Cranberry juice. It’s common folk wisdom that cranberries can help prevent urinary tract infections in women. A leading producer of cranberry juice would like to use this information in their next ad campaign, so they need evidence of this claim. In 2001, the British Medical Journal reported the results of a Finnish study in which three groups of 50 women were monitored for these infections over 6 months. One group drank cranberry juice daily, another group drank a lactobacillus drink, and the third group drank neither of those beverages, serving as a control group. In the control group, 18 women developed at least one infection compared with 20 of those who consumed the lactobacillus drink and only 8 of those who drank cranberry juice. Does this study provide supporting evidence for the value of cranberry juice in warding off urinary tract infections in women?

a) Select the appropriate procedure.

b) Check the assumptions.

c) State the hypotheses.

d) Test an appropriate hypothesis and state your results.

e) Interpret the meaning of the results and state a conclusion.

f) If you concluded that the groups are not the same, analyze the differences using the standardized residuals of your calculations.