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Cigarette smoking has important health consequences and is positively associated with heart and lung diseases. Less well known are the consequences of quitting smoking. A group of 10 nurses, from the Nurses’ Health Study, ages 50−54 years, had smoked at least 1 pack per day and quit for at least 6 years. The nurses reported their weight before and 6 years after quitting smoking. A commonly used measure of obesity that takes height and weight into account is BMI = wt/ht2 (in units of kg/m2). The BMI of the 10 women before and 6 years after quitting smoking are given in the last 2 columns of Table 8.32.
Table 8.32 BMI change in 50- to 54-year-old women over a 6-year period
Implement the test in Problem 8.131, and report a two-tailed p-value.
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