ECN 221 Exam 3
An ANOVA procedure is used for data that were obtained from four sample groups each comprised of five observations. The degrees of freedom for the critical value of F are _____.
3 and 16
correlation coefficient
A measure of the strength of the relationship between two variables is the _____.
H0: μ ≥ 85 vs Ha: μ < 85
A student believes that the average grade on the final examination in statistics is at least 85. She plans on taking a sample to test her belief. The correct set of hypotheses is _____.
may be rejected or not rejected at the 1% level
If a hypothesis is rejected at a 5% level of significance, it _____.
p1-P2 > 0
If the alternative hypothesis is that proportion of items in population 1 is larger than the proportion of items in population 2, then the null hypothesis should be _____.
must also be positive
If the coefficient of correlation is a positive value, then the slope of the regression line _____.
the correct decision has been made
In hypothesis testing, if the null hypothesis has been rejected when the alternative hypothesis has been true, _____.
The F test and the t test may or may not yield the same results.
In simple linear regression analysis, which of the following is NOT true?
least squares line
Larger values of r2 imply that the observations are more closely grouped about the _____.
In a regression analysis, if r2 = 1, then _____
SSE must be equal to 0
In a regression analysis, if r2 = 1, then ____
SSR = SST
a factor
The independent variable of interest in an ANOVA procedure is called _____.
Coefficient of determination
The proportion of the variation in the dependent variable y that is explained by the estimated regression equation is measured by the _____.
normal distribution
The sampling distribution of P1 - P2 is approximated by a _____.
p-value and critical value
Two approaches to drawing a conclusion in a hypothesis test are _____
SST=SSR + SSE
Which of the following is correct? SST = SSR + SSE SSE=SSR +SST SST=(SSR)^2 F=SSR/SSE SSR=SSE+SST
A Type II error is committed when
a true alternative hypothesis is mistakenly rejected
If the coefficient of determination is a positive value, then the regression equation _____.
could have either a positive or a negative slope
If all the points of a scatter diagram lie on the least squares regression line, then the coefficient of determination for these variables based on these data _____.
is 1
SSE can never be _____.
larger than SST
It is possible for the coefficient of determination to be _____.
less than 1
When the rejection region is in the lower tail of the sampling distribution, the p-value is the area under the curve _____.
less than or equal to the test statistic
The standard error of X1 - X2 is the
standard deviation of the sampling distribution of X1 - X2
In hypothesis testing, the alternative hypothesis is _____.
the hypothesis concluded to be true if the null hypothesis is rejected
A procedure used for finding the equation of a straight line that provides the best approximation for the relationship between the independent and dependent variables is ______.
the least squares method