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Hypothesis Testing

Five step model of hypothesis testing for a counseling psychologist

A counseling psychologist is interested in determining whether the perception of a counselor's expertise is affected by the approach the counselor utilizes. In particular, the counseling psychologist is interested in contrasting a rational-emotive approach with a client-centered approach using an instrument that rates perceptio

Number of Crimes by Area

The Federal Government recently granted funds for a special program designed to reduce crime in high-crime areas. A study of the results of the program in eight high-crime areas of Miami, Florida, yielded the following results. Number of Crimes by Area A B C D E F G H Before 14 7 4 5 17 12

Hypothesis Testing

The cost of an e-commerce website can vary a great deal. A market research team hypothesized that the cost of an average website is $3500. Ho mean = $3,500 H1 mean ? $3,500 The sample data obtained showed the following costs: 2000, 3000, 3500, 3900, 6000, 7000, 10000, 12000, 14900, 19900, 6990, 9990, 2400 I n

Sampling Method and P-Values

A sociologist wanted to determine which academic subject high school students preferred. The hypotheses she wishes to test are: Ho: The percentage of female high school students who prefer mathematics is equal to the percentage of male students who prefer mathematics. H1: The percentage of female high school students who p

Probability Distribution and P-Values

A supermarket advertises that the waiting time spend by customers waiting in line at the cash register is uniform between 0 and 6 minutes. A number of customers complain that they wait in line too long for this to be true. Joel, the manager, decides to test whether the complains are justified by testing the hypotheses: Ho: µ

Probability and P-Values

There are two boxes, Box A and Box B. Box A has 40 tags with the number 1, 50 tags with the number 10, and 10 tags with the number 100. Box B has 40 tags with the number 100, 50 tags with the number 10, and 10 tags with the number 1. A box is picked at random and exactly one tag is drawn at random from that box. You do not know

Hypothesis Testing Question

Calculate and interpret the appropriate statistical test to determine the relationship between the following two variables. Use the five-step model of hypothesis testing to draw conclusions at the .05 level of significance Class Frequency of Drug Use Freshman Sophomore Junior Senior Never 16 8 30 28 1 or 2 20 25 22 1

Hypothesis Testing Question

Calculate and interpret the appropriate statistical test to determine the relationship between the following two variables. Use the five-step model of hypothesis testing to draw conclusions at the .05 level of significance Gender College Major Male Female Psychology 11 9 Educatio

Value of test statistic

A recent national survey found that high school students watched an average (mean) of 6.8 videos per month. A random sample of 36 college students revealed that the mean number of videos watched last month was 6.2, with a standard deviation of 0.5. At the .05 significance level, can we conclude that college students watch fewer

General Statistics

Am having difficulty plugging in the correct values into the formulas to be sued. If you can please provide step by step work out of the following problems. Begin with formula to be used and then work out so i can see where values go I would appreciate it. 2) A biologist suspected that in the 20-24 age group, males have a hi

Type I or Type II errors?

1) What is more important for the researcher to be concerned about in a study, Type I or Type II errors? Why? How does the type of data collected and the way in which the data is collected affect the possibility of Type I or Type II error? 2) Give two examples when practical significance would outweigh statistical signific

Significance, Hypothesis Test

1. In research, one often hopes to be able to state results using a confidence level that the results are valid of 90% or more. To test results to determine the confidence level, what is the significance of locating the test statistic in the tail that has a probability less than ά, which implies a confidence level of 1-(alp

Hypothesis test for the difference of population means: Paired comparisons

Hypothesis test for the difference of population means: Paired comparisons A personal computer manufacturer is interested in comparing assembly times for two keyboard assembly processes. Assembly times can vary considerably from worker to worker, and the company decides to eliminate this effect by selecting a random sample of

Tire Brands Testing

A consumer products testing group is evaluating two competing brands of tires, Brand 1 and Brand 2. Tread wear can vary considerably depending on the type of car, and the group is trying to eliminate this effect by installing the two brands on the same random sample of 8 cars. In particular, each car has one tire of each brand o

Hypothesis & Variables

1) Define what a hypothesis is and discuss the relationship between hypothesis testing and statistics. 2) List the five steps required to test a hypothesis of the mean. Be sure that all steps are in the correct sequence. Explain why the fifth step is the most important. 3) Discuss what independent and dependent variables

Testing the Manufacturing Quality Process

A manufacturer receives an order for light bulbs. The order requires the bulbs have a mean life span of 750 hours. The manufacturer selects a random sample of 25 light bulbs and find they have a mean life of 745 hours with a standard deviation of 15 hours. Test to see if the manufacturer is making acceptable light bulbs. Ass

P-Value of a tossed coin

A coin tossed 100 times and 530 heads appear. At a=0.05, test the claim that this is a non biased coin. Use a P-Value. Does this suggest the coin is fair? Show all of your work including curve and make your conclusion in verbiage a layman can understand.

Simple Analysis

Please see the small data attached. I need analysis showing following. 1) Mean calculation and T test calculation based on the data. I want ALL the steps on how you got the answers please. 2) 2 graphs made by excel showing comparison of mean between the control and unibrow group. and the other needs to show the rejec

Test Statistic for specialized medicine

In a survey of 500 doctors that practice specialized medicine, 20% felt that the government should control health care. In a sample of 800 doctors that were general practitioners, 30% felt the government should control health care. Test the claim that there is a difference in the proportions. State your hypothesis draw your c

Z Value and Test Statistic of a population

Assume that the data has a normal distribution and the number of observations is greater than fifty. Find the critical z value used to test the null hypothesis. =0.05 for a left-tailed test. -1.645 1.96 1.645 -1.96 Use the given information to find the P-value. The test statisti

Find the value of the linear correlation coefficient r.

A supplier of 3.5" disks clams that only 1% of the disks are defective. In a random sample of 600 disks, it is found that 3% are defective, but the supplier claims that this is simply a sample fluctuation. At the 0.01 level of significance, test the supplier's claim that 1% are defective. True or false: There is not sufficie

Hypothesis testing Problems

1. In 2002, approximately 177,000 tax returns were sampled to obtain estimates of various parameters. The mean income tax per return for the returns sampled was $9401. If, in reality, the population mean income tax per return in 2001 was $9489, 88 sampling error was made in estimating that parameter by the sample mean of $9401.

Mean, standard deviation and variance

We have two different samples - consisting of bags of M&M's. The first sample consists of 5 bags of M&M's with the following number of blue pieces in each bag 10, 11, 9,10,10. Calculate: A. The mean B. The standard deviation C. The variance The second sample consists of 10 bags with an average number of blue

Statistic Scenarios

Gun Violence. The Harris Poll asked a sample of 1009 adults which causes of death they thought would become more common in the future. Gun violence topped the list; 706 members of the sample thought deaths from guns would increase. Although the samples in national polls are not SRSs, they are similar enough that our method gi