Exam 2

In a one-way Analysis of Variance, the total variation is divisible into __________ component(s).

2

In an Analysis of Variance with 4 groups, each containing 12 respondents: Calculate the between-group degrees of freedom.

3

The degrees of freedom for a chi-square test applied to a cross-tabulation with 4 rows and 3 columns is equal to

6

A researcher takes a sample and wants to compare the results to the population from which it was drawn. The independent variable consists of three categories and the dependent variable is measured at the ordinal level. What test would the researcher use to see if results are significant?

??

If the obtained t value is greater than the critical t value, we

??

In a Two-way Analysis of Variance, the between-groups sum of squares can be divided into __________ components.

??

The UNBIASED estimate of the standard error of the mean s subscript top enclose X end subscript is

??

What percent of members in a random sample have an equal chance of being selected?

??

Which of the following is FALSE of nonparametric tests

??

Which of the following statements about the t test for dependent samples is true?

??

if the null hypothesis is true, there is no difference between population means.

??

The UNBIASED estimate of the standard error of the mean s subscript top enclose X end subscript is:

???

What percent of members in a random sample have an equal chance of being selected?

???

Which is NOT true of an Analysis of Variance?

All data must be selected randomly.

With respect to α (alpha), which of the following statements is true?

Alpha is the level of probability at which the null hypothesis can be rejected with confidence

Groups in an Analysis of Variance are typically formed based on a __________ measure.

Categorical

Which statement is true of α (alpha)?

Conventionally, social researchers set α = .05.

Which of the following does NOT exemplify a research hypothesis:

Drivers of SUV's have the same personality type as drivers of pickup trucks.

A chi-square tests depends on the interval level of measurement.

False

ANOVA is generally used to compare less than three groups.

False

Compared with the 95% confidence interval, the 99% confidence interval is narrower.

False

Finding a statistically significant difference between means provides researchers with the extent in which this result will occur in the population.

False

In ANOVA, if the F ratio is larger than the critical value the groups are the same in the population.

False

In ANOVA, the dependent variable is measured at the nominal level.

False

In a chi-square test of significance, the dependent variable is measured at the interval level.

False

In a random sample all members of the population do not have a chance of selection.

False

Testing the difference between means requires measurement at the ordinal level.

False

Unfortunately, sampling error cannot be calculated.

False

Software products utilize this test to assess whether sample variances are so dissimilar that the notion that they are the same must be rejected

Levene Test

When estimating a population mean, the degrees of freedom, df, is:

N-1

Which variety of nonrandom sampling takes proportions into consideration?

Quota

This difference between the sample and population results regardless of how well the sampling plan has been designed.

Sampling error

Taking a simple random sample from each of a number of subgroups (for example, lower-income Catholics, middle-income Protestants, and so on) is what sampling method?

Stratified sampling

A chi-square test is a nonparametric test of significance.

True

Accepting the null hypothesis for the means of two independent groups indicates that there is no statistically significant difference.

True

In ANOVA, the dependent variable is measured at the interval level.

True

Rejecting the null hypothesis for two independent groups means they are different in the population.

True

Testing the difference between means or proportions requires random sampling.

True

The critical value for assessing the difference between two proportions at the 0.05 level is 1.96.

True

When we risk committing a Type I error:

We risk rejecting the null hypothesis when it is true.

A researcher takes a sample and wants to compare the results to the population from which it was drawn. The independent variable is "gender" and the dependent variable is a yes/no response to whether they favor the abortion. What test would the researcher use to see if results are significant?

a chi-square test

Parametric tests require

a normal distribution

Parametric comes from the term 'parameter' which refers to

any characteristic of a population

Which of the following is true of the sampling distribution of means?

approximates the normal curve equal to the population mean smaller than the standard deviation of population

Small expected frequencies cause the value of the chi-square statistic to

become much larger

As the observed frequencies get closer to the expected frequencies, the value of the chi-square statistic

becomes smaller

The variation observed between group means is referred to as

between group variation

The mean square is

calculated by dividing the sum of squares within by the degrees of freedom within. calculated by dividing the sum of squares between by the degrees of freedom between. is a method for assessing variation in conjunction with the sums of squares measures.

This term is synonymous with multistage sampling

cluster

This term is synonymous with multistage sampling:

cluster

When we test hypotheses of differences between means, we

compare our results to that of a probability distribution. Test to see if our obtained difference could have happened by chance. Calculate a type of z score to locate our difference on a probability distribution.

Which of the following is a requirement for computing the F ratio?

comparing two or more independent means. a normal distribution. Random sampling.

We use the Analysis of Variance rather than the t ratio when more than two groups are involved because

decreases the likelihood of making a Type I error. Less time consuming to make the necessary calculations. Decreases the likelihood of making a Type I error.

The F Ratio is calculated by

dividing the mean square between by the mean square within

The frequencies proposed under the terms of the null hypothesis are the

expected frequencies

Choose the correct statement

if the null hypothesis is true, there is no difference between population means.

When increasing our level of confidence from 95% to 99%, the margin of error

increases

Analysis of Variance should only be used on __________ level data.

interval

The standard error of the mean

is the standard deviation of a theoretical sampling distribution

The standard error of the mean

is the standard deviation of a theoretical sampling distribution.

When the null hypothesis is rejected:

it is unlikely that the difference between means is a result of sampling error.

The greater the degrees of freedom, the _____ the sample size and the _____ the t distribution approximates the normal distribution

larger, closer

The greater the degrees of freedom, the __________ the sample size and the __________ the t distribution approximates the normal distribution

larger, closer

When increasing the level of confidence from 95% to 99%, we

lose precision but gain confidence that our answer interval is accurate.

Compared to the .05 level of significance, the .01 level of significance

means a lower probability of the obtained difference being a result of sampling error.

Which of the following is NOT a requirement of the median test?

nominal data

Nonparametric tests REQUIRE

none of the above are required

The set of frequencies obtained in an actual frequency distribution are the

observed frequencies

Tukey's HSD test is used:

only after the analysis of variance has been computed

Which variety of nonrandom sampling takes proportions into consideration?

quota

The difference between the sample mean and the population mean is called

sampling error

This difference between the sample and population results regardless of how well the sampling plan has been designed.

sampling error

Taking a simple random sample from each of a number of subgroups (for example, lower-income Catholics, middle-income Protestants, and so on) is what sampling method?

stratified sampling

Researchers deal with the uncertainty in estimating the standard error of the mean with this distribution

t

The t distribution more closely approximates the distribution of the normal curve when

the degrees of freedom increase

The larger the value of our obtained t

the less probable that our results are due to chance alone.

The median test determines

the likelihood that the samples were drawn from populations with equal medians.

The q value in Tukey's HSD depends on

the number of group means being compared.

The "power" of a test refers to

the probability of correctly rejecting a false null hypothesis.

As β (beta) decreases

the probability of making a Type I error increases.

Nonparametric tests are useful when:

the researcher cannot assume normality. there is a small number of cases. data are not measured at the interval level.

A frequency distribution of a large number of random sample means which have been drawn from the same population is called:

the sampling distribution of means

Which of the following is true of the sampling distribution of means?

the sampling distribution of means approximates the normal curve. is equal to the population mean. smaller than the standard deviation of the population.

A frequency distribution of a large number of random sample means which have been drawn from the same population is called

the sampling distribution of means.

A chi-square test should be used with caution when

there is an expected frequency <5

Analysis of Variance should be used on __________ or more independent means.

three

A 99% confidence interval is less precise than a 95% confidence interval.

true

a 99% confidence interval is less precise than a 95% confidence interval

true

If a chi-square expected frequency is less than 10, one should

use Yates' correction

The variation found among raw scores in a particular group is referred to as:

within group variation

The sum of squares is the method for measuring variation:

within groups. between groups. for the total sample.