A local chess club claims that the length of time to play a game has a standard deviation of less than 13 minutes. Write sentences describing type I and type II errors for a hypothesis test of this claim. A type I error will occur if the actual standard deviation of the length of time to play a game is greater than or equal to v 13 minutes, but you reject the null hypothesis, Ho: o2 13 A type Il error will occur if the actual standard deviation of the length of time to play a game is less than the null hypothesis, |Ho: o > 13 13 minutes, but you fail to reject v

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The records of a casualty insurance company show that, in the past, its clients have had a mean of 1.9 auto accidents per day with a standard deviation of 0.04. The actuaries of the company claim that the standard deviation of the number of accidents per day is no longer equal to 0.04. Suppose that we want to carry out a hypothesis test to see if there is support for the actuaries' claim. State the null hypothesis H0 and the alternative hypothesisH1 that we would use for this test.

A psychologist finds that fidgety patients tap their fingers on average 500 times during a 2 hour period. You wish to test this claim for the same patients, but in a room decorated with soothing colors and soft lighting. You believe that a warmly decorated room may alter the fidgeting behavior, causing subjects to tap their fingers less than they do under normal conditions. A random sample of 400 patients has a mean of 420 taps and a standard error of 30 taps in a 2 hour period. Find the margin of error for the average tapping of fingers during a 2 hour period.

The brain volumes (cm³) of 20 brains have a mean of 1113.7 cm³ and a standard deviation of 128.9 cm³. Use the give standard deviation and the range rule of thumb to identify the limits separating values that are significantly low or significantly high. For such data, would a brain volume of 1361.5 cm³ be significantly high? 3 Significantly low values are cm³ or lower. (Type an integer or a decimal. Do not round.)

The records of a casualty insurance company show that, in the past, its clients have had a mean of  1.9 auto accidents per day with a standard deviation of 0.04 . The actuaries of the company claim that the standard deviation of the number of accidents per day is no longer equal to 0.04. Suppose that we want to carry out a hypothesis test to see if there is support for the actuaries' claim. State the null hypothesis H0 and the alternative hypothesis H1 that we would use for this test. H0 :  __? H1 : __?

The human resources department of a consulting firm gives a standard creativity test to a randomly selected group of new hires every year. This year, 65 new hires took the test and scored a mean of 113.2 points with a standard deviation of 13.4. Last year, 100 new hires took the test and scored a mean of 116.8 standard deviation of 14.6. Assume that the population standard deviations of the test scores of all new hires in the current year and the test scores of all new hires last year can be estimated by the sample standard deviations, as the samples used were quite large. Construct a 95% confidence interval points with for 4-, the difference between the mean test score u, of new hires from the current year and the mean test score , of new hires from last year. Then find the lower limit and upper limit of the 95% confidence interval. Carry your intermediate computations to at least three decimal places. Round your answers to at least two decimal places. (If necessary, consult a list of…