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Chi-Squared Test

Chi square test of independence and goodness of fit

The Facts: Each year, the National Highway Traffic Safety Administration (NHTSA) with the National Center for Statistics and Analysis (NCSA) publishes Traffic Safety Facts, which summarizes the motor vehicle traffic crashes for the United States. Traffic Safety Facts 2005 includes trend data, crash data, vehicle data, and peop

Chi-square statistics and contingency tables

a) Why do you use the chi-square statistic? b) What type of data is used with chi square analysis? c) What are the hypotheses in a chi-square test for independence? d) How do we calculate the expected frequencies for each cell of a contingency table? e) How do we calculate the degrees of freedom for an r x c contingency

Five Step Procedure: Chi-Square Test

15.18 Sixty-four students in an introductory college economics class were asked how many credits they had earned in college, and how certain they were about their choice of major. Research question: At α = .01, is the degree of certainty independent of credits earned? Show all five steps of hypothesis testing. Credits Earn

Internet Age Group

Where people turn for news is different for various age groups. A study indicated where different age groups primarily get their news: (See Attachment).

Research in Education: Practice Problems

Create excel chart using data a. Calculate all measures of central tendency for data that are interval or ratio in measurement b. Calculate the standard deviation for data that are interval or ratio in measurement c. Assume this is a sample of students, calculate a t-test that compares boys and girls on the number of absenc

Testing Claims

Testing Claims (a) write the claim mathematically and identify Ho and Ha, (b) find the critical value(s) and identify the rejection region(s), (c) use the x square- test to find the standardized test statistic, (d) decide whether to reject or fail to reject the null hypothesis, and (e) interpret the decision in the context o

Chi-Square Test for Independence-Favourite Brand of Cola

Can people really identify their favorite brand of cola? Volunteer tasted coca-cola classic, Pepsi, Diet coke, and Diet Pepsi, with the results shown below. Research question: At a = .05, is the correctness of the prediction different for the two types of cola drinkers? Could you identify your favorite brand in this kind of test

Statistics: Chi-Square Distribution

A) Suppose that X 2nd power follows a chi-square distribution with 11 degrees of freedom. Compute P(x 2nd power lesser than or equal to 8). Round your answer to at least three decimal places. b) Suppose again that X 2nd power follows a chi-square distribution with 11 degrees of freedom. Find k such that P(X 2nd power greater

Test Statistic and Critical Value

1. H0: Σ 2 <= 22 Ha: Σ 2 > 22 A sample of 29 ages from a normal population yields a sample variance of 32.9. You want to test the following hypothesis using &#945;=.025 What is the test statistic? What is the critical value? 2. H0: Σ 2 >= 24 Ha: Σ 2 < 24 A sample of 28 ages from a normal popula

Correlation: Chi Square Test for Goodness of Fit

Suppose we wanted to look at the frequencies at which children present with certain psycho-pathologies. We obtain the following data on 50 children at a treatment facility: Depressive Disorders ADHD Anxiety Psychotic Disorders Eating Disorders 14 8 15 5 8 a. What is the n

Chi-square test and number of breakdowns

A company operates four machines during three shifts each day. From production records, the data in the table below were collected. At the .05 level of significance test to determine if the number of breakdowns is independent of the shift. Machine Shift A B C D 1 41 20 12 16 2 31 11 9 14 3 15 17 16 10

Chi Square Distribution for Two Independent Variables

1. When and how do you use a chi-square distribution to test if two variables are independent? Also, provide an example from your filed showing how you might use a contingency table for expected frequencies in your work. 2. How do you use the chi-square distribution to test if a frequency distribution fits a claimed distrib

Business Abuse

Computer abuse by employees is an ongoing worry to businesses. A study revealed the data shown in the chart below. Research Question: At a = .01, is the frequency of disciplinary action independent of the abuser's level of privilege? Computer Abuse Incident Cross Tabulated by Punishment and Privelege DATA CHART: Leve

Probabilities and statistics in insurance

3. An insurance company has two divisions, auto and property. Total annual claims, X, in the auto division follow a normal distribution with mean 10 and standard deviation 3. Total annual claims, Y, in the property division follow a normal distribution with mean 12 and standard deviation 4. Assuming that X and Y are independent,

Data Analysis in SPSS for Attitudes on Cosmetic Surgery

See the attached file. I have carried out research on the attitude of people from various countries towards Cosmetic Surgery. I surveyed about 104 people. All of them are current students or faculty at the University UK. These are the requirements: 1) Analysis: The analysis of the data looking for relationships and dif

Hypothesis Testing & ANOVA - Real World Example

1. After reading about how the ANOVA is used, and the value many researchers place on it, describe a situation, preferably from your work place, where this style of testing would be or could have been appropriate. 2. The Chi-square procedure has many uses in our daily living. Look around your organization or in your comm

Probability Distributions - Gamma and Chi Square

The attached deals with gamma and chi-square. If 15 observations are taken independently from a chi-square distribution with four degrees of freedom, find the probability that at most 3 of the 15 observations exceed 7.779. If 10 observations are taken independently from a chi-square distribution with 19 degrees of freedom,

Chi-Squared Test: Example Problems

I need to modify the data set to show If the time of month has any correlation to the amount of days people are absent. You can skew the numbers one way or another but I need a completed data set. The data set will be used for: - Calculate coefficient of correlation and coefficient of determination. - Develop a single linear

When to use Chi-Square Distribution

When and how do you use a chi-square distribution to test if two variables are independent? Also, provide an example showing how to use the contingency table to find expected frequencies.

Chi-Square and Hypothesis Testing

A) When will you use a Goodness-of-fit Chi-Square distribution? b) What are the characteristics of chi-square distribution? c) Do you have to follow the five step process of hypothesis testing? d) What are the drawbacks of chi-square testing?

Accept or Reject Null Hypothesis and Chi Square

We want to calculate a chi-square statistic and compare it with the critical value to determine whether or not GPA is significantly related to another of the factors being studied (so as not to completely discount the survey data). They chose to examine the relationship between the GPA of students and

Hypothesis Testing Chi Square Test Statistic

Assume that a 2005 poll of 1000 American voters found that 76% of Republicans favored ending the tax on dividend income, as did 42% of Democrats and 54% of Independents. Also assume that Republicans comprise 45% of American voters, Democrats 45% and Independents 10%. a.What percentage of American voters are in favor of endin

Chi square test in SPSS

Interpret the following SPSS computer output for the chi-square test. Variable COMMUTE is "How did you get to work last week?" Variable GENDER is "Are you male or female?" GENDER

Statistical Testing: Chi square test

A personnel manager has a computer-generated list of all employees that indicates that 70 percent are full-time employees, 20 percent are part-time employees, and 10 percent are furloughed or laid-off employees. A sample of 50 employees from the list indicates 40 full-time employees, 6 part-time employees, and 4 furloughed/laid-

Chi-Square Test

Collapse the response categories in the following table so that it meets the assumption of the chi-square test; then perform the test. OWNERSHIP Education Owners Non-owners Less than grade 8

Chi-Square Test

Perform a chi-square test on the following data: (a) Regulation is the best way to ensure a safe workplace. Managers Blue-Collar Workers Agree 58 66 Disagree

Chi square testing problem

12.67 The sales representative performed an experiment to test whether sending the complete program tapes for review by customers would increase sales. They selected 80 customers from the mailing list and randomly assigned 40 to receive the sample tapes and 40 to receive the full-program tapes for review. They then determine