Describe a goodness-of-fit test. What assumptions are made when using a goodness-of-fit test?

Chi-square tests
asked 2021-01-30
Describe a goodness-of-fit test. What assumptions are made when using a goodness-of-fit test?

Answers (1)

Step 1
The chi-square is a non-parametric test which is used for comparing the categorical variables. The chi-square goodness of fit test helps in determining how the observed distribution fits the expected distribution. It is used for comparing the observed data with the expected data. In other words, it determines whether the data of the sample is reliable with the population distribution or not.
Step 2
-The sample drawn must be randomly selected.
-The variable considered for the study must be a categorical variable.
-Different levels of categorical variable must be mutually exclusive.
-Each of the observations from the sample must be independent of each other.
-Each level of the categorical variable must have at least 5 expected frequencies.
Best answer

expert advice

Need a better answer?

Relevant Questions

asked 2020-11-08
Distinguish the difference (purpose) between the two different types of chi-square
1.Chi-square test for independence (CTI)
2.Chi-square test for goodness of fit (CGF)
3.What type of variables are we using for a chi-square?
asked 2020-10-20
A) Explain why the chi-square goodness-of-fit test is not an appropriate way to find out.
B) What might you do instead of weighing the nuts in order to use a x2 test?
Nuts A company says its premium mixture of nuts con- tains 10% Brazil nuts, 20% cashews, 20% almonds, and 10% hazelnuts, and the rest are peanuts. You buy a large can and separate the various kinds of nuts. Upon weigh- ing them, you find there are 112 grams of Brazil nuts, 183 grams of cashews, 207 grams of almonds, 71 grams of hazelnuts, and 446 grams of peanuts. You wonder whether your mix is significantly different from what the company advertises.
asked 2021-03-05
For each of the following situations, state whether you’d use a chi-square goodness-of-fit test, a chi-square test of homogeneity, a chi-square test of independence, or some other statistical test:
a) Is the quality of a car affected by what day it was built? A car manufacturer examines a random sample of the warranty claims filed over the past two years to test whether defects are randomly distributed across days of the work week.
b) A medical researcher wants to know if blood cholesterol level is related to heart disease. She examines a database of 10,000 patients, testing whether the cholesterol level (in milligrams) is related to whether or not a person has heart disease.
c) A student wants to find out whether political leaning (liberal, moderate, or conservative) is related to choice of major. He surveys 500 randomly chosen students and performs a test.
asked 2020-12-09
You want to know whether people in different regions of the country are equally likely to vote Sarah Duterte, Peter Cayetano, Mar Roxas, or any candidate other than the three in the next election. You would use
A. chi-square test of independence.
B. either chi-square test (goodness-of-fit or test of independence), depending on how you set up the problem.
C. chi-square goodness-of-fit test.
D. both chi-square tests, in order to check the results of one with the other.
asked 2021-02-12
For the following situations, identify the test you would run to analyze the data:
A marketing firm producing costumes is interested in studying consumer behavior in the context of purchase decision of costumes in a specific market. This company is a major player in the costume market that is characterized by intense competition. The company would like to know in particular whether the income level of the consumers (measured as lower, middle, upper middle, and upper class) influences their choice of costume type. They are specifically focused on four types of costumes (funny costumes, scary costumes, clever costumes, and boring costumes).
a. Chi-Square Goodness of Fit
b. Frequencies
c. Descriptive Statistics
d. Chi-Square of Independence
asked 2020-12-03
Explain why the chi-square is called a goodness-of-fit test.
asked 2020-10-26
Find the pattern of the data of Chi-square goodness-of-fit from two options.
asked 2021-03-02

The following observations are lifetimes (days) subsequent to diagnosis for individuals suffering from blood cancer ("A Goodness of Fit Approach to the Class of Life Distributions with Unknown Age," Quality and Reliability Engr. Intl., \(2012: 761-766): 115, 181, 255, 418, 441, 461, 516, 739, 743, 789, 807, 865, 924, 983, 1025, 1062, 1063, 1165, 1191, 1222, 1222, 1251, 1277, 1290, 1357, 1369, 1408, 1455, 1278, 1519, 1578, 1578, 1599, 1603, 1605, 1696, 1735, 1799, 1815, 1852, 1899, 1925, 1965.\)
a) can a confidence interval for true average lifetime be calculated without assuming anything about the nature of the lifetime distribution? Explain your reasoning. [Note: A normal probability plot of data exhibits a reasonably linear pattern.]
b) Calculate and interpret a confidence interval with a 99% confidence level for true average lifetime. [Hint: mean \(= 1191.6, s = 506.6\).]

asked 2021-02-13
Suppose I gave you a bag of M&M’s, but I didn’t let you see the original packaging so you can’t determine which plant made the M& M’s. Your job is to count the number of candies of each color in your bag and figure out which plant made your bag. What test should you do to determine this?
asked 2020-12-25
Explain what changes would be required so that you could analyze the hypothesis using a chi-square test. For instance, rather than looking at test scores as a range from 0 to 100, you could change the variable to low, medium, or high. What advantages and disadvantages do you see in using this approach? Which is the better option for this hypothesis, the parametric approach or nonparametric approach?

You might be interested in