A professor in the women’s studies program believes that the amount of smoking by women has increased in recent years. A complete census taken 2 years ago of women living in a neighbourng city showed...

A professor in the women’s studies program believes that the amount of smoking by women has increased in recent years. A complete census taken 2 years ago of women living in a neighbourng city showed that the mean number of cigarettes smoked daily by the women was 5.0 with a standard deviation of 2.2. To assess her belief, the professor determined the daily smoking rate of random sample of 121 women currently living in that city. The data show that the number of cigarettes smoked daily by the 121 women has a mean of 6.1 and a standard deviation of 2.7.

1. Is the professor’s belief correct? Assume a directional alternative hypothesis is appropriate and use an alpha = to 0.05_1-tailed in making your decision. Be sure that the most sensitive test is used to analyze the data.


2. Assume the population standard deviation is unknown and reanalyze the data using the same alpha level. What is your conclusion this time?


3. Determine the size of effect found in part b and provide an interpretation according to Cohen’s criteria