gagaouthu - 1 month ago 17

R Question

I tried to use the Kolmogorov-Smirnov test to test normality of a sample. This is a small simple example of what I do:

`x <- rnorm(1e5, 1, 2)`

ks.test(x, "pnorm")

Here is the result R gives me:

`One-sample Kolmogorov-Smirnov test`

data: x

D = 0.3427, p-value < 2.2e-16

alternative hypothesis: two-sided

The p-value is very low whereas the test should accept the null-hypothesis.

I do not understand why it does not work.

Answer Source

As pointed out in the `ks.test`

help, you have to give to the `ks.test`

function the arguments of `pnorm`

. If you do not precise mean and standard variation, the test is done on a standard gaussian distribution.

Here you should write:

```
ks.test(x, "pnorm", 1, 2) #or ks.test(x, "pnorm", mean=1, sd=2)
```