Exam 15: Chi-Squared Tests

If you want to describe a population with more than two categories,you can use a chi-squared ____________________ test.

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

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?

A major insurance firm interviewed a random sample of 1,200 college students to find out the type of life insurance preferred,if any.The results follow: Is there evidence that life insurance preference of male students is different than that of female students? Test using the 5% level of significance.

The alternative hypothesis in a goodness-of-fit test is that none of the p_i values are equal to their values specified in H₀.

When the problem objective is to describe a population of nominal data with exactly two categories,we can employ either the z-test of a population proportion p,or the chi-squared goodness-of-fit test.

The Chairman of a committee has recently circulated pamphlets among the members,attempting to convince them that pension benefits should be the primary issue.A subsequent survey revealed the following breakdown of the members according to the plant at which they worked and the issue that they felt should be supported as the primary one. Do the data indicate at the 5% significant level that there are differences between the two plants regarding which issue should be the primary one?

Before a chi-squared test of a contingency table can be carried out,the expected values of all cells should be greater than or equal to ____________________.

For comparing two or more populations each having two or more categories,use a(n)____________________ test of a(n)____________________.

Which of the following tests is appropriate for nominal data if the problem objective is to compare two populations and there are exactly 2 categories?

In 2011,computers of Brand A controlled 25% of the market,Brand B 20%,Brand C 10%,and brand D 45%.In 2015,sample data was collected from many randomly selected stores throughout the country.Of the 1,200 computers sold,280 were Brand A,270 were Brand B,90 were Brand C,and 560 were Brand D.Has the market changed since 2011? Test at the 1% significance level.

In a goodness-of-fit test,the null hypothesis states that the data came from a normally distributed population.The researcher estimated the population mean and population standard deviation from a sample of 500 observations.In addition,the researcher used 6 standardized intervals to test for normality.Using a 5% level of significance,the critical value for this test is:

A calculus professor posted the following grade distribution guidelines for her elementary calculus class: 8% A,35% B,40% C,12% D,and 5% F.A sample of 100 elementary statistics grades at the end of last semester showed 12 As,30 Bs,35 Cs,15 Ds,and 8 Fs.Test at the 5% significance level to determine whether the actual grades deviate significantly from the posted grade distribution guidelines.

The chi-squared test for normality must follow the rule of ____________________ regarding expected values.

Suppose the value of your chi-squared test statistic in a goodness-of-fit test is equal to 0.What do you conclude?

A chi-squared test of a contingency table can be used to determine whether two nominal variables are ____________________.

If there are only two categories,the chi-squared goodness-of-fit test is the same as the z-test for p,the population proportion (as long as the sample/cell sizes meet the conditions).

All of the expected frequencies in a chi-squared goodness-of-fit test must be equal to each other.

If we use the χ² goodness-of-fit to test for the differences among 4 proportions,the degrees of freedom is equal to:

Which statistical technique is appropriate when we wish to analyze the relationship between two qualitative variables with two or more categories?