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Hypothesis Testing

Hypothesis, P=values and rejection of null

Same sex marriages was legalized across Canada by the Civil Marriage Act enacted in 2005. Is this supported by the majority, or a minority, of the Canadian population. A poll conducted for the Globe and Mail newspapers in July 2005 of 1000 Canadians asked whether this bill should should stand or be repealed. The response were 55

SPSS - t-test, W test, and Levene's test - Simple data

Instructions In this project, examine if the two independent groups of participants obtained significantly different scores on the dependent variable in the data set. Additionally, examine the normality of distribution of scores, and the homogeneity of variance across the two independent groups. (1) Calculate a t-test for

Perform hypothesis testing on one variable's data

Perform hypothesis testing on one variable's data. (Choose either the intrinsic or extrinsic column.) Perform a t-test by formulating a null and an alternative statement, choosing an acceptable significance value, determining the appropriate critical value, selecting the test statistic and determining its value from the sample d

Creating More Precise Experiments

A researcher has reason to be that, for an experiment with 50 points, a 95% prediction interval would be of width 4. If the researcher wishes to run a more precise experiment that will result in a 95% prediction interval of width 2, then the researcher will require: A) 200 points B) More than 200 points C) 50 po

Test of hypotheses: difference between means and proportions

1) SafeRoad Stores is redesigning the checkout lanes in its stores throughout the country. Two designs have been suggested. Tests on customer checkout times have been conducted at two stores where the two new systems have been installed. A summary of the sample data follows: System A System B Sample size

Hypothesis Testing Problems and Sample Questions

Please view the attached files. 1. Data File ERWAITING contains the waiting times in minutes for 15 randomly selected patients at a hospital main emergency room facility and at three satellite facilities. a. At the .05 level of significance, is there evidence that the mean waiting time at the main facility is more than o

Hypothesis Testing for fax cost

Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. The firm examined 35 randomly chosen fax transmissions during the next year, yielding a sample mean of 14.44 with a standard devi

Difference Amount Types of Gasoline

Martin Motors has in stock three cars of the same make and model. The president would like to compare the gas consumption of the three cars (labeled car A, car B, and car C using four different types of gasoline. For each trial, a gallon of gasoline was added to an empty tank, and the car was driven until it ran out of gas.

Regression coefficient

An estimated regression coefficient is 10 with a standard error of 5. The null hypothesis is that the partial regression coefficient equals one. What is the value of the t-statistic for testing the null hypothesis of the regression coefficient? A) 1 B) 2 C) 1.8 D) 0.5

Statistics: Frequency, Chi-Square, Mean Square, and Error

Use the following information to answer questions: A manufacturer of automobile transmissions uses three different processes. The management ordered a study of the production costs to see if there is a difference among the three processes. A summary of the findings is shown below. Process 1 Process 2 Process 3 Total Proce

Critical value, level of risk

1. (10) The CEO for the Red White and Blue T-Shirt Company expects quality garments produced with a minimum of defective garments. Further, he expects the same quality work from his employees regardless of whether they work in the day or in the evening. To test productivity quickly, he has his shift foremen record the number

Jerry's Bargain Department Store: Level of Risk

Jerry's Bargain Department Store spent $50,000 on a training program to improve sales effectiveness of its employees. Below is a table of the before and after sales amounts for a random sample of employees who took the training program. Assume that data is recorded for an equal period of "before"-"after" time. Use the 1% level f

A Knowledge about Hypothesis Test

A consumer watchdog organization wants to see whether Bank N in the northern part of a state has a higher default rate than Bank S in the southern part of that same state. Researchers for the group sample the proportion of defaults on loans at both banks. Out of 100 loans for Bank N, they find 30 have defaulted; out of 100 lo

Statistics - Null & Alternative Hypothesis - Critical Values

Identifying H0and Hr in ex 5-12 , examine the given statement , then express the null hypothesis H0 and alternative hypothesis H1 in symbolic form. 6. The mean IQ of statistics students is at least 110. 8. The percentage of men who watch golf on tv is not 70%, as is claimed by the Madison Advertising Company. Finding C

Multiple choice questions from hypothesis testing.

Many elementary school students in a school district currently have ear infections. A random sample of children in two different schools found that 16 of 42 at one school and 21 of 36 at the other had this infection. At the .05 level of significance, is there sufficient evidence to conclude that a difference exists between the

Difference Between Testing a Single Mean or Two Means

Explain the difference between testing a single mean and testing the difference between two means. What two assumptions must be met when one is using z test to test differences between two means? When can the sample standard deviations s1 and s2 be used in place of the population standard deviations σ1 and σ2 ?

Hypothesis Testing, Significance Levels, Critical Values and Decision Rule

Please see the attached file for the fully formatted problems. Faced with rising fax costs, a firm issued a guideline that transmissions of 10 pages or more should be sent by 2-day mail instead. Exceptions are allowed, but they want the average to be 10 or below. The firm examined 35 randomly chosen fax transmissions during t

1 Tailed vs 2 Tailed Test and Null vs Alternative Hypothesis

1. Explain the difference between a left-tailed, two-tailed, and right-tailed test. When would we choose a two-tailed test? How can we tell the direction of the test by looking at a pair of hypothesis? How can we tell which direction (or no direction) to make the hypothesis by looking at the problem statement (research questio

Hypothesis Development and Five Step Hypothesis Testing

The hypothesis should be developed to include an assessment of women with similar education and work experiences earn less money than men with similar qualifications. The data set and legend are included as an attachment. Please provide a five-step hypothesis test with the data relevant to the selection (data set and legend

The Significance Level and Estimate P-Value

"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 concl

Hypothesis Testing on Multiple Scenarios

Problem 1 Consider the Mission Valley Power Company (MVP), which has over 6000 customers. In response to a request from the Michigan Public Utilities Commission, MVP needs to estimate the average kilowatts of electricity used by customers on April 1. The only way to get this number is to select a random sample of customers and

Descriptive Statistics (Comparing Variation in Two Samples)

Tobacco and Alcohol Use in Animated Children's Movies: Lists times (in seconds) that animated children's movies show tobacco use and alcohol use. The 50 times of tobacco use have a mean of 57.4 sec and a standard deviation of 104.0 sec. the 50 times of alcohol use have a mean of 32.46 sec and a standard deviation of 66.3 sec.

Standard Deviation for Nielsen Media Research

PROBLEM SET II ALTERNATE 1 9-11. The owner of Britten's Egg Farm wants to estimate the mean number of eggs laid per chicken. A sample of 20 chickens shows they laid an average of 20 eggs per month with a standard deviation of 2 eggs per month. a. What is the value of the population mean? What is the best estimate of this v

Standard Deviation of Breakfast Cost

A recent survey indicated that the average amount spent for breakfast by business managers was $7.58 with a standard deviation of $0.42. It was felt that breakfasts on the West Coast were higher than $7.58. A sample of 81 business managers on the West Coast had an average breakfast cost of $7.65. At a= 0.05, what is the t

Telephone Efficiency Significance

To encourage telephone efficiency, a catalog call center issues a guideline that at least half of all telephone orders should be completed within 2 minutes. Subsequently, a random sample of 64 telephone calls showed that 40 calls lasted over 2 minutes. (a) At α = .05 is this a significant departure from the guideline in

Hypothesis testing for population proportion problems

A study by the Investment Company Institution (ICI) in 2004, which randomly surveyed 3,500 households and drew upon information from the IRS. If found that 72% of households have conducted at least one IRA rollover from a an employer sponsored retirement plan. Suppose a recent random sample of 90 households in the greater Detr

Hypothesis Testing of Genetically Modified Foods

Design (but not do) a test to see if genetically modified foods are different from non-genetically modified (NGM) foods. Assume you are designing a study that will analyze GM and NGM foods, and answer the following questions. 1. What will your null and alternative hypotheses be? (Hint: Ensure your null and alternative hypo

Nonparametric Hypothesis Test

Using the research question and data below conduct a equivalent nonparametric test of hypothesis below. The hypothesis for the ANOVA test is: H0: μ1=μ2=μ3=μ4=μ5=μ6=μ7=μ8=μ9 (all means are equal) H1: Not all means are equal (at least one is different) Telecommunication Servi