Interpreting StatsChi Test, specifically p-value

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What is the meaning of the P value in StatsCHi test? I am comparing two binned histograms with /S flag to denote the expected histogram.

statschitest/S/T=1 observed hist ,expected hist

n 24
df 23
Chi_Squared 18.1845
Critical 35.1725
P 0.747405

How to interpret the result?
Supriya Balaji wrote:

statschitest/S/T=1 observed hist ,expected hist

This command would not take you very far. I assume you meant
statschitest/S/T=1 observedHist ,expectedHist

or some variation thereof.

To understand the P-value I suggest that you try the following experiment:
1. Create a simple distribution:
Make/O/N=200 ggg
SetScale/P x -100,1,"", ggg
ggg=100*exp(-x^2/400)
Display ggg

2. Create a test distribution by copying ggg and adding some noise:
Duplicate/O ggg,exg
exg=round(exg+enoise(1))
appendTograph exg


3. Run the test:
StatsChiTest/T=1/S exg,ggg


4. Now increase the noise and test again:
exg=abs(round(exg+enoise(2)))
StatsChiTest/T=1/S exg,ggg


You can draw your own conclusions about P as a function of the noise level.

February 8, 2016 at 12:30 pm - Permalink