Dataset # |
Data |
Compared with |
Result |
RC1 |
983,383,2892 679,416,2625 134,84,570 |
Snedecor and Cochran,
Statistical Methods, Seventh ed., |
Agree with chi square of 40.54, p < .0000001, df=4 |
RC2 |
43,11 3,18 |
Epi Info chi sq=27.2225 Oswego/Vanilla by P=1.3505e-6 http://www.fourmilab.ch/rpkp/experiments/analysis/chiCalc.html for this chi sq value, p=1.8126e-7 RxC module gives 27.22 P=1.813e-7 |
Chi Square agrees (27.22) with Epi Info, but p value for 1 d.f. differs. RbyC does agree with the p-value from the url given, however. P=0.0000001813 |
|
|
Generated a 5 x 5 table that gave chi square of 45.5, with 16 df. P value was .0001162 and site above gave 0.0001 Generated another table with 4 d.f. chi sq 0 .4688. chiCalc gave p=0.9764, Rxc gave 0.9765. Hence the p from chi square appears to work correctly. |
|
By Andy Dean. Agreement is considered satisfactory if the first two significant figures agree, when a number, such as a p-value, is small.
Conclusions: R x C gives correct
results for the Snedecor/Cochran 3 x 3 table. The
calculation of p with 1 df
differs from Epi Info, Version 3, by an order of
magnitude, but agrees with p from a website in
R x C appears ready for use.