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Hypothesis Testing

Critical value to reject the null hypothesis

Dr. Easy saw the scores from the MA-222 test and used the occasion to test the old adage that girls are smarter than boys on subjects tested by ACT. Assume the degrees of freedom for this problem is 28. Dr. Easy did the arithmetic and found the value of the test statistic was 2.69 (alpha equals .05). What is the critical value (

P-value Stat Question

In a test of hypothesis, the null hypothesis is that the population mean is equal to 60 and the alternative hypothesis is that the population mean is not equal to 60. A sample of 36 elements selected from this population produced a mean of 63 and a standard deviation of 6.3. What is the approximate p-value for this test?

Hypothesis testing: chi square and z-stat. At the .05 level of significance, test the claim that at least half of all voters prefer the democratic candidate. Test the claim that the proportion with the lawn mowers is higher than 65%. Use a .01 significance level to test the claim that for men without college degrees in that town, incomes have a higher standard deviation when a random sample of 22 men resulted in incomes with a standard deviation of 925$

1. A poll of 1,068 Americans reveals that 48% of the voters surveyed prefer the Democratic candidate for president. At the .05 level of significance, test the claim that at least half of all voters prefer the democratic candidate. 2. A nationwide study of American homeowners revealed that 65% have one or more lawn mowers. A l

9 Introductory Statistic Problems

I need help with these nine stat. questions. They come in two labs. Lab 6 and 7 and you need to use the data in the excel. I need to use the top half of the lab to answer the questions for the bottom half of the lab. Thank You ------------------------------------------------------------------------ The goal of this l

At the banks: Single waiting line versus Multiple waiting lines

The listed values are waiting times (in minutes) of customers. Bank A (Single waiting line) 6.5, 6.6, 6.7, 6.8, 7.1, 7.3, 7.4, 7.7, 7.7, 7.7 Mean=7.15 Bank B (Multiple waiting lines) 4.2, 5.4, 5.8, 6.2, 6.7, 7.7, 7.7, 8.5, 9.3, 10.0 Mean=7.15 Questions: 1). Bank A customer will receive service within how many min

Finding a test statictic and the rejection region

How many Kleenex should the kimberly Clark Corporation package of tissues contain? Researchers determined that 60 tissues is the average number of tissues used during a cold. Suppose a random sample of 100 Kleenex users yielded the following data on the number of tissues used during a cold: X-bar = 52, s = 22. Using the sampl

Simple Analysis using Minitab

I need the analysis in Minitab and the same analysis in MS WORD, I do not have minitab on my comp here that is why I am having a problem. So give everything in word too. I will see the minitab file once i go to school. A data shows how many hours of south park do fisheries and wildlife student watch per week and then further

T-test: earnings per share for major companies

StreetInsider.com reported 2002 earnings per share data for a sample of major companies (Feb. 12, 2003) Prior to 2002, financial analysts predicted the 2002 earnings per share for these same companies (Barron's Sep. 10, 2001) Use the following data to comment on differences between actual and estimated earnings per share. C

Bob's Candies Case Study

Bob's Candies Bob loves making candy, especially varieties of caramel, including plain, chocolate dipped caramels and chocolate dipped caramels with pecans. Bob has received lots of compliments from his friends and neighbors, and several have encouraged him to start his own candy making business. After several days of res

Movie cost claim

Using a significance level of 0.05 I want to conduct 3 hypothesis tests using the data below. I need to state my alternative and null hypotheses and test a claim about a proportion. I would like my claim to be that over 50% of movies made cost over 1 million dollars to make. If that is not a good claim to use in order to give

Stem and leaf plot and Hypothesis testing

Here is what I need help with. You can use any of the below information to get the answers. Please use the first set of results for the first one though. I am in the military and I took a granade launcher and launched 30 rounds at a target and then measured how far from the target I was. Just so that you understand it is

Business statistics questions.

Please see attached for fully formatted questions. ================================== 12. The American Sugar Producers Association wants to estimate the mean yearly sugar consumption. A sample of 16 people reveals the mean yearly consumption to be 60 pounds with a standard deviation of 20 pounds. a. What is the value of t

Fuel Economy Cars, Lunch Break Times, Cable Strength, etc.

1.Define the term "hypothesis"; what is a hypothesis test? 2. List and describe two types of error that can occur in hypothesis testing. 3. An independent testing laboratory has been commissioned to determine the relative fuel economy of cars, light trucks, and sport utility vehicles. A random sample of 200 within each cat

Answers of two hypothesis testing problems from the book Applied Statistics in Business and Economics by David P Doane and Lori E. Seward, McGraw Hill; 1st Edition (2006)

1. Dallas, some fire trucks were painted yellow (instead of red) to heighten their visibility. During a test period, the fleet of red fire trucks made 153,348 runs and had 20 accidents, while the fleet of yellow fire trucks made 135,035 runs and had 4 accidents. At α = .01, did the yellow fire trucks have a significantly lo

Hypothesis Testing: Introductory College Economics

Sixty-four students in an introductory college economics class were asked how many credits they had earned in college, and how certain they were about their choice of major. Research question: At α = .01, is the degree of certainty independent of credits earned? Credits Earned Very Uncertain Somewhat Certain Very Certain

Savings On Textbook Using Amazon.com

Can students save money by buying their textbooks at Amazon.com? To investigate this possibility, a random sample of 15 textbooks used during the Spring 2007 semester at Iowa State was selected. The prices for these textbooks at both Iowa State bookstore and through Amazon.com were recorded. The prices for the textbooks, inclu

Finding statistic, critical value and p value: Example problem

Suppose a study is constructed to test a claim, at a 0.05 significance level that a population proportion is 40%. A simple random sample of 750 subjects has a proportion of 42%. Determine the test statistic, critical value z = + or -, determine the p value.

Supermarket Display Effect on Sales

Does the type of display used in a supermarket affect the sales of products? As the regional sales manager for Aldi's Foods, you are interested in comparing the sales volume of Aldi's cola when the soft drink is displayed in the normal shelf location as compared to an end aisle promotional display. to test the effectiveness of t

Single-Family Home Appraisals In Two Communities

A real estate agency wants to estimate the difference in the appraised values of single-family homes in two communities. A sample of 60 listings in Strongsville and 99 listings in Brunswick yields the following results (in thousands of dollars). Strongsville, Ohio: sample mean (1)= 191.33 Brunswick, Ohio: sample mean (2)=

Determine is males who quit exercising gain weight

A study was performed to determine if males who quit exercising gain weight. Eight male adults were weighed before they stopped exercising. They were weighed five weeks after they stopped exercising. Is there sufficient evidence at alpha = 0.05 that the males who quit exercising gain weight? Subject 1 2 3 4 5

Hypothesis test for height of college hockey players

How tall are college hockey players? The average height has been 68.3 inches. A random sample of 14 hockey players gave a mean height of 69.1 inches. We may assume that x has a normal distribution with σ = 0.9 inch. Does this indicate that the population mean height is different from 68.3 inches? Use 5% level of significan

Hypothesis Testing the Effect of VS on Grades

1. You are interested in the effect of how the age of students VS affects their grades in college. To test the effect you setup a study to analyze the affect that a student's age has on their grades in college. You divide the students into groups and record their overall GPA in college. The results follow: Source of Variatio

Construct hypothesis tests in Excel for employee's

Use alpha = 0.05 unless specified otherwise. For each hypothesis test state HA (the research hypothesis) and H0 (the null hypothesis) using the proper symbols. (You can type mu or sigma for the corresponding symbols.) Include a "summary statement" for each hypothesis test. A formal Summary Statement is REQUIRED as part of al

Steel Cable Breaking Strength Statistical Analysis

Use alpha = 0.05 unless specified otherwise. For each hypothesis test state HA (the research hypothesis) and H0 (the null hypothesis) using the proper symbols. (You can type mu or sigma for the corresponding symbols.) Include a "summary statement" for each hypothesis test. A formal Summary Statement is REQUIRED as part of al

Null Hypothesis of Banks Catering to Clientele

The manager of a local branch of a bank believes that over the past few years the bank has begun to cater to a different clientele and that the average amount withdrawn from its ATMs is no longer $140.00. State the null hypothesis Ho and the alternative hypothesis H1.

Statistics - Hypothesis Testing and ANOVA

The following data represent samples of size 45 which were drawn randomly from the graduating classes of three competing high schools ... Construct a 98% confidence interval for the population mean SAT of the of students from High School 1. Test the appropriate hypothesis to examine if High Schools 1 and

Hypothesis Test: Population Mean

Suppose that 9 observations are drawn from a normal population whose standard deviation is 2. The observations are: 15, 9, 13, 11, 8, 12, 11, 7, and 10. At 95% confidence, you want to determine whether the mean of the population from which this sample was taken is significantly different from 10. Compute the value of the tes

Inferential Statistics for different techniques of relaxation

The solution addresses: Three different relaxation techniques are given to randomly selected patients in an effort to reduce their stress levels. A special instrument has been designed to measure the percentage of stress reduction in each person. The data is shown below. You can assume normality and that good randomization an

Level of Significance for Z and T Tests

The solution addresses the following. A new weight-watching company advertises that those who join will lose, on average, 10 lbs. the first two weeks. A random sample of 50 people who joined revealed the mean loss to be 9 lbs. with a standard deviation of 2.8 lbs. At the .05 level of significance, can we conclude that those

Independent Samples hypothesis test for Effects of Alcohol

Confidence Interval for Effects of Alcohol: An experiment was conducted to test the effects of alcohol. The errors were recorded in a test of visual and motor skills for a treatment group of people who drank ethanol and another group given a placebo. The results are shown in the accompanying table (based on data from "Effects of