Suppose that you want to perform a hypothesis test based on independent random samples to compare the means of two populations. You know that the two distributions of the variable under consideration have the same shape and may be normal. You take the two samples and find that the data for one of the samples contain outliers. Which procedure would you use? Explain your answer.

Bighorn sheep are beautiful wild animals found throughout the western United States. Let x be the age of a bighorn sheep (in years), and let y be the mortality rate (percent that die) for this age group. For example, x = 1, y = 14 means that 14% of the bighorn sheep between 1 and 2 years old died. A random sample of Arizona bighorn sheep gave the following information: x 1 2 3 4 5 y 13.8 19.3 14.4 19.6 20.0 Σx = 15; Σy = 87.1; Σx2 = 55; Σy2 = 1554.45; Σxy = 274b) Find the equation of the least-squares line. (Round your answers to two decimal places.) ŷ =  +  x (c) Find r. Find the coefficient of determination r2. (Round your answers to three decimal places.) r =   r2 =     d) Test the claim that the population correlation coefficient is positive at the 1% level of significance. (Round your test statistic to three decimal places.) t =

A researcher wants to explore the relationship between two variables: Time 1 and Time 2. Time 1 421 390 459 384 403 Time 2 A. O Matched pairs B. O Inference for regression C. O Two independent samples 400 383 436 362 392 If Time 1 is the time (in seconds) that it took for a random sample of five female college tennis players to run a mile, and Time 2 is the time (in seconds) of a random sample of five female college basketball players to run a mile, which of the following is the appropriate inference method to analyze these data?

Bighorn sheep are beautiful wild animals found throughout the western United States. Let x be the age of a bighorn sheep (in years), and let y be the mortality rate (percent that die) for this age group. For example, x = 1, y = 14 means that 14% of the bighorn sheep between 1 and 2 years old died. A random sample of Arizona bighorn sheep gave the following information: x 1 2 3 4 5 y 15.8 17.3 14.4 19.6 20.0   Σx = 15; Σy = 87.1; Σx2 = 55; Σy2 = 1,540.45; Σxy = 272 (a) Find x, y, b, and the equation of the least-squares line. (Round your answers for x and y to two decimal places. Round your least-squares estimates to three decimal places.) x =   y =   b =   ŷ =   +   x

Do larger universities tend to have more property crime? University crime statistics are affected by a variety of factors. The surrounding community, accessibility given to outside visitors, and many other factors influence crime rate. Let x be a variable that represents student enrollment (in thousands) on a university campus, and let y be a variable that represents the number of burglaries in a year on the university campus. A random sample of n = 8 universities in California gave the following information about enrollments and annual burglary incidents.x  12.3 28.6  24.5 14.3  7.5   27.7 16.2 20.1y   23   72     39      23    15    30    15    25   a) Compute r. (Round your answer to four decimal places.)

Do larger universities tend to have more property crime? University crime statistics are affected by a variety of factors. The surrounding community, accessibility given to outside visitors, and many other factors influence crime rate. Let x be a variable that represents student enrollment (in thousands) on a university campus, and let y be a variable that represents the number of burglaries in a year on the university campus. A random sample of n = 8 universities in California gave the following information about enrollments and annual burglary incidents. x 10.9 30.4 24.5 14.3 7.5 27.7 16.2 20.1 y 23 76 39 23 15 30 15 25   (a) Make a scatter diagram of the data. Then visualize the line you think best fits the data. A scatter diagram has a horizontal axis labeled "x (student enrollment (in thousands))" with values from 7.5 to 30.4 and a vertical axis labeled "y (annual number of burglaries)" with values from 15 to 76. The scatter diagram has 8 points. A pattern goes up and…

Q3, just parts d, e, f. (posted a, b, c  as a different question)

An athletic director proudly states that he has used the average GPAs of the university's sports teams and is predicting a high graduation rate for the teams. Why is this method unsafe? Choose the correct answer below. OA. This method is unsafe because the average GPA may differ for each team. Using the average of the average GPA of each team obscures the possibility that certain teams tend to perform less well in classes. B. This method is unsafe because there is more variation in the GPAs of the athletes than the average GPA of the university's sports teams. Strong students may offset weak students in calculating the average GPAS, which makes it appear more likely that most students are doing well. OC. This method is unsafe because it is dangerous to extrapolate into the future. Classes in university tend to become more difficult, which makes it less likely that the average GPA will hold as time goes on. D. This method is unsafe because there is a minimum GPA required to graduate. If…

Prices of diamonds are very sensitive to their weight (measured in carat). For example, the price of a 1 carat diamond tends to be much higher than the price of a 0.99 carats diamond. To study this phenomenon in more detail, we consider two random samples of diamonds, 0.99 carats and 1 carat, each sample of size 23. The average price of 0.99 carats diamonds in the sample is $4451, while the average price of 1 carat diamonds in the sample is $5681. From long-term studies, we know that both the prices of 0.99 carats diamonds and the prices of 1 carat diamonds are normally distributed with standard deviations oj = $1332 (0.99 carats) and o2 = $1613 (1 carat), respectively. (a) Carry out a hypothesis test at significance level 0.01 to evaluate whether the true average price µi of 0.99 carats diamonds is lower than the true average price µ2 of 1 carat diamonds. Specify Ho and Ha, the test statistic, and calculate the p-value or use p-value considerations to conclude. (b) Compute the type II…