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A researcher wanted to determine if the year the Star Spangled Banner was sung at a Super Bowl can be used as a linear predictor of the length of time (in seconds) the song was sung.  Data were collected and after checking all conditions, a linear regression analysis was produced.  Select Rguroo output is provided below.   What is the value of the t-test statistic hidden above?  Remember, the general form of the test statistic is (observed statistic – null parameter)/standard error.

Researchers are interested in the effect of distractions on work efficiency.  Forty college students were randomly selected to participate in an experiment in which half were randomly assigned to a quiet room and the other half to a room in which loud music was playing.  The students were asked to complete an easy Sudoku puzzle and their completion times were recorded.  A 95% confidence interval for the difference between mean completion times for the puzzle (music – no music) was found to be (5, 11) minutes.  Could this information be used to conclude that we should reject a null hypothesis of no difference in the average completion time between these two groups at a significance level of 0.05?

A random sample taken with replacement from the original sample and is the same size as the original sample is known as a:

Which of these statements does not contain a statistical mistake about correlation coefficient, r?

A gambler states that the probability of getting a “1” and a “2” when rolling two four-sided dice is 1/4 times 1/4 (or 1/16) because the dice are equally likely to land on any of the four sides and the results of the two dice rolls are independent.  Is this an example of a theoretical probability or an empirical probability?

A study of new cars to predict city gas mileage (miles per gallon) from their weight (pounds) resulted in a correlation coefficient of r = –0.4 and an r2 = 0.16. Based on this information, which of the following statements is correct?

Use the boxplots to answer the next three questions. The boxplots below represent movie runtimes (the length of a movie in minutes) for a random sample of 100 movies in each of four major genres (drama, action, comedy, children’s). Put the genres in order of their IQRs from least to greatest.

Which of the following samples taken from the sample 7, 27, 43, 49, 52, 60 could be a bootstrap sample?

What is extrapolation and why is it a bad idea in regression analysis?

A random sample of records of home sales from March 1 to July 1, 2010 from the files maintained by the Charlottesville Board of Realtors gives the Price (in dollars) and Size (in square feet) of 32 homes.  The regression model is as follows: Predicted Price = 47,820 + [ 61 × (Size) ] In this context, does the y-intercept have a reasonable interpretation?