It is currently 17 Oct 2017, 21:17

### GMAT Club Daily Prep

#### Thank you for using the timer - this advanced tool can estimate your performance and suggest more practice questions. We have subscribed you to Daily Prep Questions via email.

Customized
for You

we will pick new questions that match your level based on your Timer History

Track

every week, we’ll send you an estimated GMAT score based on your performance

Practice
Pays

we will pick new questions that match your level based on your Timer History

# Events & Promotions

###### Events & Promotions in June
Open Detailed Calendar

# STATS

Author Message
Intern
Joined: 11 Jul 2003
Posts: 28

Kudos [?]: [0], given: 0

### Show Tags

26 Sep 2003, 14:11
This topic is locked. If you want to discuss this question please re-post it in the respective forum.

Can someone please explain the relation between arithmetic mean, variance and standard deviation, with examples. Thanks.

Does range come into picture here at all.

Thanks

Kudos [?]: [0], given: 0

CEO
Joined: 15 Aug 2003
Posts: 3454

Kudos [?]: 918 [0], given: 781

### Show Tags

26 Sep 2003, 17:45
Do a search in gmatclub, i had explained the concept of mean, std deviation to a member.

Variance is just the SQUARE of the Std. Dev ..thats much info is enough for purposes of the GMAT.

Does Range comes into the picture? well, it depends..

given a set of data, you can calculate many statistics related to that data...range is one of them...

look at a range problem posted today..it will give you an idea.

hope this helps

praetorian

Kudos [?]: 918 [0], given: 781

GMAT Instructor
Joined: 07 Jul 2003
Posts: 769

Kudos [?]: 234 [0], given: 0

Location: New York NY 10024
Schools: Haas, MFE; Anderson, MBA; USC, MSEE

### Show Tags

26 Sep 2003, 20:34
watchdog wrote:
Can someone please explain the relation between arithmetic mean, variance and standard deviation, with examples. Thanks.

Does range come into picture here at all.

Thanks

"Arithmetic mean" is synonomous with "average".

"Variance" is indeed the square of the "standard deviation". What is important to know in the GMAT is that these two numbers describe the "variability" of a group of numbers, i.e., how far apart they are scattered about their average. You will never be asked to compute a standard deviation, but you may be asked, given two groups of number, to identify which of the two has the larger standard deviation.

"Range" is simply the difference between the largest number and smallest number is a set. In general, the group with the larger range will have a larger standand deviation (but not always -- for example a group with the vast majority of its member near or at the mean with only two outliers than define the range).

In addition, you need to knwo what the "median" is. The median is the "middle" number is a group consisting of an odd number of numbers, and the average of the two middle numbers if there are an even number of numbers.

Hope this helps.
_________________

Best,

AkamaiBrah
Former Senior Instructor, Manhattan GMAT and VeritasPrep
Vice President, Midtown NYC Investment Bank, Structured Finance IT
MFE, Haas School of Business, UC Berkeley, Class of 2005
MBA, Anderson School of Management, UCLA, Class of 1993

Kudos [?]: 234 [0], given: 0

SVP
Joined: 03 Feb 2003
Posts: 1603

Kudos [?]: 303 [0], given: 0

### Show Tags

27 Sep 2003, 00:15
If you consider any part of ariphmetic progression, its ariphmetic mean and its median will be the same.

Kudos [?]: 303 [0], given: 0

Intern
Joined: 11 Jul 2003
Posts: 28

Kudos [?]: [0], given: 0

### Show Tags

28 Sep 2003, 02:02
Thanks.

The realtion, I guess, between the Standard Deviation and mean would be that, the SD revolves around the mean, the central tendency. Hence, if the mean (AM) moves the SD is effected.

am i right ?

Kudos [?]: [0], given: 0

28 Sep 2003, 02:02
Display posts from previous: Sort by