BNAD 277 EXAM 1 CONCEPTUAL REVIEW QUESTIONS
If there are five treatments under study, the number of pairwise comparisons is _______.
10
In a two-way ANOVA test, how many null hypotheses are tested
2
What are the degrees of freedom for the Jarque-Bera goodness-of-fit test for normality?
2
In the test for comparing two population means when population variances are unknown and unequal, a student calculates the degrees of freedom using the proper formula as 61.75. Per the t-tableyou were given, how many degrees of freedom should the student use to find the critical value or p-value of the test?
60
A particular personal trainer works primarily with track and field athletes. She believes that her clients run faster after going through her program for six weeks. How might she test that claim?
A matched-pairs hypothesis test for ud.
What type of test for population means should be performed when examining a situation in which employees are first tested, then trained, and finally retested?
A t test under dependent or matched-pairs sampling.
Suppose you want to determine if gender and major are dependent. Which of the following tests should you use?
Chi-square test for independence
A goodness-of-fit test analyzestwo qualitative variables whereas a chi-square test of a contingency table is for a single qualitative variable.
False
ANOVA is a statistical technique used to determine if differences exist between the means of two populations
False
For a multinomial experiment with k categories, the goodness-of-fit test statistic is assumed to follow a chi-square distribution with k degrees of freedom
False
If the underlying populations cannot be assumed to be normal, then by the central limit theorem, the sampling distribution of x1−x2 is approximately normal only if the sum of the sample observations is sufficiently large—that is, when n1+n2≥30
False
The same formulas are used to computethe test statistic whetherthe hypothesized difference between population proportions is zero or not
False
The t statistic is used to estimate the difference between two population proportions.
False
Two random samples are considered independent if the observations in the first sample are different from the observations of the second sample
False
You would like to determine if there is a higher proportionof smoking among women than among men in a neighborhood. Let women and men be represented by populations 1 and 2, respectively. Which of the following hypotheses is relevant to this claim?
H0: p1-p2≤ 0, HA:p1-p2> 0
A demographer wants to measure life expectancy in countries 1 and 2. Let u1 and u2 denote the mean life expectancy in countries 1 and 2, respectively. Specify the hypothesis to determine if life expectancy in country 1 is more than 10 years higher than in country 2
H0: u1-u2≤ 10, HA: u1-u2> 10
Which of the following null hypotheses is used to test if five population proportions are the same
H0:p1= p2= p3= p4= p5= 0.20
Which of the following pairs of hypotheses are used to test if the mean of the first population is smaller than the mean of the second population, using independent random sampling?
H0:u1-u2≥ 0, HA: u1-u2< 0
Which of the following is the correct alternative hypothesis for theJarque-Bera test for normality?
HA:the data is NOT normally distributed
Suppose you want to perform a test to compare the mean GPA of all freshmen with the mean GPA of all sophomores in a college? What type of sampling is required for this test?
Independent sampling with quantitativedata
When comparing two population means, their hypothesized difference _________.
May assume any value
For a chi-square goodness-of-fit test, the expected category frequencies are calculated using the sample category proportions.
True
For a chi-square test of a contingency table, the degrees of freedom are calculated as (r−1)(c−1) where r and c are the number of rows and columns in the contingency table
True
For the Jarque-Bera test for normality, the test statistic is assumed to have a chi-square distribution with two degrees of freedom.
True
In the case when "sigma 1" and "sigma 2" are unknown and can be assumed equal, we can calculate a pooled estimate of the variance
True
The chi-square test statistic measures the difference between the observed frequencies and the expected frequencies assuming the null hypothesis is true.
True
The difference between the two sample means is an interval estimator of the difference between two population means.
True
We use ANOVA to test for differences between population means by examining the amount of variability between the samples relative to the amount of variability within the samples
True
When using Fisher's least difference (LSD) method at some stated significance level α, the probability of committing a Type I error increases as the number of pairwise comparisons increases.
True
A 7,000-seat theater is interested in determining whether there is a difference in attendance between shows on Tuesday evening and those on Wednesday evening. Two independent samples of 25 weeks are collected for Tuesday and Wednesday. The mean attendance on Tuesday evening is calculated as 5,500, while the mean attendance on Wednesday evening is calculated as 5,850. The known population standard deviation for attendance on Tuesday evening is 550 and the known population standard deviation for attendance on Wednesday evening is 445. Which of the following is the absolute value of the appropriate test statistic
Zstat= 2.473
For the goodness-of-fit test, the chi-square test statistic will _________________.
be greater than or equal to zero
Packaged candies have three different types of colors. Suppose you want to determine if the population proportion of each color is the same. The most appropriate test is the __________.
goodness-of-fit test for a multinomial experiment
For the goodness-of-fit test, the sum of the expected frequencies must equal ______.
n
The chi-square test of independence is valid when the expected cell frequencies are _____.
pairwise comparisons
When using Fisher's LSD method at some stated significance level, the probability of committing a Type I error increases as the number of _________________________.
pairwise comparisons increase
If units withineach block are randomly assigned to each of the treatments, then the design of the experiment is referred to as a ______________________.
randomized block design
If the amount of variability between treatments is significantly greater than the amount of variability within treatments, then _________.
reject the null hypothesis of equal population mean
When testing the difference between two population means under independent sampling, we use the z distribution if _________ .
the population variances are known
For the chi-square test of independence, the expected cell frequencies are found as ______.`
the row total multiplied by the column total divided by the sample size
The calculation of the Jarque-Bera test statistic involves_____.
the sample size, skewness, and kurtosis
The chi-square test of independence is a test of independence for _______.
two qualitative variable
