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One difference between a randomized block experiment and a factorial experiment is that a randomized block experiment only has one observation per cell, whereas a factorial experiment almost always has more than one observation per cell.

The Central Limit Theorem states:  Consider a random sample of n observations selected from any population with mean μ and standard deviation σ.  If the sample size is sufficiently large, then the sampling distribution of the sample mean (X-bar) will be approximately a normal distribution with mean ________ and standard deviation _______.

The average height of a certain ornamental plant is 14 inches and the standard deviation of the heights is 2 inches.  Only 20% of the plants are expected to be less than X inches tall.  Find the value of X.

If we roll a single die, the sample points are 1, 2, 3, 4, 5, or 6.  Consider the following two events:      Event A:  toss an even number on the die      Event B:  toss a number less than or equal to 3 on the die List the sample points that would be included in the union of events A and B (i.e., A U B).

If the lower quartile is farther from the median than the upper quartile, the distribution of data is

A study published in The Journal of American Academy of Business examined whether the perception of service quality at five-star hotels in Jamaica differs by gender.  In order to compare the means of two populations (i.e., male vs. female guests), independent random samples were selected from each population, with the results shown in the table below.  Use these data to construct a 96% confidence interval for the difference in the two population means.   Males Females Sample size 127 114 Sample mean score 39.08 38.79 Sample standard deviation 6.73 6.94

In order to compare the means of two populations, independent random samples are selected from each population, with the results shown in the table below.  Use these data to construct a 98% confidence interval for the difference in the two population means.   Sample 1 Sample 2 Sample size 400 400 Sample mean 5,275 5,240 Sample standard dev. 150 200

In the 1970’s it was generally assumed that the mean birth weight of Angus beef cattle was 75 lb.  A researcher believes that, due to selection for increased size and growth rate in Angus, the average birth weight is now greater than 75 lb.  He obtains a random sample of n = 144 birth weights of Angus calves and calculates a sample mean of 85 lb and a sample standard deviation of 10 lb. State the null and alternative hypothesis that the researcher wants to test.

A dairy producer in Ohio wants to determine if the average milk production of her Holstein cows is greater than 18,000 lb of milk per lactation.  Therefore, she obtains a random sample of n = 100 milk production records from her herd and calculates a sample mean of 18,500 lb and a sample standard deviation of 3,500 lb. State the null and alternative hypotheses that she wants to test.

We are interested in comparing the mean supermarket prices of two leading colas in the Columbus area.  Assume that we have independent random samples of prices of six-packs at 8 supermarkets.  The data are shown in the following table: Supermarket      Brand 1       Brand 2  1                             $2.25          $2.30 2                               2.47            2.45 3                               2.38            2.44 4                               2.27            2.29 5                               2.15            2.25 6                               2.25            2.25 7                               2.36            2.42 8                               2.37            2.40 _______________________________________ Mean                       $2.3125       $2.3500 Standard deviation  $0.1007       $0.0859 _______________________________________ Find a 98% confidence interval for the difference in mean price of Brand 1 and Brand 2, assuming that these are independent random samples.