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Hypothesis Testing

Statistics - Hypothesis Testing Questions Responses

See attached file for full problem description. 1. In city D, 141 of the 300 randomly selected customers were aware of product; whereas in city O, 125 of 250 randomly selected consumers were aware of the product. Based on these data, the 95% margin of error is .084 or 8.4%. a. form the 95% confidence interval of the differen

Ethics is Statistics

Explain how important it is to report your data honestly and not manipulate the data in an attempt to prove your hypothesis. In addition, explain why it is important to ensure that your participants understand fully the extent of the research before you begin.

Hypothesis Testing: Evaluating the P-Value

Question: Determine the p-value for each of the following hypothesis-testing situations: a. H0: p = 0.25 and Ha: p does not = 0.25; z test value = 1.84 b. H0: u >/= 13.5 and Ha: u < 13.5; t test value = -1.94 d.f. = 10

Point Estimate of the Population Mean and Margin of Error

How do I calculate the point estimate of the population mean and the margin of error for a 90% confidence interval. If I were given the example of lengths of running distances for 30 people (miles), such as 12, 18, 20, 15, 6, 8, 9, 10, 2, 1, 12, 33, 20, 18, 15, 15, 6, 9, 9, 10, 10, 12, 22, 24, 6, 7, 8, 8, 9, 10.

Two probability and hypothesis testing questions

Question 5: The weight of bags "checked in" is normal, with a mean of 30 pounds and a standard deviation of 9 pounds. a) What is the probability that a randomly selected bag will weigh more than 48 pounds? b) What is the probability that the total weight of 4 bags will be more than 192 pounds? c) Find the probability th

formal 5-step hypothesis testing model

An associate asks for your help in deciphering the following Anova table, indicating that a test of means was performed on the average age of people at three different locations. Unfortunately the person leaves before you can get any further explanation or detail, but you know the results must be presented before senior staff w

Compare insurance amounts and customer satisfaction among BankTen customers

See attached data file. Before you write your report for Cindy, use the Customer Data template in Materials below to work with the data, as follows: Estimate the total market size of the insurance business for the target population (i.e., estimate the total dollar volume of the insurance business done by the entire popula

Test Hypothesis

5. To test the null hypothesis that the average lifetime for a particular brand of bulb is 750 hours versus the alternative that the average lifetime is different from 750 hours, a sample of 75 bulbs is used. If the standard deviation is 50 hours and alpha is equal to 0.01, what values for x-bar will result in rejection of the

Advanced Hypothesis

Sample size n = 3,200. 41% think that outsourcing is bad for U.S. businesses. 56% think outsourcing is good for U.S. businesses. 3% do not know. I think that the percent of those that think is good is lower. Assumption: Suppose that outsourcing can be deemed feasible if at least 73% of the population thinks that outsourci

Hhypothesis Testing

8.17 Bowman Electronics sells electronic components for car stereos. They claim that the average life of a component exceeds 4,000 hours. To test this claim, they have selected a random sample of n = 12 of their components and have traced the life between installation and failure. The following data were obtained: 1,973

Hypothesis Tests for Proportions

8.8 Given the following null and alternative hypothesis Ho: &#956; = 1,346 HA: &#956; &#8800; 1,346 &#945; = 0.05 and _ X = 1,338 &#963; = 90 n =60 a. establish the appropriate decision rule based on z as a test statistic b. indicate the appropriate decision based on the sample information and

Estimating a Population Proportion Margins of Error

For each of the following situations, determine the margin of error: _ a. X = 2.47, and n = 12, confidence coefficient = 0.98, &#963; = 6.58 _ b. X = 13.9, and n = 21, confidence coefficient = 0.95, s = 2.33 _ c. X = 114.7, and n = 500, confidence coefficient = 0.80, s = 15.6 If you wis

Standardized Test Statistic

1. Find the standardized test statistic to test the claim that mean1 = mean 2. Two samples are randomly selected from each population. The sample statistics are given below. n1 = 50 n2 = 6 x1 = 31 x2 = 29 s1 = 1.5 s2 = 1.9 x has a line above it 2. In a recent survey in gun control laws, a random sample of 1000 women sho

Hypothesis Testing

Problem: Past records suggest that the mean annual income, mu1, of teachers in state of pennsylvania is less than or equal to the mean annual income, mu2, of teachers in Illinois. In a current study, a random sample of 15 teachers from pennsylvania and an independent random sample of 15 teachers from Illinois have been asked

Hypothesis Testing

EXAMPLE 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 (test) that college

Null Hypothesis and Type II Errors

Question One personality test available on the World Wide Web has a subsection designed to assess the "honesty" of the test-taker. After taking the test and seeing your score for this subsection, you're interested in the mean score, mu, among the general population on this subsection. The website reports that mu is 142, but

Null Hypothesis Georgia Teachers

Past records suggest that the mean annual income, mu 1, of teachers in state of Georgia is greater than or equal to the mean annual income, mu 2, of teachers in Indiana. In a current study, a random sample of 20 teachers from Georgia and an independent random sample of 20 teachers from Indiana have been asked to report their mea

Hypothesis Testing and Levels of Significance

18. The management of White Industries is considering a new method of assembling its golf cart. The present method requires 42.3 minutes, on the average, to assemble a cart. The mean assembly time for a random sample of 24 carts, using the new method, was 40.6 minutes, and the standard deviation of the sample was 2.7. Using the

Specificity and sensitivity rationale

Two pediatricians want to investigate a new laboratory test that identifies streptococcal infections. Dr. J uses the standard culture test, which has a sensitivity of 90% and a specificity of 96%. Dr. M uses the new test, which is 96% sensitive and 96% specific. Review answer is Dr. J will correctly identify fewer people with

Prevalence of disease: False Positive

A screening test is used in the same way in two similar populations, but the proportion of false-positive results among those who test positive in population A is lower than that among those who test positive in population B. What is the likely explanation for this finding? Answer is The prevalence of disease is higher in popu

Probability of Occurrence

Problem 1 Use four decimal places in your answers for this problem. Eighteen (18) people in a department of 162 are fully trained in CPR and AED. A person shows signs of a heart attack. Five (5) people respond. What is the probability that NO (0) person who responded is trained to treat the victim? (Show all of your calcu

Random Sampling Questions

1. A random sample of 10 observations is selected from the first normal population and 8 from the second normal population. For a one-tailed test of hypothesis (.01 significance level) to determine if there is a difference in the population means, the degrees of freedom are A.18 B.17 C.16 D.None of the above 2. A random

Null Hypothesis/ One Tailed Test

Problem (One tailed test) A rental agent claims that the mean monthly rent, mu, for apartments on the east side of town is less than $725. A random sample of 13 monthly rents for apartments on the east side has a mean of $724, with a standard deviation of $15. If we assume that the monthly rents for apartments on the east sid

Null Hypothesis/ Two Tailed Test

Problem (two tailed test) A manufacturer claims that the mean lifetime, mu, of its light bulbs is 44 months. The standard deviation of these lifetimes is 7 months. Seventy bulbs are selected at random, and their mean lifetime is found to be 43 months. Can we conclude, at the 0.1 level of significance, that the mean lifetime o

Null Hypothesis

Problem (Null Hypothesis) A union of restaurant and foodservice workers would like to estimate this year's mean hourly wage, mu, of foodservice workers in the U.S. Last year's mean hourly wage was $8.16, and there is reason to believe that this year's value is different from last year's. The union decides to do a statistica

Global test for a hypothetical company

See attached file for full problem description. Where appropriate, always use an alpha of .05, always use the one tail test, always use a confidence interval of 95%, and assume Z = 1.96 in formulas for confidence interval calculations and sample size calculations. The above table represents a random sample of 16 chemical

Five Step Hypothesis Test for a Mortgage Rate

A recent article in the Wall Street Journal reported that the 30-year mortgage rate is now less than 6 percent. A sample of eight small banks in the Midwest revealed the following 30- year rates (in percent): 4.8 5.3 6.5 4.8 6.1 5.8 6.2 5.6 At the .01 significance level, can we conclude that the 30-year mortgage rate for s

Hypothesis testing

A machine is set to fill a bottle with 9 grams of medicine. A sample of 8 recently filled bottles revealed the following grams of medicine: 9.2, 8.7, 8.9, 8.4, 8.3, 8.5. Using a One Sample t Test, answer the following questions. This is what I have so far. N=6 Df = n-1 (6-1=5) T critical = 2.015 ( ) Mean = 8