# Changeset 20488 in project

Ignore:
Timestamp:
09/24/10 13:56:43 (10 years ago)
Message:

Anonymous wiki edit for IP [86.129.203.107]:

File:
1 edited

Unmodified
Removed
• ## wiki/eggref/4/statistics

 r20487 === Descriptive statistics These functions provide information on a given list of numbers.  Note, the list of items does not have to be sorted. ; (mean items) : given a list of numbers, {{items}}, returns the arithmetic mean of the items (the sum of the numbers divided by the number of numbers). (mean '(1 2 3 4 5)) => 3 ; (geometric-mean items) : given a list of numbers, {{items}}, returns the geometric mean of the items (the result of multiplying the items together and then taking the nth root, where n is the number of items). (geometric-mean '(1 2 3 4 5)) => 2.60517108469735 ; (range ) : ; (percentile items n) : ; (variance items) : ; (standard-deviation items) : ; (coefficient-of-variation items) : ; (standard-error-of-the-mean ) : ; (mean-sd-n items) : ; (range items) : given a list of numbers, {{items}}, returns the difference between the biggest and the smallest value. (range '(5 1 2 3 4)) => 4 ; (percentile items percent) : given a list of numbers, {{items}}, and a percentage, {{percent}}, returns the item closest to the percent value if the items are sorted into order; the returned item may be in the list, or the average of adjacent values. (percentile '(1 2 3 4) 50) => 5/2 (percentile '(1 2 3 4) 67) => 3 ; (variance items) : given a list of numbers, {{items}}, returns the variance of the numbers. ; (standard-deviation items) : given a list of numbers, {{items}}, returns the standard deviation of the numbers. ; (coefficient-of-variation items) : given a list of numbers, {{items}}, returns 100 * (std-dev / mean) of the items. (coefficient-of-variation '(1 2 3 4)) => 51.6397779494322 ; (standard-error-of-the-mean items) : given a list of numbers, {{items}}, returns std-dev / sqrt(length items). (standard-error-of-the-mean '(1 2 3 4)) => 0.645497224367903 ; (mean-sd-n items) : given a list of numbers, {{items}}, returns three '''values''', one for the mean, one for the standard deviation, and one for the length of the list. > (mean-sd-n '(1 2 3 4)) 5/2 1.29099444873581 4 === Distributional functions
Note: See TracChangeset for help on using the changeset viewer.