McKeon et al 1952 investigate evidence that the environment

McKeon et al. [1952] investigate evidence that the environment is involved in infantile pyloric stenos is. The relationship between the age at onset of the symptoms in days, and the rank of the birth (first child, second child, etc.) was given as follows: Find the expected value (under independence) for cell (i = 2, j = 3). For this cell compute (observed - expected)2/ expected. The chi-square statistic is 13.91. What arc the degree s of freedom? What can you say about the p-value? In the paper, the authors present, the column percents, not the frequencies, as above. Fill in the missing values in both arrays below. The arrangement is the same as same first table. the adjusted residual p-values are What can you conclude? The authors note that the first two weeks appear to have different patterns. They also present the data as: For this table. X2 = 8.35. What are the degree s of freedom? What can you say about the p-value? Fill in the missing values in the adjusted residual table, p value table, and column permit table. Interpret the data. (f) Why is it crucial to know whether prior to seeing these data the investigators had hypothesized a difference in the parity distribution between the first two weeks and the remainder of the time period?(f) Why is it crucial to know whether prior to seeing these data the investigators had hypothesized a difference in the parity distribution between the first two weeks and the remainder of the time period?

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