oct 20, 2008 8:50 pm

### Re: Help with grade distribution/standard deviation

edit: n/m
Last edited by thesealocust on Thu Jul 01, 2010 11:57 pm, edited 1 time in total.

imchuckbass58

Posts: 1245
Joined: Mon Mar 16, 2009 3:24 pm

### Re: Help with grade distribution/standard deviation

Sorry to hijack, but I'm trying to figure out our class ranking (i.e., what's median, what's top 20%, etc.) based on the curve. Can anyone help?

The data points I have are that 3.41 is typically top 30%, and that the curve is:

A+ discretionary, one per class at most
A ~10%
A- ~15%
B+ ~25%
B ~40%
B- and below ~10% (few if any Cs/Fs)

I may be having a math fail here, but I'm pretty sure that class standing will not equal the class curve, since people will have a smattering of high and low grades and thus regress towards the mean/median, but feel free to correct me if I'm wrong.

ohnowtf

Posts: 54
Joined: Thu Aug 21, 2008 4:05 am

### Re: Help with grade distribution/standard deviation

last year a 3.14 was top 25%. no data for this year, but I would assume it stays fairly consistent.

thesealocust

Posts: 8523
Joined: Mon Oct 20, 2008 8:50 pm

### Re: Help with grade distribution/standard deviation

edit: n/m
Last edited by thesealocust on Thu Jul 01, 2010 11:54 pm, edited 1 time in total.

imchuckbass58

Posts: 1245
Joined: Mon Mar 16, 2009 3:24 pm

### Re: Help with grade distribution/standard deviation

thesealocust wrote:
imchuckbass58 wrote:Sorry to hijack, but I'm trying to figure out our class ranking (i.e., what's median, what's top 20%, etc.) based on the curve. Can anyone help?

The data points I have are that 3.41 is typically top 30%, and that the curve is:

A+ discretionary, one per class at most
A ~10%
A- ~15%
B+ ~25%
B ~40%
B- and below ~10% (few if any Cs/Fs)

I may be having a math fail here, but I'm pretty sure that class standing will not equal the class curve, since people will have a smattering of high and low grades and thus regress towards the mean/median, but feel free to correct me if I'm wrong.

The secret of statistics is that it's fun to do with friends!

3.41 is top 30%. I need to know that the mean is. Look at your curve I'd guess it's 3.3? 3.2? You should be able to find out what the mean / median grade is at your school?

Funnily enough, they don't give us mean/median - that's primarily what I'm trying to figure out.

I do have another data point I just found, however, which is that 3.8 is typically top 3%.

thesealocust

Posts: 8523
Joined: Mon Oct 20, 2008 8:50 pm

### Re: Help with grade distribution/standard deviation

edit: n/m
Last edited by thesealocust on Thu Jul 01, 2010 11:53 pm, edited 1 time in total.

Black-Blue

Posts: 279
Joined: Wed Jan 14, 2009 10:46 pm

### Re: Help with grade distribution/standard deviation

You can't say unless you know the standard deviation

[quote]SD = .667 (highest I've seen, to be honest).[/quote
I think at my school, it's only .35

thesealocust

Posts: 8523
Joined: Mon Oct 20, 2008 8:50 pm

### Re: Help with grade distribution/standard deviation

edit: n/m
Last edited by thesealocust on Thu Jul 01, 2010 11:53 pm, edited 1 time in total.

1848

Posts: 12
Joined: Fri Nov 14, 2008 6:18 pm

### Re: Help with grade distribution/standard deviation

Hey thesealocust, would you mind doing mine? I tried doing it on my own but I can't figure out how to use the Z-chart (never took stat in high school or college).

My school's mean is 3.235.

20th percentile is 3.530

My GPA is 3.800

Where would that approximately place me?

thesealocust

Posts: 8523
Joined: Mon Oct 20, 2008 8:50 pm

### Re: Help with grade distribution/standard deviation

edit: n/m
Last edited by thesealocust on Thu Jul 01, 2010 11:53 pm, edited 1 time in total.

imchuckbass58

Posts: 1245
Joined: Mon Mar 16, 2009 3:24 pm

### Re: Help with grade distribution/standard deviation

Thanks, thesealocust!

1848

Posts: 12
Joined: Fri Nov 14, 2008 6:18 pm

### Re: Help with grade distribution/standard deviation

Thank you very much!

legends159

Posts: 1090
Joined: Thu Jul 12, 2007 4:12 pm

### Re: Help with grade distribution/standard deviation

I doubt it's possible but is there anyway to ballpark guess class rank on the H/P system?

Say an H is top 1/3 for each class.

mallard

Posts: 1075
Joined: Thu Aug 07, 2008 5:45 am

### Re: Help with grade distribution/standard deviation

legends159 wrote:I doubt it's possible but is there anyway to ballpark guess class rank on the H/P system?

Say an H is top 1/3 for each class.

I'm curious about this as well. Harvard's system is H for let's say top 40%, P for next 55%, and LP for about 5%. It's all discretionary but my guess is it tends to work out around that (just slightly more generous than the recommended curve). Any guess on what the top 10%, 25%, 50% of Hs would be?

legends159

Posts: 1090
Joined: Thu Jul 12, 2007 4:12 pm

### Re: Help with grade distribution/standard deviation

top 40% at HLS?

Is that a strict cutoff? At SLS it's strictly top 1/3; professors rank the students along a list based on final exam scores and then the registrar does the cutoff.

mallard

Posts: 1075
Joined: Thu Aug 07, 2008 5:45 am

### Re: Help with grade distribution/standard deviation

Like I said, it's mostly discretionary at this point.

acdisagod

Posts: 431
Joined: Fri Oct 16, 2009 12:46 pm

### Re: Help with grade distribution/standard deviation

good info, tag

DURS

Posts: 31
Joined: Tue Mar 25, 2008 2:57 pm

### Re: Help with grade distribution/standard deviation

If you don't mind, I'd like to know median/top 25%/top 10%

Mean: 2.95-3.05

A+ 4.3 1%
A 4.0 8%
A- 3.7 15%
B+ 3.3 25%
B 3.0 20%
B- 2.7 12%
C+ 2.3 7%
C 2.0 4%
C- 1.7 4%
D 1.0
F 0.0

Thanks for doing this, if you need more information let me know.

thesealocust

Posts: 8523
Joined: Mon Oct 20, 2008 8:50 pm

### Re: Help with grade distribution/standard deviation

edit: n/m
Last edited by thesealocust on Mon Dec 20, 2010 7:22 pm, edited 1 time in total.

DURS

Posts: 31
Joined: Tue Mar 25, 2008 2:57 pm

### Re: Help with grade distribution/standard deviation

thesealocust wrote:
DURS wrote:If you don't mind, I'd like to know median/top 25%/top 10%

Mean: 2.95-3.05

A+ 4.3 1%
A 4.0 8%
A- 3.7 15%
B+ 3.3 25%
B 3.0 20%
B- 2.7 12%
C+ 2.3 7%
C 2.0 4%
C- 1.7 4%
D 1.0
F 0.0

Thanks for doing this, if you need more information let me know.

I have to have a specific data point. The distrobution for each class won't help, I need to know something like "top X% = Y GPA".

Eyeballing it (and after doing all this math, my eyeball should be pretty good?) I'd peg top quarter in the 3.4 neighborhood and top 10% in the 3.6 neighborhood, but I could be way off base.

Last year median was 3.16.

eth3n

Posts: 284
Joined: Thu Jan 29, 2009 8:36 pm

### Re: Help with grade distribution/standard deviation

thesealocust wrote:That was the most impressive thing I have ever done.

I'm glad someone put AP stats to good use

thesealocust

Posts: 8523
Joined: Mon Oct 20, 2008 8:50 pm

### Re: Help with grade distribution/standard deviation

edit: n/m
Last edited by thesealocust on Thu Jul 01, 2010 11:53 pm, edited 1 time in total.

Zeph

Posts: 187
Joined: Wed Feb 04, 2009 12:22 pm

### Re: Help with grade distribution/standard deviation

acdisagod wrote:good info, tag

Good info indeed =)

thexfactor

Posts: 1291
Joined: Fri Sep 14, 2007 11:40 am

### Re: Help with grade distribution/standard deviation

I dont have any points but whats your estimate on my approx class rank?
avg is 3.0
10% A
15 % a-
17% B+
23% B
15% b-
10% C+
5% C
5% C-/ds

gpa 3.45