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Hypothesis Testing

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

Hypothesis Testing: 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 Medical Researchers

A medical researcher suspects that the pulse rate of smokers is higher than the pulse of non smokers. Use the sample statistics below to test the researchers suspicion. State your hypothesis, draw your curve, label your critical values and your test statistic, state your decision to accept or reject. Write your conclusion in

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

Students t test for the significance of Correlation Coefficient.

The heights and shoe sizes of the starting lineup of a tournament baseball team are listed below. Use a calculator to determine the correlation coefficient. Using a significance level of α=0.05, determine if there is a significant linear correlation between the heights and shoe sizes of the baseball team. Height

Statistic Problem

A statistically significant result occurs when the value of the test statistic falls in the rejection region. A result has practical significance when it is statistically significant and the result also is different enough from results expected under the null hypothesis to be important to the consumer of the results. By taking

Hypothesis Identification Article Analysis

Please use the attached PDF article to help me solve the following problem: Prepare an analysis of your selected article. Start by identifying the hypothesis described in the article, and explain how the hypothesis statement was used in the study. Be sure to properly cite your article, and be prepared to discuss your analysis

Hypothesis Testing and Significance Level

1. If you were to conduct right-tailed hypothesis test at 5% significance level, you choose the critical value this way. Assuming that the null hypothesis is true, you will find the value of the test statistic for which the probability of obtaining a value less than the specified value is 0.05. Is this true? Explain answer.

Probability/statistics/z table/student's t

1. 20 problems 2. If confidence level is not given, assume 95% 3. Please show calculation using formula and using appropriate z table, student's t table, or Poisson table, etc. See attached file for full problem description.

Parametric or Nonparametric Data

Please help me with the following: 1. The average life span of a dog is proportational to the amount of calcium consumed. P- Parametric data or NP - nonparametric data? 2. A study of vehicle accidents on a military installation compared to driver's rank. P- Parametric data or NP - nonparametric data?

Hypothesis testing problems

1. The graph portrays the decision criterion for a hypothesis. Determine the significance level. 2. 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 a null hypothesis if: = 0.05 and the test is right-tailed. 3. Use

Hypothesis Analysis traditional and P value method

Problem #6 Investor's Business Daily The mean length of a work week for the population of workers was reported to be 39.2 hours (Investor's Business Daily, September 11, 2000). Suppose that we would like to take a current sample of workers to see whether the mean length of a work week has changed from the previously reported 39

Hypothesis Test: Daycare Charge

You want to check the claim that the Laurelhurst area has higher day care charges then the non Laurelhurst areas. Test the hypothesis that the Laurelhurst area has a higher daycare charge per month from the date below. LAURELHURST NON-LAURELHURST 500

Goodness of Fitness

You own a small tea company, Sweet Leaf, NASDQ ticker symbol LEAF. You are looking at marketing costs versus benefits. Your production manager says it doesn't matter which tea you produce, all tea is the same. You say otherwise. You hire a consumer research firm headed my Matt Stat. He randomly interviews 100 consumers of your t

Random Sample - Test Scores

In the past, 38% of all students pass the state high school exam on their first try. A school posts a first time passing rate of 56%. If the school had a sample size of 324, is the school's 56% really any different that the state's 38%?

proportion testing for SAT scores

Two high school principals are arguing about who has the better school. This principal for Hard Rock High, Desi Mall, draws a random sample of 100 of her seniors and finds that 75% scored above 650 on the math portion of the SAT. Sharon N. Formation, the principal of Preppy Magnet School, drew a sample of 25 students and found t

Description of Statistics - Hypothesis Test

North Carolina State University looked at the factors that affect the success of students in a required chemical engineering course. Students must get a C or better in the course in order to continue as chemical engineering majors. There were 65 students from urban or suburban backgrounds, and 52 of these students succeeded. Ano

Statistics on Heart Disease

#3 Heart disease patients often experience spasms of the coronary arteries. Because biological amines such as serotonin may play a role in these spasms, a research team measured serotonin levels post-mortem from patients who died of heart disease and from a control group that died of other causes. The data are summarized in t

State Null and Alternate Hypothesis

1. A sample of 64 observations is selected from a normal population. The sample mean is 216, and the sample standard deviation is 15. Conduct the following test of hypothesis sing the .03 significance level. H0: µ ≥220 H1: µ < 220 a. State the null and the alternate hypothesis b. State the decision rule c. Compute

homogeneity of variance assumption

1. Describe the general characteristics of a research study for which an independent-measures t would be the appropriate test statistics 2. What is measured by the estimated standard error that is used for the independent-measures t statistic? 3. Describe the homogeneity of variance assumption, and explain why it is import

Statistical Analysis of Quaker Oats

See the attached file. Quaker Oats is contemplating changing the shape of its box from the quaint cylinder presently in use. Different random samples were selected from five stores of similar size in the same region, and one of the candidate boxes was substituted for the cylinder for several days. The following results were o