A sample of n=9 scores is obtained from a normal population distribution with o-=12. The sample mean is M=60. a- with a two-tailed test and o=.05,use the sample data to test the hypothesis that the population mean is u=65. b- with a two-tailed test and o=.05, use the ample data to test the hypothesis that the population me
The value of the z-score that is obtained for a hypothesis test is influenced by several factors. Some factors influence the size of the numerator of the z -score and other factors influence the size of the standard error in the denominator. For each of the following, indicate whether the factor influences the numerator or denom
Numerous studies have shown that IQ scores have been increasing, generation by generation, for years (Flynn, 1984, 1999). The increase is called the Flynn Effect, and the data indicate that the increase appears to be about 7 points per decade. To demonstrate this phenomenon, a researcher obtains an IQ test that was written in
An automotive part must be machined to close tolerances to be acceptable to customers. Production specifications call for a maximum variance in the lengths of the parts of .0004. Suppose the sample variance for 3 parts turns out to be S2 = .0005. Use a=.05 to test whether the population variance specification is being violate
A law student, who want to check a professor's claim that convicted embezzlers spend on average 12.3 months in jail, takes a random sample of 36 such cases from court files. Using his results, namely, a mean of 10.8 months and a standard deviation of 3.9 months, test the hypothesis u=12.3 versus the alternative hypothesis u≠12
A study of 20 families in a certain large city showed that the average income was $33,210 in 2000 with a standard deviation of $1800. Test the hypothesis that the true average income in this city was actually $31,000 against the hypothesis that it was more. Use a level of significance of 5% (hint: This is a one-sided test).
The following data on annual rates of return were collected from five stocks listed on the New York Stock Exchange ("the big board") and five stocks listed on NASDAQ. At the .10 significance level, can we conclude that the annual rates of return are higher on the big board? NYSE.......Nasdaq 17.16.........15.80 17.08.......
Fry Brothers Heating and Air Conditioning, Inc. employs Larry Clark and George Murnen to make service calls to repair furnaces and air conditioning units in homes. Tom Fry, the owner, would like to know whether there is a difference in the mean number of service calls they make per day. A random sample of 40 days last year showe
Officials want to test whether drivers are obeying the posted speed limit of 65 mph. Sample: 55 vehicles. Average speed of sample: 69 miles Standard deviation: 7 miles 95% confidence level desired. Test the hypothesis that mean speed is less than or equal to 65 mph against its one-sided alternative. Please see the attac
An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the
A coin was flipped 60 times and came up heads 38 times. (a) At the .10 level of significance, is the coin biased toward heads? Show your decision rule and calculations. (b) Calculate a p-value and interpret it.
Faced with rising fax costs, a firm issued a guideline that stated that those transmissions of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 wi
List the data elements you are provided or can calculate. How do you use these data elements to determine how to solve the problem? Fry Brothers Heating and Air Conditioning, Inc. employs Larry Clark and George Murnen to make service calls to repair furnaces and air conditioning units in homes. Tom Fry, the owner, would like
A food processor is concerned that the 16 ounce can of sliced pineapple is being overfilled. The quality control department took a random sample of 50 cans and found that the arithmetic mean weight was 16.05 ounces, with a sample standard deviation of .03 ounce. At the 5% significance, can the hypothesis that the mean weight i
For this research question: Clearly identify the independent and dependent variables you would study. Determine whether a one-tail or two-tail test is most appropriate and explain why. Generate a testable null statistical hypothesis and an alternative statistical hypothesis. Select an alpha level of .05, .01, or .001 and
1. The value of the z-score that is obtained for a hypothesis test is influence by several factors. Some factors influence the size of the numerator of the z-score and the factors influence of the standard error in the denominator. For the following, indicate whether the factor influences the numerator or denominator of the z-
Are females more likely to develop high blood pressure than males? For this research question: Clearly identify the independent and dependent variables you would study. Determine whether a one-tail or two-tail test is most appropriate and explain why. Generate a testable null statistical hypothesis and an alternative
The mean shopping time for women with kids is 7.3 minutes. A random sample of women with children in a shopping store gave the following shopping times in minutes: 7.7 8.1 8.2 9.0 5.8 9.3 8.4 6.9 12.1 9.4 8.1 6.2 7.3 7.9 8.2 8.5 7.2 6.3 9.1 8.8 a) Verify that mean=8.1 minutes and s=1.4
Over the past 8 weeks the horse readings (in mg/100 ml)were 93, 88, 82, 105, 99, 110, 84, and 89. If the sample mean is 93.8, letting x be the random variable, we assume that x has a normal distribution and we know that the population standard deviation is 12.5. The mean glucose level for the horse should be u(population mean)=8
Fry Brothers Heating and Air Conditioning, Inc. employs Larry Clark and George Murnen to make service calls to repair furnaces and air conditioning units in homes. Tom Fry, the owner, would like to know whether there is a difference in the mean number of service calls they make per day. A random sample of 40 days last year showe
The following data on annual rates of return were collected from five stocks listed on the New York Stock Exchange ("the big board") and five stocks listed on NASDAQ. At the .10 significance level, can we conclude that the annual rates of return are higher on the big board? NYSE 17, 16 17, 08 15, 51 8, 43 25, 15 NASDA
The Damon family owns a large grape vineyard in western New York along Lake Erie. The grapevines must be sprayed at the beginning of the growing season to protect against various insects and diseases. Two new insecticides have just been marketed: Pernod 5 and Action...... [See attachment for complete question.]
A study was conducted using 139 students. One of the items studied was the maximun daily amount of alcohol consumed in the last month. Based on the data, are there differences between males and females in the maximum amount of alcohol consumed in any one day in the past month? Use alpha 0.5 Men
An auditor reviewed 25 oral surgery insurance claims from a particular surgical office, determining that the mean out-of-pocket patient billing above the reimbursed amount was $275.66 with a standard deviation of $78.11. (a) At the 5 percent level of significance, does this sample prove a violation of the guideline that the aver
Create a research question for one of the following groups: students, children or women. Include the independent and dependent variables you would study, an explanation of whether a one or two-tail test is most appropriate, your testable null and alternative hypothesis, and an explanation of which alpha level you would select an
The mean weight of newborn infants at a community hospital is 6.6 pounds. A sample of seven infants is randomly selected and their weights are recorded as 9.0; 7.3; 6.0; 8.8; 6.8; 8.4; and 6.6 pounds. What is the decision for a statistical significant change in average weights at birth at the 5% level of significance?
The claim that ""40% of those persons who retired from an industrial job before the age of 60 would return to work if a suitable job was available" is to be investigated at the 0.02 level of risk. If 74 out of the 200 workers sampled said they would return to work, what is our decision? (a) Do not reject the null hypothesis b
Create a research question for which the appropriate test of the statistical hypothesis would require the use of a z-score. The research question should include the independent and dependent variables you would study, an explanation of whether a one- or two-tail test is most appropriate, your testable null and alternative hyp
Hypothesis test for the difference of population means: Paired comparisons A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Though the two brands have been comparable in the past, some technological advances were recently made in the Brand 2 manufacturing process, and the cons
Calculate the test statistic and p-value for each sample. a. H0: μ = 60 versus H1: μ = 60, α = .025, ¯x = 63, σ= 8, n = 16 b. H0: μ ≥ 60 versus H1: μ < 60, α = .05, ¯x = 58, σ= 5, n = 25 c. H0: μ ≤ 60 versus H1: μ > 60, α = .05, ¯x = 65, σ= 8, n = 36