Originally Posted by

**bruxism** 2. you said "The P-value of 3.9 with 4 DF is .42, not at all significant". How do you calculate whether it is significant or not.

Either a cumulative chi-squared distribution calculator, or a set of

tables of critical values for the chi-squared distribution.

Below is the help text and example calculation from the system that

I use most frequently, when I'm not using the book of tables next to

my desk.

Code:

>
>help chidis
chidis is a builtin function.
normaldis(x) : returns the probability that a normally
distributed (mean 0, st.dev. 1) is less than x.
invnormaldis(p) : is the inverse.
chidis(x,n) : chi-distribution with n degrees of freedom.
tdis(x,n) : Student's t-distribution with n degrees of freedom.
invtdis(p,n) : the inverse.
fdis(x,n,m) : f-distribution with n and m degrees of freedom.
>
>chidis(3.9,2)
0.857726
>chidis(3.9,4)
0.580291
>