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Hypothesis Testing

Difference between one-tailed and two-tailed tests

1. What is the difference between one-tail and two-tail test? Explain by using your own example. 2) SUPPOSE BABSIE GENERATED THE FOLLOWING PROBABILITY DISTRIBUTION X P(X) 5 0.25 7 0.3 10 0.25 12 0.05 15 0.15 A) Is this probability distribution discrete or continuous? Explain your reasoning. B) Calculate the e

One Sample Hypothesis Testing and Data Processing

Describe the results of a hypothesis test of one population mean or population proportion. Be sure to include the following in your answer: 1. Formulate both a numerical and verbal hypothesis statement regarding your research issue. 2. Perform the five-step hypothesis test on data pertaining to your selection. Step 1:

Statistics: Cash Withdrawal Analysis

Cash withdrawals (in multiples of $20) at an on-campus ATM for a random sample of 30 Fridays and 30 Mondays are shown below. At alpha = .01, is there a difference in the mean ATM withdrawal on Monday and Friday? (a) Make stacked dot plots of the data (a sketch is OK). (b) State the hypotheses. (c) State the decision rule a

The Independence of Noise Level

High levels of cockpit noise in an aircraft can damage the hearing of pilots who are exposed to this hazard for many hours. A Boeing 727 co-pilot collected 61 noise observations using a handheld sound meter. Noise level is defined as "Low" (under 88 decibels), "Medium" (88 to 91 decibels), or "High" (92 decibels or more). There


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

Two or More Sample Hypothesis Tess

Using numerical data from one of the 2005 Real Estate data set, develop one business research question (The research question is "Is an Average size house is 2000 square feet?") from which you will formulate a research hypothesis that will test two or more populations. Prepare a paper describing the results of a hypothesis t

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

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

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

Significance Level of Entrances Used

There are four entrances to the Government Center Building in downtown Philadelphia. The building maintenance supervisor would like to know if the entrances are equally utilized. To investigate, 400 people were observed entering the building. The number using each entrance is reported below.

Significance Level Solution Set

Exercise 23 A real estate agent in the coastal area of Georgia wants to compare the variation in the selling price of homes on the oceanfront with those one to three blocks from the ocean. A sample of 21 oceanfront homes sold within the last year revealed the standard deviation of the selling prices was $45,600. A sample of 18

Sample and Significance Level

The president of the American Insurance Institute wants to compare the yearly costs of auto insurance offered by two leading companies. He selects a sample of 15 families, some with only a single insured driver, others with several teenage drivers, and pays each family a stipend to contact the two companies and ask for a price q

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