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When we perform hypothesis testing, we specify a value for α (alpha), where α represents:

A __________ – tailed hypothesis test is one in which the alternative hypothesis is directional and includes the less than or greater than symbol.

The normal approximation to a binomial probability distrubtion is reasonably good even for small sample sizes (say, n as small as 10) when p = 0.5 and the distribution of X is therefore symmetric about its mean.

An ____________ is an object (animal, plant, person, or thing) on which we collect measurements.

We are interested in estimating the average driving time of students who commute to Ohio State.  From data sampled previously, we believe that the longest driving time is 66 minutes and the shortest driving time is 18 minutes.  How many students who commute need to be included in our sample to order to be 98% confident that the estimated mean driving time will be within 4 minutes of the true population mean driving time?

Suppose x has a binomial probability distribution with n = 150 and p = 0.60.  Use the normal approximation to the binomial to find P(X>100).

A local consumer reporter wants to compare the average costs of grocery items purchased at three different supermarkets – Kroger, Giant Eagle, and Meier.  Prices (in dollars) were recorded for a sample of 60 randomly selected grocery items at each of the three supermarkets.  In order to reduce item-to-item variation, the prices were recorded for each item on the same day at each supermarket. Item                          Kroger    Giant Eagle    Meier     1) Big Thirst Towel      $1.21       $1.49          $1.59 2) Post Golden Crisp    2.78         2.99            3.35 3) Tylenol Tablets         5.98         5.29            5.98           .                              .              .                   .           .                              .              .                   . 59) Colgate Shave       0.94         1.10            1.19 60) Kidney Beans        0.45          0.56            0.38                                                                                   The results of the Analysis of Variance for this experiment are as follows: Source           df       SS            MS          F     Total                       222.21     Supermarket              2.64       1.32       39.23 Item                        215.59       3.65     108.54 Error                           3.97      0.0337                                                                                What are the correct degrees of freedom for total, supermarket, item, and error, respectively?

A bottling company needs to produce bottles that will hold 12 ounces of liquid for a local beer maker.  Periodically, the company receives complaints that their bottles are not holding enough liquid.  To test this claim, the bottling company randomly samples 15 bottles and finds the average amount of liquid held by the 15 bottles is 11.90 ounces and the standard deviation is 0.20 ounces. Using a level of significance of α = 0.05 and a one-tailed hypothesis test, find the appropriate rejection region.

We want to test the hypothesis that the mean yield of a particular variety of corn is less than 150 bushels per acre.  Therefore, we obtain the yields of a random sample of 20 corn fields in which this variety was planted. The average yield of the sample of fields was 140 bushels per acre with a standard deviation of 10 bushels per acre.  We want to test:    Ho:  μ = 150 bushels/acre    Ha:  μ < 150 bushels/acre using a significance level (α) = 0.10. What is the critical value that defines the boundary of the rejection region in this problem?

The sample space for an experiment is the collection of all of the sample points.