stats 2 exam 2 def

An important application of the chi-square distribution is making inferences about a single population variance. testing for goodness of fit. testing for the independence of two categorical variables. All of these alternatives are correct.

All of these alternatives are correct.

Which of the following is not a required assumption for the analysis of variance? The random variable of interest for each population has a normal probability distribution. The variance associated with the random variable must be the same for all populations. At least 2 populations are under consideration. Populations under consideration have equal means.

Populations under consideration have equal means.

When �Alpha 1 and �Alpha 2 are unknown we will: Use the sample standard deviations, s1 and s2, as estimates of alpha�1 and alpha�2 Assume .05 as level of significance Assume that the populations have equal means Always use matched samples design

Use the sample standard deviations, s1 and s2, as estimates of alpha �1 and alpha�2

When conducting a hypothesis test comparing two populations with independent samples, each observation from one sample is related to an observation from the other sample. True False

false

When performing matched-samples test the level of significance α is always equal to 0.05 True False

false

The hypothesis statement: H0 : μ1 - μ2 = 0 is an example of a two-tail hypothesis test. True False

true

When the confidence interval for the difference between two means does not include zero when testing H0 : μ1 - μ2 = 0 , we have support that a significant difference between population means does exist. True False

true

The test statistic for goodness of fit has a chi-square distribution with k - 1 degrees of freedom provided that the expected frequencies for all categories are 5 or more. 10 or more. k or more. 2k.

5 or more.

If we are interested in testing whether the proportion of items in population 1 is larger than the proportion of items in population 2, the null hypothesis should state p1 - p2 < 0. alternative hypothesis should state p1 - p2 = 0. alternative hypothesis should state p1 - p2 > 0. alternative hypothesis should state p1 - p2 < 0.

alternative hypothesis should state p1 - p2 > 0.

If two independent large samples are taken from two populations, the sampling distribution of the difference between the two sample means can be approximated by any distribution. will have a variance of one. can be approximated by a normal distribution. will have a mean of one.

can be approximated by a normal distribution.

The sampling distribution for a goodness of fit test is the _____ distribution. F t normal chi-square

chi-square

An experimental design where the experimental units are randomly assigned to the treatments is known as _____ design. factor block random factor completely randomized randomized treatment

completely randomized

In the ANOVA, treatments refer to experimental units. different levels of a factor. the dependent variables. statistical applications.

different levels of a factor.

In order to determine whether or not the means of two populations are equal, a t test must be performed. an analysis of variance must be performed. either a t test or an analysis of variance can be performed. a chi-square test can be performed.

either a t test or an analysis of variance can be performed.

In an ANOVA procedure, a term that means the same as the term "variable" is factor. treatment. replication. within-variance.

factor

The independent variable of interest in an ANOVA procedure is called a partition. treatment. response. factor.

factor

In factorial designs, the response produced when the treatments of one factor interact with the treatments of another in influencing the response variable is known as main effect. replication. interaction. error.

interaction

When each data value in one sample is matched with a corresponding data value in another sample, the samples are known as _____ samples. pooled independent proportional matched

matched

Of the two production methods, a company wants to identify the method with the smaller population mean completion time. One sample of workers is selected and each worker first uses one method and then uses the other method. The sampling procedure being used to collect completion time data is based on​ ​matched samples. ​worker samples. ​pooled samples. ​independent samples.

matched samples.

A population where each of its element is assigned to one and only one of several classes or categories is a _____ population. multinomial Uniform normal binomial

multinomial

When developing an interval estimate for the difference between two population means with sample sizes of n1 and n2, n1 must be equal to n2. n1 must be smaller than n2. n1 must be larger than n2. n1 and n2 can be of different sizes.

n1 and n2 can be of different sizes.

Marascuilo procedure is used to test for a significant difference between pairs of population proportions. means. variances. standard deviations.

proportions

The required condition for using an ANOVA procedure on data from several populations is that the selected samples are dependent on each other. response variables from samples are all uniform. sampled populations have equal variances. sampled populations have equal means.

sampled populations have equal variances.

In the analysis of variance procedure (ANOVA), "factor" refers to the dependent variable. the independent variable. different levels of a treatment. the critical value of F.

the independent variable.

The ANOVA procedure is a statistical approach for determining whether or not the means of _____ are equal. two samples two or more samples four populations three or more populations

three or more populations