Exam 15: Chi-Squared Tests

To produce expected values for a test of a contingency table, you multiply estimated joint probabilities for each cell by the total sample size, n.

The null hypothesis in a chi-squared test of a contingency table is that the two nominal variables are ____________________.

The number of degrees of freedom for a contingency table with r rows and c columns is:

The chi-squared distribution is used in:

To determine whether a single coin is fair, the coin was tossed 200 times.The observed frequencies with which each of the two sides of the coin turned up are recorded as 112 heads and 88 tails.Is the coin fair? Use a=.05

Five types of apples are displayed side by side in several supermarkets in the city of Miami.It was noted that in one day, 180 customers purchased apples.Of these, 30 picked type A, 40 picked type B, 25 picked type C, 35 picked type D, and 50 picked type E.In Miami, can you conclude at the 5% significance level that there is a preferred type of apples?

How do you calculate the expected frequency for one cell in a goodness-of-fit test?

If we want to conduct a two-tail test of a population proportion, we can employ:

Explain what is meant by the rule of five and what you should do if this rule is not met.

A(n) ____________________ experiment is like a binomial experiment except it contains two or more categories.

A large value of a chi-squared test statistic in a test of a contingency table leads you to conclude the two variables are ____________________.

A chi-squared goodness-of-fit test is always a two-tailed test.

If each element in a population is classified into one and only one of several categories, the population is:

A large chi-squared test statistic in a test of a contingency table means you conclude:

To address whether two variables are related in a contingency table, the null hypothesis, H₀, says that

A chi-squared test of a contingency table can be used to infer that differences exist between ____________________ populations of nominal variables.

A chi-squared test of a contingency table with 6 degrees of freedom results in a test statistic of 13.25.Using the chi-squared table, the most accurate statement that can be made about the p-value for this test is that p-value is greater than .025 but smaller than .05.

Student Absenteeism Consider a multinomial experiment involving n = 200 students of a large high school.The attendance department recorded the number of students who were absent during the weekdays.The null hypothesis to be tested is: H₀: p₁ = .10, p₂ = .25, p₃ = .30, p₄ = .20, p₅ = .15. -{Student Absenteeism Narrative} Review the previous results.What is the effect of decreasing the sample size?

If two events A and B are independent, the P(A and B) = P(A) + P(B).

Which of the following tests is used to analyze nominal data?