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Hypothesis Testing

Hypothesis testing samples

What is a test of a proportion and give an example. What test do you use when one sample is small and the other large? Explain the difference between testing one sample with a parameter and testing two samples. What are the likes and differences between the ttable and the z table? When would you use a two pop

Problem set

Hypothesis Test for Effects of Marijuana Use on College Student: In a study of the effects of marijuana use , light and heavy users of marijuana in college were tested for memory recall with the results given below. Use a 0.05 significance level to test the claim that the population of heavy marijuana users has a standard deviat

Testing of Hypothesis

Question One. Data from the National Youth Survey on the number of assaults on students appears to indicate some gender differences. State the null and alternate hypotheses to test this theory, choose the appropriate test statistic and variance estimator and justify their choice, determine the critical value for the test statist

Statistics Word Problem

Questions 1- 10 refer to the following: The average weight of newborn infants at a hospital is 6.6 pounds. A sample of seven infants is randomly selected and their weights at birth are recorded as 9.0, 7.3, 6.0,8.8.,6.8, 8.4, and 6.6 pound. 1. What is the null hypothesis? Ho: The average weight of a baby is 6.6 2. What

Hypothesis testing: one way anova

In exercise 6 use the listed sample data from car crash experiments conducted b the National Transportation Safety Administration. New cars were purchased and crashed into a fixed barrier at 35 mi/hr. and the listed measurements were recorded for the dummy in the driver's seat. The subcompact cars are the Ford Escort, Honda Civ

The Rocky Mountain district sales manager of JCM, Inc.,

The Rocky Mountain district sales manager of JCM, Inc., a college book publishing company, claims that each of his sales representatives makes 40 calls on professors per week. Several reps said that this estimate is too low. To research the claim, a random sample of 28 reps revealed that the mean number of calls made last week w

Hypothesis testing

1. A social scientist claims that, on average, adults watch less than 26 hours of television per week. Data are collected on the television-viewing habits of 25 randomly selected individuals. This sample indicates that the mean number of hours per week of watching television for an individual is 22.4 hours. a) formulate a sui

To test the null hypothesis using 5 steps

You are the member of the marketing team at Sara Bellum's Pizza - the pizza for people who think too much!! Your mission is to evaluate two locations and determine if there is any difference in their suitability as locations for the next Sara Bellum Pizza restaurant. You will use a level of significance of 0.05. The loca

Sample Survey Design

8. A telephone survey utilized a sampling frame of 2000 numbers, and had a response rate of 25%. A question asked respondents if they preferred Brand 1, Brand 2, or Brand 3. According to the company, 35% of their customers preferred Brand 1, 35% preferred Brand 2, and 30% preferred Brand 3. The telephone survey found that 40%

Idle Work Hours & Baseball Data

1. The idle times during the eight-hour day shift and the night shift are to be compared. A time study revealed the following numbers of minutes of idle time for eight-hour periods. Day shift: 92, 103, 116, 81, 89 Night shift: 96, 114, 80, 82, 88, 91 Is there a difference in the idle time between the two shifts? T


Question 44: (2 points) A nurse measured the blood pressure of each person who visited her clinic. Following is a relative-frequency histogram for the systolic blood pressure readings for those people aged between 25 and 40. Use the histogram to answer the question. The blood pressure readings were given to the nearest whole n

The solution to Test of mean

1. A sample of 45 overweight men participated in an exercise program. At the conclusion of the program 32 had lost weight. At the .05 significance level, can we conclude the program is effective? a. State the null hypothesis and the alternate hypothesis. b. State the decision rule. c. Compute the value of the test statisti

Do we reject the null hypothesis?

What would be the conclusions from the ANOVA analysis below regarding the null hypothesis? Do we reject the null hypothesis? (see data in the attached file)

Size and power of the test

If X1,X2,...,Xn is a random sample of size n from a Bernoulli population with parameter p such that P(X=1)=1-P(X=0)=p. Then to test Ho: p=po, if the critical region is taken as X1+X2+...+Xn<=n-2. Find the size of the test and obtain an expression for power function.

Statistics: Hypothesis testing

An industry safety program was recently instituted in the pharmaceutical industry. The weekly average losses (averaged over 1 month) in man-hours due to accidents in 10 similar plants before and after the program are as follows: PLANT BEFORE AFTER 1 30.5 23.0 2 18.5 21.0 3 24.5 22.0 4 32.0 28.5 5 16.0 14.5 6 15.0 15.5

To test if there is significant difference in mean funds.

These are word problems concerning hypothesis theory. --- A financial planner wants to compare the yield of income- and growth-oriented mutual funds. Fifty thousand dollars is invested in each of a sample of 35 income-oriented and 40 growth-oriented funds. The mean increase for a two-year period for the income funds is 1100 w

Paired Samples Hypothesis Test of Outpatient Surgeries

There are three hospitals in the Tulsa, Oklahoma, area. The following data show the number of outpatient surgeries performed at each hospital last week. At the .05 significance level, can we conclude there is a difference in the mean number of surgeries performed by hospital or by day of the week? Day # of surgeries perfo

To test if the job satisfaction is more in men then in women

Using American Intellectual Union, AIU's large database of survey responses from the Unit 1 individual project, complete all of the following: 1. Work through a t-test to compare the means of two groups of data. One possible example is to compare the tenure of females to the tenure of males. Select one of the quantitative var

Level of Significance, Male/Female Examination Sample Scores

A sample of scores on an examination given to both males and females is: Males 72, 69, 98, 66, 85, 76, 79, 80, and 77 Females 81, 67, 90, 78, 81, 80, and 76 At the .01 level of significance, is the mean grade of the female students higher than that of the males?

Random variables, Expected Values, Chi-Square and Levels of Significance

Question 8: In business, time is money. A local entrepreneur wants to start a regional 24/7 package delivery service for businesses along the front range. A key planning assumption is that, with Colorado Springs as the collection and distribution hub, package delivery times throughout this region will follow a Normal Probabil

To test if the mean wages of teachers of Texas and Indiana state are different.

Past records suggest that the mean annual income, , of teachers in state of Arizona is greater than or equal to the mean annual income, , of teachers in Nevada. In a current study, a random sample of teachers from Arizona and an independent random sample of teachers from Nevada have been asked to report their mean annual inc

Difference in variation and significance levels.

Arbitron Media Research Inc, conducted a study of the radio listening habits of men and women. One facet of the study involved the mean listening time. It was discovered that the mean listening time for men was 35 minutes per day. The standard deviation of the sample was 10 men studied was 10 minutes per day. The mean listening

The Various Areas of Hypothesis Testing

(Statistical Techniques in Business & Economics, 11th ed.) Lind et al. Nonparametric statistical measures: a. compare population means or proportions to determine the relationship between variables. b. Can only be used with independent samples c. Allow for testing procedures that eliminate some of the unrealistic assumptions r

Testing of hypothesis mean differences

To test if mean utilization of citrus fruits by US people is at least 64%. See attached file for full problem description. Chpt#7 1) A citrus grower' s association believes that the mean utilization of fresh citrus fruits by people in US is a least 94 pounds per year. A ramdon sa

New pesticide testing

A pesticide company wanted to test the formulation of a new pest control chemical with respect to its effectiveness in killing roaches. The existing pesticide had an effectiveness rate of 70%. The existing chemical will be replaced if it can be proved that the new chemical is more effective. To test the new chemical, they tes

To test the if the mean and proportion are significantly different

Last year's mean hourly wage (in dollars) for all hospital clerical workers in a large state was See attached file for full problem description. An administrator for the state believes that this year's mean hourly wage for hospital clerical workers is greater than last year's mean. She hires statisticians to sample a number