Question

Econ 3050

Q7. When every member of the accessible population has an equal chance of being selected to participate in the study, the researcher is using:

a)     Simple random sampling

b)     Stratified random sampling

c)     Convenience sampling

d)     Purposive random sampling

Q8. A regression line has been found that has nearly all the points lying directly on the line, and only a few of them stray away from the line. Therefore, the standard error of the estimate is likely to be

Huge.

Small.

0.

Undefined.

Q9. Correlation coefficient ranges from _______   to ____________.

a)     - 1 to 0.

b)     0 to 1.

c)     -1 to 1.

d)     None of the above.

Q10. The correlation coefficient of determination is the:

a)     Ratio of the explained variation to the total deviation.

b)     Ratio of the unexplained deviation to the explained deviation.

c)     Ratio of the unexplained deviation to the total variation.

d)     Ratio of the explained variation to the total variation.

Q11. If the correlation coefficient r = 0.5 then the coefficient of determination is

a)     0.10

b)     0.25

c)     1.00

d)     2.50

Q12. Which one of the following is NOT appropriate for studying the relationship between two quantitative variables?

Scatterplot

Bar chart

Correlation

Regression

Q13. In regression, an independent variable is sometimes called a response variable

True

False

Q14. The simple linear regression equation can be written yˆ = b₀ + b₁x. In the simple linear regression equation, the symbol yˆ represents

Average or predicted response

Estimated intercept

Estimated slope

Explanatory variable

Answer 1

Q7 a. Simple random sampling. Each unit has an equal chance of being selected in the sample in the case of simple random sampling.

Q8. Small. Standard error tells us how well the sample mean represents the population mean. A large standard error means there is a lot of variability.

Q9. C. Correlation coefficient always lies betwee -1 and 1. -1 and +1 indicate strong linear relationship between the two variables.

Q10. d) Total of the explained variation to the total variation. It is the percent of the variation that can be explained by the regression equation.