Question: Smoking and survival, again. An observational study was conducted to examine the relationship between smoking and survival. Based on a survey conducted in Newcastle, United Kingdom, from 1972 to 1974, 1314 women were classified as either smokers or nonsmokers. In 1996, the researchers determined which of the women were still alive. The following table classifies the women by smoking status at the time of the original survey and by survival in 1996. The observed and expected counts are given side by side.
Observed Expected
Smoker Nonsmoker Smoker Nonsmoker
Alive 443 502 418.6 526.4
Dead 139 230 163.4 205.6
From these counts, we find that the chi-square statistic is 9.09. Does the study show that there is a statistically significant relationship between smoking status and survival?