Sharon is interested in testing the differences between student populations at two different universities. If she randomly selects students from both universities, she is examining _____ sample(s). a. confounded   b. independent   c. single   d. dependent

The Bureau of Labor Statistics reports that the official unemployment rate for Black people was 10.4% and 4.7% for White people in February 2015. Select all correct answers for this question. O The samples of white and black people are independent. The explanatory variable is the unemployment rate. The response variable is the unemployment rate. The response variable is race.

A consumer magazine wants to compare the lifetimes of ballpoint pens of three different brands (measured in days). The magazine takes a random sample of pens of each type in the following table. What is the correct test statistic? Brand 1 Brand 2 Brand 3 382 181 238 242 140 257 216 162 241 319 218 213 a. F (2, 9) = 5.54 b.r = -.34 c. t (11) = 12.16 d.p = .027

Two computer users were discussing tablet computers. A higher proportion of people ages 16 to 29 use tablets than the proportion of people age 30 and older. The table below details the number of tablet owners for each age group. Test at the 1% level of significance. (For subscripts let 1 = 16-29 year old users, and 2 = 30 years old and older users.)   16–29 year olds 30 years old and older Own a Tablet 69 231 Sample Size 625 2,313 NOTE: If you are using a Student's t-distribution for the problem, including for paired data, you may assume that the underlying population is normally distributed. (In general, you must first prove that assumption, though.) Part (a) State the null hypothesis. H0: p1 < p2 H0: p1 > p2      H0: p1 ≠ p2 H0: p1 = p2 H0: p1 ≥ p2 Part (b) State the alternative hypothesis. Ha: p1 < p2 Ha: p1 ≠ p2      Ha: p1 = p2 Ha: p1 > p2 Ha: p1 ≤ p2 Part (c) In words, state what your random variable  P'1 − P'2  represents. P'1 −…