I am running a Chisquare test using CHIDIST function in Excel. My observed and expected values are not identical however i get result 0 (zero). There are 75 observed values so I am using 74 freedom points. Not sure what I am doing wrong, any assistance would be appreciated.
The description of the
CHIDIST Excel function says:
Returns the right-tailed probability of the chi-squared distribution. The $\chi^2$ distribution is associated with a $\chi^2$ test. Use the $\chi^2$ test to compare observed and expected values.
This means that the p-value displayed by the function will be lower when the observed valuer are far away from the expected ones; and the p-value will be $1$ if the observed values match exactly the expected values. Therefore, since you are getting a very small p-value (displayed as zero due to the rounding done by Excel), I deduct that your data is distinct from the expected distribution.