IA IA Maths critical value percentage

[Pierre Reynaud]

Hi everyone
I need help for my IA in maths studies, I don't know how to work out the critical value :/ I think I missed something .
I followed this example until I got stock just before the section of Discussion/Validity
where they say "The x^2 critical value at 5% significance with 1 degree of freedom is 3.841. ... "
and I can't figure out where they got the "5%" percent >< and the "3.841"
here is the link of the example
http://fr.slideshare.net/BillyEgg/ib-math-studies-internal-assessment-final-draft

[kanata_zero]

Hi everyone

I need help for my IA in maths studies, I don't know how to work out the critical value :/ I think I missed something .

I followed this example until I got stock just before the section of Discussion/Validity

where they say "The x^2 critical value at 5% significance with 1 degree of freedom is 3.841. ... "

and I can't figure out where they got the "5%" percent >< and the "3.841"

here is the link of the example

http://fr.slideshare.net/BillyEgg/ib-math-studies-internal-assessment-final-draft

Significance level refers to how strong is the confidence of your test. The smaller the significance level, the higher your confidence. Which significance you take will depend on the person who does the test. Most people would think that a 1% significance level would be best but this would cause a high level of Type 2 errors. I'm not sure whether this is covered in Math studies or not.

The value 3.841 comes from the statistical X^2 table that can be found online.

Hope that helps

Edited December 3, 2013 by kanata_zero