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Hypothesis Testing

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

Hypothesis Testing : Proportion and Solutions in Research Issue

A comparison between products manufactured in China VS Mexico and their perceived quality to the US consumer based on manufacturing location. We can state that 75% of American's perceive that a product (non-electronic) manufactured in Mexico is of better quality than a product manufactured in China. To do the testing we just ask

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 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

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

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 questions

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

Goodness-of-fit Test : Hypothesis Testing

Goodness of fit test : A student was given a die but he had no idea whether or not it was a fair die. He threw the die 480 times and each outcome was recorded. The results are given in the following table. xi 1 2 3 4 5 6 Oi 80 105 95 64 79 57 Test, at the 5% level of significance, whether or not this die is fair. You must s

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

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

Hypothesis Test - Frozen Dinner

Your company manufactures low calorie frozen dinners. The advertised calorie content is 200 calories. A consumer activist group, FACT: fat and calories tribunal, is claiming that your product is not consistent. In fact, they contain more than 200 calories. Run a hypothesis test proving that your dinners are less then 200 calorie

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%?