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Student's t-Test

T test for comparing IQ of males and females

Calculate and compare the means for IQ as a dependent variable and gender as your independent variable. Do you think males and females differed in their IQ scores? Why? Male mean= 99.33 N= 55 Std Dev= 13.192 Range= 62 Kurtosis=.224 Skewness=.451 Female Mean=101.82 N=33 Std Dev=12.677 Range=45 Kurtosis=-.731

The difference between t-tests and z-tests

In drawing an inference using a single mean in hypothesis testing, you often have a choice between doing a z-test or a t-test. Many researchers will always choose to do the t-test even under circumstances where the z-test would work as well. Explain why the t-test was developed and why it is preferred.

Statistics: AIU survey responses; two-tailed hypothesis test, t-test, z-test,

See attached data file. Using AIU's survey responses from the AIU data set, complete the following requirements in the form of a report: Perform a two-tailed hypothesis test on both the intrinsic and the extrinsic variable's data, using a .05 significance level. Begin by creating a null and an alternate statement. Use Mic

Hypothesis test for the population mean:T-test

A rental agent claims that the mean monthly rent, , for apartments on the east side of town is less than $675 . A random sample of 18 monthly rents for apartments on the east side has a mean of $661, with a standard deviation of $24 . If we assume that the monthly rents for apartments on the east side are normally distributed, i

Statistics Problem

Question 8. A sample of scores on an examination given to both makes and females in MAT 500 is: Males 72, 69, 98, 66, 85, 76, 79, 80, and 77 Females 81, 67, 90, 78, 81, 80, and 76 At the .01 level of significance, is the mean grade of the female students higher than that of the males?

Independent Sample t test nonnumerical data

I am having a hard time understanding how to perform t-tests in nonnumerical data. A. Perform two t - tests to determine if there is a difference in your spending category based on Card Type or Reward Type. Do people who get World Points spend more than those who get Gas Rebates on your Spend type? Do people with Master

Independent Sample t test credit cards

Using the credit card data that appears on the next tab, analyze Airline Spend. Perform two t-tests to determine if there is a difference in your spending category based on Card Type or Reward Type. Do people who get World Points spend more than those who get Gas Rebates on your Spend type? Do people with Master Cards spend

Interpretation of Descriptive Statistics: Nurse Example

An insurance company is trying to determine if there is a significant difference in the average number of sick days that registered nurses and nurse practitioners use per year. The data analysis provided the following output. Two sample T for registered nurses vs nurse practitioners: N

Independent sample t test: Times required by sprinters

Two groups of ten sprinters run 100 meters. The times required by sprinters in the first group are as follows: 13.7 14.2 13.2 11.3 12.6 10.0 10.1 14.1 13.8 13.2 The times required by sprinters in the second group are as follows: 17.3 10.6 14.0 15.9 15.1 13.4 18.9 17.2 17.6 10.1 Assuming that = 0.05, test


Question 3 Identify the null hypothesis, alternative hypothesis, test statistic, P-value, conclusion about the null hypothesis, and final conclusion that addresses the original claim Various temperature measurements are recorded at different times for a particular city. the mean of 20 degrees celcius is obtained for 40 tempe

Hypothesis Testing

The MBA department is concerned that dual degree students may be receiving lower grades than the regular MBA students. Two independent random samples have been selected 150 observations from population 1 (dual degree students) and 150 from population 2 (MBA students). The sample means obtained are X1(bar)=79 and X2(bar)=82. It i

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

Independent sample t test-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

Statistical Measures: Location and Variability Whitewater Trucking

Please see the attached file. You must show your work and use SPSS if applicable. The Whitewater Trucking Company delivers freight in and about Southeast Wisconsin. The number of tons of freight Whitewater Trucking Company has delivered the past 24 days is shown in the following table. a. Please summarize the data using the

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

Calculation of Test Statistic for Paired T Test

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 pa

One Sample T-Test: Mean

One eight Friday quizzes, Bob received scores of 80, 85,95,92,89,84,90,92. He tells Prof. Hardtack that he is really a 90+ performer but this sample just happened to fall below his true performance level. Using the appropriate statistical test can you say that from this data Bob does not perform at a 90 level? a. State the null

Explaining a T-Test

Attached you will see a set of variables from a control group and an experimental group. The attachment has calculations such as mean, mode, median, standard deviation etc. There were also t-tests performed. What I need help on is explaining what the results mean in a short paragraph.

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 - T-distribution

A) Consider a t distribution with 10 degrees of freedom. Compute P(t lesser than or equal to 1.36). Round your answer to at least three decimal places. P(t lesser than or equal to 1.36) = b) Consider a t distribution with 9 degrees of freedom. Find the value of c such that P(-c lesser than t lesser than c)=0.95 . Round y

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?