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Hypothesis Testing

Statistic Tests on Publisher and Manager Questions

10. The manager of a computer software company wishes to study the number of hours senior executives spend at their desktop computers by type of industry. The manager selected a sample of five executives from each of three industries. At the .05 significance level, can she conclude there is a difference in the mean number of hou

Vehicle Emissions Test

State DMV records indicate that of all vehicles undergoing emissions testing during the previous year, 70% passed on the first try. A random sample of 200 cars tested in a particular country during the current year yields 156 that passed on the initial test. Does this suggest that the true proportion for this country during the

True or False, Multiple Choice Questions

1. For a specific confidence interval, the larger the sample size, the smaller the maximum error of estimate will be. T 2. An estimator is consistent if, as the sample size decreases, the value of the estimator approaches the value of the parameter estimated. ____ T/F 3. When we reject the null hypothesis, we are c

Critical T-Value

Find the critical t-value that corresponds to c = 0.95 and n = 16.

Type I and Type II Errors

Type I and Type II Errors In this scenario, (1) formulate both a null and (2) research hypothesis and give an example of both a (3) Type I and (4) Type II error. Scenario: You are Supervisor or Research for Doggie Heaven Biscuit Company. Your scientists have developed a new dog biscuit for the treatment of doggie breath. I

Frequency Hypothesis Test

Please see attached file for full problem description. Please help with the areas in red, thanks! Frequency Hypothesis Test #4) Does it seem to you that people tend to be absent more on some days of the week than on others? Recently, a major biotechnology firm collected data with the hope of determining whether or not it

Test of Hypothesis for the Average Gasoline Price

The average gasoline price of one of the major oil companies has been $2,25 per gallon. Recently, the company has undertaken several efficiency measures in order to reduce prices. Management is interested in determing whether their efficiency measures have actually reduced prices. That is, the alternative hypothesis is that

One tailed test of Hypothesis

The McCollough Corporation, a producer of various kinds of batteries, has been producing D size batteries with a life expectancy of 87 hours. Due to an improved production process, the management believes that there has been an increase in the life expectancy of their D size batteries. A sample of 36 batteries showed an averag

A researcher wants to investigate the effects of prenatal alcohol on birth weight.

1. A researcher wants to investigate the effects of prenatal alcohol on birth weight. A random sample of n = 16 pregnant rats is obtained. The mother rats are given daily doses of alcohol. At birth, one pup is selected from each litter to produce a sample of n = 16 newborn rats. The average weight for the sample is 15 grams. The

Comparison of Samples

(a) state the decision rule, (b) compute the pooled estimate of the population variance, (c) compute the test statistic, (d) state your decision about the null hypothesis, and (e) estimate the p-value. The null and alternate hypotheses are: Ho: µ1 = µ2 Ha: µ1 ≠ µ2 Please use the five-step hyp

Standard Normal Random Variable

Let Z be a standard normal random variable. Determine the value of c such that P (Z > c) = 0.1251 is there a way to do this step by step so i can understand it?

Some hypothesis testing problems

Assume that a hypothesis test of the given claim will be conducted. The college Dean of Admissions claims that the times students require to earn a bachelors degree have a mean less than five years. Which equality/inequality (e.g., =, =<, etc.) would use in the Null Hypothesis? Assume that a hypothesis test of the giv

The mean age of bus drivers in Chicago is 54.5 years.

1. The mean age of bus drivers in Chicago is 54.5 years. If a hypothesis test is performed, how should you interpret a decision that fail to rejects the null hypothesis? A There is sufficient evidence to reject the claim mean = 54.5 B There is not sufficient to reject the claim mean = 54.5 C There is sufficient evidence to

Setting Up For Standard Deviation

The end of the year can be a time of rejoicing, a time of business, and a time of confusion. For most employers, it is a time to conduct open enrollment for its employees. For employers and employees, this can be a very confusing time with all of the options made available for the health care industry. The summary detailed be

Decision Rule

Please show in Excel spreadsheets 1) The restaurant chain claims that the waiting time of customers for service is normally distributed, with a mean of 3 minutes and a stdev of 1 minute. The quailty assurance department found in a sample of 50 customers at another place that the mean waiting time was 2.75 minutes. At a .05