Hypothesis Testing – Two or More Samples

Epidemiologists are researching the relationship between two levels of tobacco exposure and a positive diagnosis of esophageal cancer.

To complete this Application Assignment, answer the following problems:

Problem 7.1:

 

With SPSS, use the data set bd1.sav and the variables tob2 (dichotomized smoking status) and case (yes or no esophageal cancer) to test the following: Is there a difference in the incidence of esophageal cancer by tobacco exposure? (Hint: Are the exposure and the outcome variables independent of each other?) Include in your response the 5-step approach to hypothesis testing and an explanation of your decision to reject or fail to reject the null hypothesis.

Some research suggests that smoking by the mother during pregnancy can have an impact on the birth weight of the newborn.

Problem 7.2:

With SPSS, use the data set smok_bw.sav and the variables group (smoking status) and weight (mean birth weight) to address the following research question: Is there a difference in the mean birth weight of newborns based on the mother's smoking status during pregnancy?

1.Produce boxplots for each of the four groups mean birth weight.

2.Produce an ANOVA analysis for comparing the mean birth weights in the four groups.

3.Check the assumptions of Normality and Homogeneity of Variance

4.Conduct post-hoc comparisons using the LSD and Bonferroni methods.