Determine whether the following statement is true or false: You can conclude definitively that mean teacher salary individually has no impact on the mean percentage of students passing the proficiency test, taking into account the effect of instructional spending per pupil, at a 1% level of significance based solely on but not actually computing the 99% confidence interval estimate for B,.

Suppose you are interested in studying regional differences in crime rates.  You take a random sample of 100 cities in the South, and find a mean crime rate of 55 with a sample variance of 5.78.  A sample of 100 cities in the North has a mean crime rate of 50 with a sample variance of 6.72.  Construct a 95% confidence interval around the difference in crime rates between the population of Southern cities and the population of Northern cities. Interpret, in words, the meaning of this interval.

A consumer product testing organization uses a survey of readers to obtain customer satisfaction ratings for the nation's largest supermarkets. Each survey respondent is asked to rate a specified supermarket based on a variety of factors such as: quality of products, selection, value, checkout efficiency, service, and store layout. An overall satisfaction score summarizes the rating for each respondent with 100 meaning the respondent is completely satisfied in terms of all factors. Suppose sample data representative of independent samples of two supermarkets' customers are shown below. Supermarket 1 Supermarket 2 n = 260 n, = 300 = 84 X, = 83 (a) Formulate the null and alternative hypotheses to test whether there is a difference between the population mean customer satisfaction scores for the two retailers. (Let u, = the population mean satisfaction score for Supermarket 1's customers, and let u, = the population mean satisfaction score for Supermarket 2's customers. Enter != for as…

A recent article published by the Wall Street Journal said the Cincinnati airport had the most expensive airfares among the largest airports in the US. While they had some statistics to support this statement, a statistician decided to investigate further. A sample of 46 flights originating in Cincinnati was selected, and the round-trip airfare for each flight was recorded. The sample data is summarized in the StatCrunch output below:    With 98% confidence, we estimate the mean airfare for flights out of Cincinnati is between $ and $. (Round the limits of your interval to 4 decimal places.) The mean airfare nationwide was reported as $376 for a round-trip ticket. Does the interval found above support the claim that Cincinnati has airfares which are more expensive than other airports in the US? The interval does not support the claim because the entire interval is not above $376. We can't make this conclusion based on a confidence interval. The interval does not support this claim…