While reviewing some problems of statistics that I have already solved, I did the following questions, in a section on contingency tables call chi-square table to know if we reject the null hypothesis or not.Then call tables to obtain the value corresponding to
\!
\*SubsuperscriptBox[\(\[Chi]\), \(0.05, 3\), \(2\)]
which is 7.815, my doubt is can be calculated that value in mathematica?
thanks in advance
If you look up “chisquare distribution” in the Wolfram Documentation center you’ll find the necessary functions.
In[6]:= alpha = 0.05
df = 3
InverseCDF[ChiSquareDistribution[df], 1 - alpha]
Out[6]= 0.05
Out[7]= 3
Out[8]= 7.81473
Thank you Jim for your help to solve my question, is exactly what I needed,
Does this work with any significance level or just 0.05? Got the same results when changed alpha to 0.01, probably doing something wrong. I am also trying to replicate this calculator in Mathematica, but keep getting an error with degree of freedom calculation.
I get the appropriate values:
df = 3;
alpha = 0.01;
InverseCDF[ChiSquareDistribution[df], 1 - alpha]
(* 11.34486673014437` *)
alpha = 0.05;
InverseCDF[ChiSquareDistribution[df], 1 - alpha]
(* 7.814727903251181` *)
Also, there are many, many ways to mimic the calculator you reference. Here’s one way:
Manipulate[
InverseCDF[ChiSquareDistribution[df], 1 - \[Alpha]],
{{\[Alpha], 3}, {0.001, 0.005, 0.01, 0.05}},
{{df, 1}, 1, 120, 1, Appearance -> "Labeled"}]
Jim thank you very much. I actually refreshed and after changing the code it worked. Also appreciate the Mathematica code that works too!
