arc/notes
1
0
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

vault backup: 2024-02-13 15:18:37

Browse Source
This commit is contained in:
zleyyij 2024-02-13 15:18:37 -07:00
parent 762fc0acc9
commit 9b77e5048c
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
education/statistics/Hypothesis Tests.md
View File

@ -70,6 +70,8 @@ Reliable investigators test their conclusions on an independent batch of data
## Goodness of fit tests ($\chi ^2$) ## Goodness of fit tests ($\chi ^2$)
This test is used when you have one qualitative variable with many categories, eg the (color, size, shape) of an (item). This test is used when you have one qualitative variable with many categories, eg the (color, size, shape) of an (item).
$$ \chi ^2 = sum(\frac{(obs_{freq} - exp_{freq})^2}{exp_{freq}}) $$
The $\chi^2$ curve does not follow the normal curve. It has a long right hand tail. As the degrees of freedom go up, the curves flatten out, and the hump moves out to the right. The $\chi^2$ curve does not follow the normal curve. It has a long right hand tail. As the degrees of freedom go up, the curves flatten out, and the hump moves out to the right.
$$ df = num_{terms} - 1 $$ $$ df = num_{terms} - 1 $$