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Student's t-Test

The answer to Hypothesis Testing: Independent sample t test

Construct the Two Sample chart using excel, with the data provided? Chapter 11, problem 47 - The city of Laguna Beach operates two public parking lots. The one on Ocean Drive can accommodate up to 125 cars and the one on Rio Rancho can accommodate up to 130 cars. City planners are considering both increasing the size of th

Statistics: Study of perceptual illusions under two different lighting conditions

A psychologist conducts a study of perceptual illusions under two different lighting conditions. Twenty participants were each tested under both of the two different conditions. The experimenter reported: "The mean number of effective illusions was 6.72 under the bright conditions and 6.85 under the dimly lit conditions, a diffe

Independent sample t test in SPSS.

2. SPSS computation and Interpretation (T-test): Use the "2009FinalExamData1_OnlineSurveyResponses.sav" file. This data set consists of 96 MBA students' perception/attitude toward social media usage. You should find the variable definition by clicking the SPSS "Variable View" for details. A researcher (let's call this indivi

Use independent-samples, t-test procedure: smokers have greater lung damage

The purpose of the present study conducted by Eidelman et al. (1991) was to identify the nature of lung destruction in cigarette smokers before the development of marked emphysema. Three destructive index measurements were made on the lungs of lifelong nonsmokers and smokers who died suddenly outside the hospital of nonrespiato

Math Problem

Hello. I have finished all of my homework except for this one question. I need step-by-step solutions for this problem, so that I can do the other questions like this in future homework assignments. A machine is designed to fill jars with 16 ounces of coffee. A consumer suspects that the machine is not filling the jars comple

Statistics Problems

Hello. I am doing my homework assignment and I cannot figure out and understand how to solve some of the problems. I have answered the questions that I am able to, but I cannot answer the other ones no matter how hard I have tried. Can you PLEASE include step-by-step instuctions on how to solve the problems. If I get behind with

Statistics: Is a significant decrease in the absences after the fitness program?

Robyn is the Vice President for Human Resources for a large manufacturing company. In recent years she has noticed an increase in absenteeism that she thinks is related to the general health of the employees. Four years ago, in an attempt to improve the situation, she began a fitness program in which employees exercise during


Ketsia is the fitness coordinator at the local youth center. She has found a program that proports to help teens lose weight if they complete the course. A random sample of five recent participants showed that the following weights before and after completing the course. At the .05 significance level, can we conclude that the

T test for Whitner Autoplex Data Set

The null hypothesis is that the mean price paid by younger customers (µ1) will not be as high as the price paid by older customers (µ2). The alternative hypothesis is that younger customers spend more on average than their older counterparts. Do a two sample test. 1. Perform the five-step hypothesis test on the data.

Statistics: What Should the Experimenter Prove?

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

Z table

The amount of time a bank teller spends with each customer is normally distributed with a mean of 3.10 minutes and a standard deviation of 0.40 minutes. (Use the z table) If a random sample of 16 customers is selected from the bank, what is the probability that the average time spent per customer will be at least 3 minutes?

Paired t test

Mitigating barriers to black employment through affirmative action regulations: a case study Ward Thomas The review of black political economy Winter 2000 Affirmative action regulation as a public policy to mitigate racial inequality in the labor market has been under political attack in recent years. During the 1980's, th

One and two-tailed tests

Imagine that research shows the average age of people who buy lottery tickets to be 70 with a standard deviation of 12. A sample of 30 individuals from Hawaii is selected and their ages are recorded as shown below. At a = 0.05 is there enough evidence to state that the average age of ticket buyers is the same in Hawaii as it is


An Excel Spreadsheet is reprinted below. Interpret the t-test results. Are they statistically significant? t-Test: Paired Two Sample for Means Beer Soda Variable 1 Variable 2 Mean 16.83333333 15.8


The managers in a company's East and West regions were rated on the basis of the company's evaluation system. A researcher wishes to conduct a t-test of means to determine if there is a difference between the East and West regions. Perform this calculation. Region Manager Rating Region Manager

Hypotheses testing for independent sample t test.

Marks) A firm is studying the production times for two production methods. The firm is satisfied with production method A and is prepared to continue using it if the mean delivery time is the same as or less than for production method B. However, if the firm finds that the mean delivery time for method B is less than that for


Please see attached problem. -------------------------------- Ralston Enterprises has assets that will have a market value in one year as shown below: Probability 1% 6% 24% 38% 24% 6% 1% Value ($ million) 70 80 90 100 110 120 130 That is, there is a 1% chance the assets will be worth $70 million, a 6% chance the assets

Test to see if the mean of the population is at least 12 ounces.

From a population of cereal boxes marked "12 ounces," a sample of 16 boxes is selected and the contents of each box weighed. The sample revealed a mean of 11.7 ounces with a standard deviation of 0.8. Test to see if the mean of the population is at least 12 ounces. Use a 0.05 level of significance. (may use traditional or p-

Intro to t Test is given.

Evolutionary theories often emphasize that humans have adapted to their physical environment. One such theory hypothesizes that people should spontaneously follow a 24-hour cycle of sleeping and waking-even if they are not exposed to the usual pattern of sunlight. To test this notion, eight paid volunteers were placed (individua

T-Test on Adaption to Physical Environment

Evolutionary theories often emphases that humans have adapted to their physical environment. One such theory hypothesizes that people should spontaneously follow a 24-hour cycle of sleeping and waking - even if they are not exposed to the usual pattern of sunlight. To test this notion, eight paid volunteers were placed (indivi

Independent sample t test for comparing means.

Consider the following results for two samples randomly taken from two populations. Sample A Sample B Sample Size 150 150 Sample Mean 412 405 Sample Std Deviation 128 54 A. At a .01 level of significance, test whether the

T test for employee absenteeism

The mean (m) number of employee absences in company X is 6 days annually, according to previous studies conducted by the Human Resources Department. Five years have passed without determining whether this mean continues to be the same. Therefore, the company's industrial psychologist selects a sample of 9 employees and deter

T- Test of a Multiple Regression Model

Using 19 observations on each variable, a computer program generated the following multiple regression model: y = 43.7 - 1.83x_1 - 4.25x_2 If the standard errors of the coefficients of the independent variables are, respectively, 1.24 and 2.04, can you conclude that the independent variable is needed in the regression m

Independent sample t test

Two new york designs are under consideration for possible adoption in an assembly plant. A time study is conducted with 10 workers using design 1, and 12 workers using design 2. The means and standard deviation of their assembly times in minutes are below. Design 1 Design 2 Mean 78.3 minute

T- Test for Matched Groups

1. Outline the difference between the t test for independent groups and the t test for matched groups. 2. A researcher computed the F ratio for a four-group experiment.The computed F is 4.86. The degrees of freedom are 3 for the numerator and 16 for the denominator. a. Is the computed value of f significant at p <.05? Exp

Null and Alternate hypothesis

Past records suggest that the mean annual income,m1 , of teachers in state of Connecticut is less than or equal to the mean annual income,m2 , of teachers in California. In a current study, a random sample of 25 teachers from Connecticut and an independent random sample of 25 teachers from California have been asked to report t