irdebi1
Nov 9, 2011, 05:57 PM
What is the area in the left tail of the chi-square distribution for a value of 27.4884 and 15 degrees of freedom
jcaron2
Nov 10, 2011, 09:58 AM
According to the calculator on this page (http://www.fourmilab.ch/rpkp/experiments/analysis/chiCalc.html), the p-value (i.e. the probability of observing a test statistic at least as extreme as 27.4884) is 0.0249.
If you want to know the area under the curve to the left of that value, you're looking for the probability of observing a test statistic less extreme than 27.4884. That means you should subtract the p-value from 1.
1 - 0.0249 = 0.9751