mirror of
https://git.FreeBSD.org/ports.git
synced 2024-10-29 21:39:24 +00:00
21 lines
799 B
Plaintext
21 lines
799 B
Plaintext
Suppose you flip a coin 100 times, and it turns up heads 70 times. Is
|
|
the coin fair?
|
|
|
|
Suppose you roll a die 100 times, and it shows 30 sixes. Is the die
|
|
loaded?
|
|
|
|
In statistics, the chi-square test calculates "how random" a series of
|
|
numbers is. But it doesn't simply say "yes" or "no". Instead, it gives
|
|
you a confidence interval, which sets upper and lower bounds on the
|
|
likelihood that the variation in your data is due to chance. See the
|
|
examples below.
|
|
|
|
There's just one function in this module: chisquare(). Instead of
|
|
returning the bounds on the confidence interval in a tidy little
|
|
two-element array, it returns an English string. This was a deliberate
|
|
design choice---many people misinterpret chi-square results, and the
|
|
string helps clarify the meaning.
|
|
|
|
-Anton
|
|
<tobez@tobez.org>
|