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Hypothesis Testing

Performing Hypothesis Testing

Using a hypothesis test with a well known 4 step procedure, state your conclusion for the 0.05 significance level: A. Based on responses from 1,015 randomly selected teens, which concluded that 44% of teens say grades are the greatest source of pressure, test the claim that fewer than half of all teens in the population feel

Prenatal alcohol hypothesis testing

Alcohol appears to be involved in a variety of birth defects, including low birth weight and retarded growth. A researcher would like to investigate the effect of prenatal alcohol on birth weight. A random sample of n=16 pregnancy rates is obtained. The mother rats are given daily doses of alcohol. The average weight for the sam

Null Hypothesis Statistics

Question: A researcher is using a sample for n=16 lab rats to examine the effect of a new diet drug. It's known that under regular circumstances these rats eat an average of 10 grams of food each day. The distribution of food consumption is normal with a standard deviation=4. The expected effect for the drug is to reduce food co

Statistical Significance

Your car gets 29 miles per gallon, one day you see your mileage average is 28 miles per gallon. Is this change statistically significantly and would you look for a reason or is it more of a variation attributed to chance? Another day you see your mileage is 22 miles per gallon - Is this change statistically significantly and

Is there a difference in proportion?

10. The manager of a computer software company wishes to study the number of hours top executives spend at their computer terminals 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 hours

Statistics : Hypothesis Testing, Test Statistic and Critical Region

Please help answer the following questions involving statistics. 1. Why do we use hypothesis testing? 2. What is a test statistic and how is it related to a critical value in hypothesis testing? 3. What is the critical region in hypothesis testing and why is it important?

Civics Hypothesis Testing

1) The nationwide mean price for a 3-year old Honda civic is $8,500 with a known standard deviation of $600. You check the newspaper and find nine 3-year old Civics in San Francisco selling for an average price of $9,000. You wonder whether the cost of Civics in San Francisco is higher than the rest of the nation. a) State yo

Test with P-Value

1. To compare the current attitudes toward prayer in the schools, a survey was conducted in four southern California counties {see attached for results}. State your hypotheses and conduct a test for homogeneity of attitudes among the four counties concerning prayer in the schools. Use a P-value in your conclusion. It would N

Hypothesis testing of tires and fuel economy

A taxi company manager is trying to decide if the use of radial tires instead of regular belted tires improves fuel economy. As a test, twelve cars are equipped with belted tires and the cars are driven over a prescribed test course. Without changing drivers the same cars were then equipped with the radial tires and driven once

Test of hypothesis: difference between proportions

A survey was completed to estimate the proportion of residents in support of constructing a new football stadium, at tax payer expense, to accommodate an NFL team in the LA area. It was found that 71 of 100 LA city residents favored the construction while 78 of 135 residents in the rest of the county were in support. Determine i

Research Methods / Statistics: 3. Four experimenters investigated the number of items recalled in a study of short-term memory when comparing some 25 year-old participants (Y) with some 65 year-old participants (O). (Use a two-tailed test.) a) Analyze the data as an independent samples design. b) Analyze the same data set as a matched pairs design.

See attachment for complete question. 3 Four experimenters investigated the number of items recalled in a study of short-term memory when comparing some 25 year-old participants (Y) with some 65 year-old participants (O). (Use a two-tailed test.) For this question you will be assigned data from one of these exp

Psychology Research Methods / Stats - Analyze the Data

2. Pigeons were trained to peck to obtain food. During extinction, one group of 21 pigeons was given a drug that inhibits the protein metabolism necessary for memory, while another group of 21 pigeons was not. The rate of pecking was then analyzed (use a one-tailed test). Does the drug increase the pigeons' pecking behaviour?

Design and Analysis of an Experiment Question

From time to time, one branch office of a company must make shipments to a certain branch office in another state. There are three package delivery services between the two cities where the branch offices are located. Since the price structures for the three delivery services are quite similar, the company wants to compare the d

Health Study on Aspirin

US physicians, health study consisted of two randomized clinical trails in one. the first tested the hypothesis that 345 milligrams of aspirin taken every other day reduces mortality from cardiovascular disease. The second tested whether 50 mg B-carotene taken on alternate days decreases the incidence of cancer. 261,248 male phy


1. A 4-day work week ensure that employees will have one more day that need not be spent at work. One possible result is a reduction in the average number of person leave days taken by employees on a 4-day work schedule. Do the data indicate that this is the case? use the p-value approach in testing to reach your conclusion.

Test of hypothesis, p value, confidence interval, linear regression

1. The wages for middle managers in a certain industry are thought to be no more than $45,000.00. A wage survey of 30 managers has a mean income of $46,260.00. Test the hypothesis at a 1% significance level. Does it appear that the average annual income is greater than $45,000.00? The population standard deviation is assumed

A question about null hypothesis is included.

In a study in which null hypothesis has been rejected, we should be aware of the possibility of ________ alternative hypotheses, Type II Errors, change due to new observations, all are correct This question is posed.

Multiple choice questions on testing of hypothesis

1.The power of a test is measured by its capability of a. rejecting a null hypothesis that is true. b. not rejecting a null hypothesis that is true. c. rejecting a null hypothesis that is false. d. not rejecting a null hypothesis that is false. 2. If an economist wishes to determine whethe

Statistical Analysis - Background Music

A researcher had the idea that background music might enhance performance on a math test and that the effect of music might depend on whether an individual is a music lover or not. She selected 50 music lovers and 50 control participants who did not listen to music on a regular basis. Half of the participants from each group t

Statistics: Multinomial, Neg Binomials and Hypothesis Testing

I have several questions I'm stuck on: 1. A production line produces good articles with probability .7, average ones with probability of .2, and defective ones with probability .1. Ten articles are selected. a) What is the probability of 8 good ones and 1 defective? b) What is the probability that there

Statistic Problems and Harassment

Employers sometimes seem to prefer executives who appear physically fit...Here are the data...c) You should also hesitate to conclude that increasing fitness causes an increase in ego strength. Explain why?

Null Hypothesis

2)Your company has recently changed suppliers of a certain raw material in an effort to reduce the number of defective units being produced at your plant. During the past year, the sampling has indicated a daily mean of 21.2 defective units. After testing the new suppliers raw materials for 30 days, it was found that the mean