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Hypothesis Testing


Question 1 The SAT scores of entering freshmen at X University have a normal distribution with mean μ1 = 1200 and standard deviation σ1 = 90, while the SAT scores of entering freshmen at Y University have a normal distribution with mean μ2 = 1215 and standard deviation σ2 = 110. Independent random samples

Statistical Inference

1) Find the expected values of the following probabilities...... 2) In a population of test scores not known to be probability distributions.... 5) Using the sample limit theorem...... 8) The null hypothesis that --- equals 75 for a sample of 25 subjects.... 9) Test the null hypothesis that ---- equals 50 for a sampl

Two Sample Hypothesis Testing: Is unemployment related to imports/exports?

Need a comparison between unemployment and import export data for the four different countries (China, Chile, Canada, and United States). Using the dataset attached (AISE CIA Global Demographics) and reviewing the tabs in the excel document. Use the five step hypothesis testing procedure. I am writing a paper that states

Mixed Stats

For each of the following scores, use the one-tail five percent (5%) criteria and determine if the occurrence of the score would be considered relatively likely or unlikely? a. 18 b. 24 c. 25 7. For a two-tailed test or nondirectional hypothesis, the researcher is interested in results that occur in either tail of the nor

Statistics Project Using Microsoft Excel

Read the attached case study and complete the following: 1. Prepare a report exploring the data your team collected for the management of SJGR. This report should contain the results of the various data exploratory data analyses tools such as scatter charts, histograms, correlation coefficients, etc. and the interpretation of

One-sided Test

We analyze whether the true mean discharge of wastewater per hour from an industrial plant exceeds the company claims of 1000 gallons. For the decision in the one-sided test using a=0.05: A) If the plant is not exceeding the limit, but actually the M=1000, there is only 5% chance that we will conclude that they are exceeding

Significant Difference in Average Age of Instructors

A researcher wants to investigate whether there is a significant difference in the average age of instructors, assistant professors, associate professors and full professors at a university. The faculty was selected at random and their ages were recorded. Use the collected data to complete the ANOVA chart given below. See att

Hypothesis testing problems

1.A researcher collects infant mortality data from a random sample of villages in a certain country. It is claimed that the average death rate in this country is the same as that of a neighboring country, which is known to be 17 deaths per 1000 live births. To test this claim using a test of hypotheses, what should the null and

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

At the 0.05 significance level, perform a statistical test to see the two systems are significantly different. What is the sample proportion of real estate employees who passed the exam on their first attempt? What is the sample proportion of unemployed college graduates who passed the exam on their first attempt?

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

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.

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


A random sample of 51 observations was selected from a normally distributed population. The sample mean was 88.6, and the sample variance was 38.2. Does the sample show sufficient reason to conclude that the population standard deviation is not equal to 8 at the 0.05 level of significance? Use the p-value method.

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

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

Descriptive Statistics (Hypothesis Testing)

1) Finding Critical Values: Find the critical z values. Assume that the normal distribution applies. a = 0.10; H1 is p ≠ 2) Identifying Type I and Type II Errors: Identify the type I and type II error that correspond to the given hypothesis. The proportion of M&Ms that are blue is equal to 0.10

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

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