Question 820584
Women are followed through delivery and classified as delivering preterm (< 37 weeks) or not.  The data are shown below.

Preterm Delivery	Experimental Drug	Standard Drug	Placebo
Yes	                      17	             23	          35
No	                      83	             77	          65

Is there a statistically significant difference in the proportions of women delivering preterm among the three treatment groups?  Run the test at a 5% level of significance
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Ho: The rows have the same proportions
Ha: The proportions are different
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I ran a Chi=Square program against the data and got the following::
test stat:: Chi-Sq = 8.9600
p-value = 0.0113
df = 2*1 = 2
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Conclusion:Since the p-value is less than 5%, reject Ho.
Conclusion: There is a statistical difference in the proportions.
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Cheers,
Stan H.
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