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Chi-Squared Test

Chi Squared Distribution: Concentration of Lactic Acid

1. Suppose that we will sample 20 chunks of cheese in Example 7.2.1. Let T = .... where Xi is the concentration of lactic acid in the ith chunk. Assume that sigma^2 = 0.09. What number c satisfies Pr(T<c)=0.9? Please see the attached file for the fully formatted question.


When testing for goodness-of-fit with Benford's law, it is necessary to combine categories because not all expected values are at least 5. I don't understand this , use one category with leading digits of 1 , a second category with leading digits of 2,3,4 5 and a third category with leading digits of 6,7,8,9.Are the expected va

Chi Square Test for independence of attributes

Question : Prof. H. Elp Me- John, a mathematics counselor, is interested in the relationship between math anxiety and the successful completion of the introductory college math course. A random sample of 300 college students enrolled in the introductory college math course were given a test to measure their anxiety level on

Chi Square Test for Independence of Attributes

Question : A quality control engineer wants to compare the production process of parts manufactured by four different companies. The engineer randomly samples a total of 270 parts from the four companies and summarizes the results in the following table. Based upon the results of the sample, can the quality control engineer c

Statistics Questions

Should Statistics Be a Required Course in College? Yes No Republican 10 26 Democrat 15 17 1. Cell 1,1 (Yes, Republican) Expected Value = 2. Cell 2,2 (No, Democrat) Expected Value = Cell 2,1 (No, Republican) Expected value = Cell 1,2 (Yes, Democrat) Expected value = 3. What is the result of this anal

Multinomial experiments: Chi square test

Births. Randomly selected births records were obtained and results are listed in the table below (based on data from the National Vital statistics Report, Vol. 49, No.1). Use a 0.05 significance level to test the reasonable claim that births occur with equal frequency on the different days of the week. How might the apparent

Interpretation of results of a chi-square test

Interpretation of results of a chi-square test:"Effects of crude oils on the Gastroinstestinal parasites of two species of Marine fish" For full details of problem, see attached JPG file.

Using a Chi Square Test: Types of Vehicles

Question: 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. (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 ind

Chi Square test of Independence for Pricing scam

1. In a study of store checkout scanning systems, samples of purchases were used to compare the scanned process to the posted prices. The accompanying table summaries results for a sample of 819 items. Regular-priced items Advertised-special items Undercharge 20 7 Overcharge 15 29 Correct price 384 3

Goodness of Fit Test

The results from a survey are below: Item Number of Votes Doughnuts 20 Apple Turnovers 6 Doughnut Holes 5 Bismarcks 4 Pomegranate Cookies 5 Based upon all of this information, do a "goodness-of-fit" test to see if the distributions are th

Chi Square

Explain why the value at the bottom left corner on the x axis of the Chi Square distribution curve is zero.

Chi square

Can right tailed, left tailed, and two tailed distributions be tested with the Chi Square? Explain.

Chi square

What happens to the shape of the Chi Square distribution curve as the sample size gets larger? What about when the number of cells or groups gets larger?

Smokers vs non-smokers: chi-square test

I need to find out if the percentage distribution differs for smokers and non-smokers between men and women. Use Chi-square (level of significance .05) test and need a 2 by 2 contingency table that looks like: Smokers found Yes No Males 12

Which test should I do and why?

Need full and good explanation to my query. I am wondering which stats test to use : I am doing a project which is about whether sex ratio affects the occurrence of courtship behaviour in a fish. I am also looking to see if the time at which the observations for each sex ratio affects the occurrence: Data: Time sex ratio

2 Statistics problems (Chi-square test for independence )

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

Calculatin of one sample t test and Chi square test

1. Assume that a simple random sample has been selected from a normally distributed population. Find the test statistic, a range of numbers for the P-value, critical value and state the final conclusion. Claim:- The mean bottom temperature of a fish breeding pond is less than 20 degree celcius. Sample Data:- n=56, x-bar =1

Hypothesis testing

Chapter 10, Exercise 22, page 343 Given the following hypothesis: A random sample of six resulted in the following values: 118, 105, 112, 119, 105, and 111. Using the .05 significance level, can we conclude the mean is different from 100? a. State the decision rule. b. Compute the value of the test statistic. c.

Chi Square test for Independence and Test of proportions

On pg. 612 #4 The accuracy of Polygraph Tests The data in the accompanying table summarize results from tests of the accuracy of polygraphs (based on data from the Office of Technology Assessment). Use a 0.05 significance level to test claim that whether the subject lies is independent of the polygraph indication. What do the

One criterion used to evaluate employees in the assembly section...

One criterion used to evaluate employees in the assembly section of a large factory is the number of defective pieces per 1,000 parts produced. The quality control department wants to find out whether there is a relationship between years of experience and defect rate. Since the job is repetitious, after the initial training pe

Chi square test for TV advertisement data

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 a product advertised by a celebrity spokesper

Chi square test of independence, F test and ANOVA

See attached file for full problem description. 1. A teacher figures that final grades in the statistics department are distributed as A-25%, B-25%, C-40%, D-5%, and F-5%. At the end of a randomly selected semester, the following number of grades were recorded. Determine if the grade distribution for the department is differe

Calculation of sampling error and chi-square statistic

8. A telephone survey utilized a sampling frame of 2000 numbers, and had a response rate of 25%. A question asked respondents if they preferred Brand 1, Brand 2, or Brand 3. According to the company, 35% of their customers preferred Brand 1, 35% preferred Brand 2, and 30% preferred Brand 3. The telephone survey found that 40%

Statistics Questions

1. How many different ways is it possible to get seven heads in a sample of twenty coin flips? 2.What is the probability of getting seven heads in a sample of twenty coin flips? Is this significantly different from the population in which P = 0.50 if the alpha is 0.05? 3. In which case would it be easier to reject the null

Chi Square test of Independence

I need to come up with a mean, standard deviation, histogram, and/or any other relevant calculations with the following data. Is this possible please show me what results you came up with and the process of retrieving those calculations. If not, what type of additional information is needed? Please show me examples and walk me t


ANALYSIS OF VARIANCE #10 The manager of a computer software company wishes to study the number of hours senior executives spend at their desktop computers by type of industry. The manager selected a sample of five executives from each of three industries. At the 0.05 significance level, can she conclude there is a difference in