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Hypothesis Testing

Z Test and ANOVA

1. An Ivy League college is concerned that out of state students may be receiving lower grades than the state residents students. Two independent random samples have been selected: 165 observations from population 1 (Out of state students) and 177 from population 2 (State students). The sample means obtained are X1(bar)=86 and X

Performing a 5-step hypothesis testing

Do students at various universities differ in how sociable they are? Twenty-five students were randomly selected from each of three universities in a region and were asked to report on the amount of time they spent socializing each day with other students. The result for University X was a mean of 5 hours and an estimated popula

Conducting a 5-Step Hypothesis Testing

Twenty students randomly assigned to an experimental group receive an instructional program; 30 in a control group do not. After 6 months, both groups are tested on their knowledge. The experimental group has a mean of 38 on the test (with an estimated population standard deviation of 3); the control group has a mean of 35 (with

Rocky University: How prevalent is Cheating?

Note: The attached Excel file provides the data required for this question. During the global recession of 2008 and 2009, there were many accusations of unethical behavior by Wall Street executives, financial managers, and other corporate officers. At that time, an article appeared that suggested that part of the reason for

Example of one sample t-test

A share tipping service claims that its selections give an average return of 10% if held for 12 months. An investor wants to investigate this claim and records the returns of the last 20 shares that have met the 12 month period. The sample mean return is 9% and the standard deviation is 2.5%. You can assume that the return from

Hypothesis testing for means - t scores

I don't understand the formulas and rationales for the attached. I also don't have the correct version of excel to use the tool pack I need so I am doing everything manually. I am doing the work on my own but want to make sure it is somewhat correct prior to turning in. Any help would be appreciated. Thank you.

Death Penalty as Moral Acceptance

In 2010, 65% of adult Americans thought that the death penalty was morally acceptable. In a poll conducted by the Gallup Organization, a simple random sample of 1005 adult Americans resulted in 704 respondents stating that they believe the death penalty was morally acceptable when asked, "Do you believe the death penalty is mora

Solving various questions on hypothesis testing

______ 1. The variable about which the investigator wishes to make predictions or estimates is called the ____. a. dependent variable b. unit of association c. independent variable d. discrete variable ______ 2. In regression analysis, the quantity that g

T-test hypothesis

We have been working with one-sided and two-sided t tests but I do not know how to do this problem: The observed time that 20 individuals spend standing and walking per day is reported in the following table: Group n Mean Std. dev Group 1 (lean) 10 525.751

Calculating the cramer's and lambda using chi-square

Construct a cross tabulation to examine the relationships between the two nominal/ordinal level variables. Assume that you selected a random sample of two hundreds cases and collected data on these cases. Calculate Chi Square ans as appropriate, Lambda, gamma and Cramer's V. Briefly state conclusion about hypothesis relationship

Cross tabulation and analyzing relationships among variables

Do women and men have different opinions about affirmative action? Based on a sub sample of 2008 GSS, the output figure below shows respondent's sex (sex) and attitudes toward affirmative action (DISCAFF: Are whites hurt by affirmative action). Whites hurt by Affirmative action* respo

Analysis of Liberals & Conservatives with Hypothesis Test

From the 2008 GSS-the average educational attainment for liberals is 13.90 year Sy=3.27) and the average educational attainment for conservatives is 13.55 years (Sy=2.82). Data are base on 187 liberals and 227 conservatives responses. a. Test research hypotheses that there is a difference in level of education between liberals

Discussing a Paired T-Test for Two Depenedent Samples

Write ideas for a hypothesis that you might test to compare two or more samples in your example. Indicate which hypothesis test you would use and the samples you would select. To support your choice of test include a brief discussion of the level of measurement, the number of samples involved, and whether the samples are related

Defining the hypothesis tests

1) a) Which variable in an experiment determines whether to use parametric or nonparametric procedures? b) In terms of the dependent variable, what are the two categories into which all nonparametric procedures can be grouped? 2) a) Why, if possible, should we design a study that meets the assumptions of a parametric proc

Hypothesis Testing and Population Analysis

I would like the response to the questions below in excel format, so that I can see the formulas used. 1. In a recent year, the FCC reported that the mean wait for repairs for AT&T customers was 25.3 hours. In an effort to improve this service, suppose that a new repair service process was developed. This new process when use

The solution gives detailed steps on performing a hypothesis testing (5 step procedure). All the formula and calcuations are shown and explained. An excel output is also included.

A consumer magazine randomly selected 100 new hybrid car dealers from across the country, and created a list of retail prices. They want to know if the price differs from $25,000. RQ: Is the average hybrid car dealer retail price different than $25,000 with a 95% confidence level? Use Alpha = .05 A. Choose the Hypothesis H1:

Six Sigma Tools for Testing Statistical Significance

"Suppose you want to know if a new design of a product is actually better than the current product. For example, your design team is working on increasing the speed of the KX Speed Drill. You have produced a small batch of the new design, the KX2, and you want to know if this speed is faster than the current speed of 17.5 revs p

Designing a Hypothesis Test

How do you design a test pilot and what would it look like once finished? The situation I have involves a local clinical practice for individuals who show signs of depression. The doctor has noticed that some of her clients do better when they participate in group interventions, and others make more progress when she sees them

Testing the Null Hypothesis and Interpreting the P-Value

Southside Hospital in Bay Shore, New York, commonly conducts stress tests to study the heart muscle after a person has a heart attack. Members of the diagnostic imaging department conducted a quality improvement project with the objective of reducing the turnaround time for stress tests. Turnaround time is defined as the ti

Various Hypothesis Testing Problems

Diabetes The insulin pump is a device that delivers insulin to a diabetic patient at regular intervals. It presumably regulates insulin better than standard injections. However, data to establish this point are few, especially in children. The following study was set up to assess the effect of use of the insulin pump on HgbA

The solution gives detailed steps on performing a chi-square test for checking independence for multiple groups. Also, another chi-square test using expected frequency technique is shown and explained.

I need to know which equation to use and detailed steps to answer the following question by hand. The following data were collected in a clinical trial evaluating a new compound designed to improve wound healing in trauma patients. The new compound is compared against a placebo. After treatment for 5 days with the new comp

Hypothesis Testing for Two Samples

I need help solving the following problems: In this problem set you will get some practice performing hypothesis tests for two samples. If you use Statdisk to perform any portion of these analyses, please include the results, label them, and refer to them accordingly in your interpretations. Good luck and enjoy! 1. Ten

Statistics Practice Problems

1) The health of employees is monitored by periodically weighing them in. A sample of 54 employees has a mean weight of 183.9 lb. Assuming that σ is known to be 121.2 lb, use a 0.10 significance level to test the claim that the population mean of all such employees weights is less than 200 lb. Identify the null hypothesis, alt

Hypothesis Testing for a Single Mean: Fat Content of Hamburgers

See the attached file. 1. The fat content was determined for 40 hamburgers sold by a fast food restaurant. The results in grams appear below. 20.0 18.7 21.6 20.9 21.8 20.2 19.7 18.9 19.5 21.5 19.3 21.2 18.4 21.0 21.6 20.6 20.7 21.9 20.1 17.1 18.1 21.1 19.3 21.5 20.1 16.5 18.9 17.4 20.8 18.5 21

Average salary of blue-collar workers

While negotiating a labor contract, the president of a company argues that the mean annual earnings of blue-collar workers is less than $56,000. The labor union argues that the salary is more than $56,000. A random sample of the annual earnings of 350 blue-collar workers is taken and contained in the file LaborDispute.xls.


Webcredible, a UK-based consulting firm specializing in websites, intranets, mobile devices, and applications, conducted a survey of 1,132 mobile phone users between February and April 2009. The survey found that 52% of mobile phone users are now using the mobile Internet. (Data extracted from "Email and Social Networking Most P

Test a claim and STATDISK

(1) Assume that head injury measurements are not affect by an interaction between type of car (foreign, domestic) and size of car (small, medium, large). Is there sufficient evidence to support the claim that size of the car has an effect on head injury measurements? Use display 1 which results from the head injury measurem

The solution gives detailed steps of hypothesis testing on mean difference using the example of market research firm. All formula and calculations are shown. Finally, conclusion is stated clearly.

P 21 A market research firm used a sample of individuals to SELFIII rate the purchase potential of a particular product before and after the individuals saw a new television commercial about the product. The purchase potential ratings were based on a 0 to 10 scale, with higher values indicating a higher purchase potential. T