Chi suqare problem - large cells number and significant test validity

Posted by chengfoh on Mar 21, 2011; 8:04am
URL: http://spssx-discussion.165.s1.nabble.com/Chi-suqare-problem-large-cells-number-and-significant-test-validity-tp4210454.html

Hi everyone:

I am not a very experience user of SPSS and currently performing chi square test on my data to assess the association. Here is my case:

Row and column = 20 x 6 (different groups, I have try hard but there is not way to collapse them)
Variables: All are categorical (nominal)
Test perform = chi square test of independence
Sample size total = 150

due to the large cells number (row x column), the chi square test cannot give valid p value as too many cells have less than expected frequency <5 and violated one of the test's assumtion. In this case:

a) since the p value is not useful, can i pick the highly prevalence % from the cells and discuss only the result using descriptive statistic? will that be acceptable for write up?

b) in another data i have low cells number (3x3) and the p value is significant (p<0.05). for identifying which cell is the one giving the association, should i look at the adjusted standardized value at >2 or <2 to specifically pick cells that is actually significant?

Really need help from you guys who familiar with this.
thanks thousands.
Foh