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    Chi-Squared Test

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    Evidence to Conclude Significance Tests

    One possible side effect of air pollution is genetic damage. A study designed to examine this problem exposed one group of mice to air near a steel mill and another group to air in a rural area and compared the number of mutations in each group. Here are the data for a mutation at the Hm-2 gene locus: Mutation Steel mill air

    Chi-Square Test of Independence for Gender and Type of Vehicle

    Use the given contingency table to (a) find the expected frequencies of each cell in the table, (b) perform a chi-square test for independence, and (c) comment on the relationship between the two variables. Assume the variables are independent. The contingency table shows the results of a random sample of 500 individuals class

    Sample Size & Chi-Square Questions

    1. Why do the critical values from the Chi-square distribution get larger as the degrees of freedom get larger? Recall that this is opposite the pattern for the t-table. 2. Why is choosing sample size important(with specific reference to proportions)?

    Statistics - Goodness of Fit

    Ten Experiments were done to find the effects of bonus rates paid to the sales team. What is the line of best fit through the following results? How good is the fit? %Bonus 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 Sales('00s) 3, 4, 8, 10, 15, 18, 20, 22, 27, 28

    Chi-square test: vehicle type and mall location

    15.22 A student team examined parked cars in four different suburban shopping malls. One hundred vehicles were examined in each location. At alpha =0.05, does vehicle type vary by mall location

    Chi-square test : Degree of uncertainty and credit earned

    Observed Frequencies Degree of certainty Very certain somewhat certain Very certain Total Credit earned 0-9 12 8 3 23 10-59 8 4 10 22 60 or more 1 7 11 19 Totals 21 19 24 64 Test whether the degree of uncertainty is related to the credit earned.

    Chi-square Test - Job Pressure and Age

    A study regarding the relationship between age and the amount of pressure sales personnel feel in relation to their jobs revealed the following sample information. Questions are asked of sales people and the numbers of people that are in each group is shown in the table below. Is there a relationship between job pressure and ag

    Chi square Hypothesis Testing

    Please see the attached file. The following data is taken from a customer satisfaction survey for a food product. Perform a Chi-square test to test the claim of whether a statistically significant relationship exists between the customer's satisfaction level and decision to repurchase the food item again. You may use the m

    Chi-Square Analysis of Distribution and Deviation of Any Sample

    Three samples of Drosophila heterozygous for the recessive genes black body (b) and rough eyes (r) were inbred and the following data were obtained. A. perform a chi-square analysis for each sample assuming a 9:3:3:1 distribution. B. Is there a significant deviation in any of these samples? Use the table attached.

    ChiSquare test for goodness of fit

    The author drilled a hole in a die and filled it with a lead weight, then proceeded to roll it 180 times. (Yes, the author has too much free time.) The results are given in the frequency distribution in the margin. Construct the frequency distribution for the outcomes that you would expect from a die that is perfectly fair an

    Chi-Square test for goodness of fit

    Perform a Chi-Square Goodness of Fit (GOF) test to determine whether there is a difference between the observed values versus the expected values expected. The null hypothesis should be there is no statistical difference between the expected and observed distribution, and the alternate hypothesis is that there is a statistical d

    CHi-Square test

    15.8 In a three-digit lottery, each of the three digits is supposed to have the same probability of occurrence (counting initial blanks as zeros, e.g., 32 is treated as 032). The table shows the frequency of occurrence of each digit for 90 consecutive daily three-digit drawings. (a) Make a bar chart and describe it. (b) Calculat

    Chi square test samples

    Please see attached document. 1.TABLE 11-2. Many companies use well-known celebrities as spokespersons in their TV advertisements. A study was conducted to determine whether brand awareness of female TV viewers and the gender of the spokesperson are independent. Each in a sample of 300 female TV viewers was asked to identify

    Relationship Between Gender and the Aggression Content of Dreams

    Gender differences in dream content are well documented (Winget & kramer, 1979). Suppose a researcher studies aggression content in the dreams of men and women. Each participant reports his or her most recent dreams. Each dream is judged by a panel of experts to have low,medium, or high aggression content. The observed frequenc

    Photo Modifications: Distribution of Responses and Preferences

    A researcher is investigating the physical characteristics that influence whether a person's face is judged as beautiful. The researcher selects a photograph of a women and then creates two modifications of the photo by (1) moving the eyes slightly farther apart and (2) moving the eyes slightly closer together. The original phot

    Chi square, independence and other concepts

    1. In a chi-square test, the sample data are called observed frequencies. True False 2. One advantage of the chi-square tests is that they can be used when the data are measured on a nominal scale. True False 3. A chi-square test for goodness of fit is used to evaluate a hypothesis

    Statistics problems: Chi square test

    1. A researcher is investigating the physical characteristics that influence whether a person's face is judged as beautiful. The researcher selects a photograph of a woman and then creates two modifications of the photo by (1)moving the eyes slightly farther apart and (2) moving the eyes slightly closer together. The origi

    Chi-squared Test of Goodness of Fit

    Charmers' Candy Store sells wrapped hard candies in the following flavors: strawberry, blueberry, lemon, lime, and orange. They advertise that there are equal proportions of each flavor in every size of their candy boxes. To test their claim, a parent opens her son's candy box and counts each flavor. On the next page are mom'

    Chi square statistics and ANOVA tables

    1 An investigator for a consumer cooperative organized a study of the mileages obtainable from three different brands of gasoline. Using 15 identical motors set to run at the same speed, the investigator randomly assigned each brand of gasoline to 5 of the motors. Each of the motors was then run on 10 gallons of gasoline, with

    Statistical Analysis on Classes of Childcare Workers

    A large study of child care used samples from the data tapes on the current population survey over a period of several years. The result is close to an SRS of child care workers. The current population survey has three classes of child care workers: private household, nonhousehold, and preschool teacher. Here are data on the

    Chi-square GOF test for a uniform distribution

    Ages of 56 attendees of a Harry Potter movie are shown. (a) Form seven age classes (10 to 20, 20 to 30, etc.). Tabulate the frequency of attendees in each class. (b) Calculate expected frequencies for each class. (c) Perform a chi-square GOF test for a uniform distribution, using the 5 percent level of significance. 10 22 58

    Null and Alternate Hypothesis - Chi Square

    Can people really identify their favorite brand of cola? Volunteers tasted Coca-Cola Classic, Pepsi, Diet Coke, and Diet Pepsi, with the results shown below (see attachment). Research question: At α = .05, is the correctness of the prediction different for the two types of cola drinkers? Could you identify your favorite brand i

    Chi-Square Applications of Viewing Guides

    12. For many years TV executives used the guideline that 30 percent of the audience were watching each of the prime-time networks and 10 percent were watching cable stations on a weekday night. A random sample of 500 viewers in the Tampa-St. Petersburg, Florida, area last Monday night showed that 165 homes were tuned in to the

    Test of Independence - Couples in the Workforce

    Samples taken in three cities, Anchorage, Atlanta, and Minneapolis, were used to learn about the percentage of married couples with both the husband and wife in the workforce (USA Today, January 15, 2006). Analyze the following data to see whether both the husband and wife being in the workforce is independent of location. Use

    Test of Independence - Hours of Sleep

    The National Sleep Foundation used a survey to determine whether hours of sleeping per night are independent of age (Newsweek, January 19, 2004). The following show the hours of sleep on weeknights for a sample of individuals age 49 and younger and for a sample of individuals age 50 and older. See attachment file for table

    Goodness of Fit Test - Automobile Accidents Per Day

    The number of automobile accidents per day in a particular city is believed to have a Poisson distribution. A sample of 80 days during the past year gives the following data. Do these data support the belief that the number of accidents per day has a Poisson distribution? Use a=.05 Number of Accidents Observed Frequency (d

    Goodness of Fit Test - Occurrences per Time Period

    Data on the number of occurrences per time period and observed frequencies follow. Use a=.05 and the goodness of fit test to see whether the data fit a Poisson distribution. Number of Occurrences Observed Frequency 0 39 1 30 2 30 3