In 2004, two groups of college age students were asked how many drinks they had on a day in which they were drinking. Group A was above the legal drinking age and Group B was below the legal drinking age. The below drinking age group had a sample mean of 1.2 drinks and the above drinking age group had a sample mean of 2.17 drinks. What is the point estimate of µb  – μa ?  

According to a recent Gallup-Purdue Index study, 719 out of 1564 SEC Conference graduates are deeply interested in the work that they are doing in their jobs.  Calculate a 95% confidence interval for the proportion of all SEC Conference graduates that are deeply interest in the work that they are doing in their jobs. Write out in words what the confidence interval means.

A survey of shoppers is planned to determine what percentage use credit cards.  Prior surveys suggest 63% of all shoppers use credit cards.  How many randomly selected shoppers must we survey in order to estimate the proportion of shoppers who use credit cards to within 4% with 95% confidence?

It is recommended that adults get 8 hours of sleep each night.  A researcher hypothesized college students got less than the recommended number of hours of sleep each night, on average.  The researcher randomly sampled 20 college students and found no evidence to reject the null hypothesis at the 5% significance level.  What is true regarding the p-value from this hypothesis test?

A group of eight individuals with high cholesterol levels were given a new drug that was designed to lower cholesterol levels. Total cholesterol levels, in mg/dL, were measured before and after treatment. The results are given in the table below.         Subject                                          Before Treatment                               After Treatment 1 283 215 2 299 206 3 274 187 4 284 212                         5 248 178 6 275 212 7 293 192 8 277 196   Using a 1% level of significance, perform a hypothesis test to determine if the treatment is effective in lowering cholesterol levels.

Statistics published by Monitoring the Future (www.monitoringthefuture.org) show that the percentage of 12th graders who have used marijuana in 2003 is 46.1% versus 36.7% in 1991. A 95% confidence interval for p2003 – p1991 is given by (0.08, 0.11) where p2003 is the proportion of 12th graders who had used marijuana in 2003 and p1991 is the proportion of 12th graders who had used marijuana in 1991. Based on this interval, what can you conclude about the proportion of 12th graders who have used marijuana in 2003 versus 1991?

You have been asked to do a home consult on a 91-year-old recently widowed female with a diagnosis of right shoulder pain. In your examination, you notice crops of erythematous vesicles along her right medial forearm. The patient reports the areas is painful and severely pruritic. The most likely cause of her skin condition is:

Which of the following are common pigmentary disorders?

Which STI is caused by a protozoan?

Which viral infection presents as a painful, dermatomal rash?