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Chi-Squared Test

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

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 / NONPARAMETRIC METHODS: CHI -SQUARE APPLICATIONS

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

Hypothesis Test Question with Conclusion

The safety director of Honda USA took samples at random from the file of minor work-related accidents and classified them according to the time the accident took place. Time No. of Accidents Time No. of Accidents 8 up to 9 a.m. 61 up to 2 p.m. 7 9 u

Chi square test of independence..

In an epidemic of a certain disease, 920 children contracted the disease. Of these, 400 received no treatment, and of those, 98 suffered after-effects. Of the remainder who did receive treatment, 162 suffered after-effects. Show that chi squared = 4.90 and test the hypothesis that the treatment was not effective.

Chi-Square Tests

Question 1 a. State the hypothesis b. Find the critical value. c. Compute the test value. d. Make the decision. e. Summarize the results. In a recent study, the following percentages of U.S. retail car sales based on size were reported: 28.1%small, 47.8% midsize, 7% large, and 17.1% luxury. A recent survey of retail

Chi square Hypothesis testing

Level of education attained by the women from a rural region is divided into three categories: can read/write degree; primary degree; secondary and above degree. A demographer estimates that 28% of them have can read/write degree, 61% have primary degree and 11% have higher secondary degree. In order to verify these percentages,

Chi-square goodness of fit analysis

An EMT Service keeps records of emergency calls. A study of 150 five-minute time intervals resulted in the distribution of number of calls as follows. For example, during 18 of the five-minute intervals, no calls occurred. USe the chi-sqaure goodness-of-fit test and significance level =.01 to determine whether this distributi

Chi square hypothesis test for independence of variables

1) Two hundred managers from various levels were randomly selected and interviewed regarding their concern about environmental issues. The response of each person was tallied into one of three categories: no concern, some concern, and great concern. The results were: Level of Management No Concern Some Concern Great Concern To

Rank correlation and chi square

15.12 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 th

Chi_Sq Inferential test. How would I put this together for testing?

Say we collected salary figures from our HR department and we knew to the exact dollar what everyone made this year and last year (interval/ratio data). We ran a parametric test (z or t) to see if there was a difference and our answer was significant at the 0.05 level. But let us assume that for some reason HR did not want to

Chi square goodness of fit test, ANOVA

1) A sales manager is curious whether day of the week makes any difference in number of sales made. She decides to sample the records to determine if sales are distributed evenly throughout the six-day workweek. The sample results are: Day of Week Sales Made Monday 6 Tuesday 9 Wednesday 11 Thursday 10 Friday 10 Saturda

Statistical Independence Testing

P(A and B) = P(A) P(B) OR P(A|B) = P(A) BUT, I seem to recall reading elsewhere that while an inequality can be assumed to mean DEPENDENCE, and equality may or may NOT mean independence. Is that correct? If so, how can one really PROVE independence?

Nonparametric methods: chi-square

13. The director of advertising for the Carolina Sun Times, the largest newspaper in the Carolinas, is studying the relationship between the type of community in which a subscriber resides and the section of the newspaper he or she reads first. For a sample of readers, she collected the following sample information.

Test for difference in mean using ANOVA and Chi Square

There are three hospitals in the Tulsa, Oklahoma, area. The following data show the number of outpatient surgeries performed at each hospital last week. At the .05 significance level, can we conclude there is a difference in the mean number of surgeries performed by hospital or by day of the week? Day Number of Surgeries