500 câu trắc nghiệm Kinh tế lượng – 9A

Determine which plot shows the strongest linear correlation.
7)
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8) Find the best predicted value of y corresponding to the given value of x. \(\hat y\) = 3x. Also, \({\bar y}\) = 12.75. What is the best predicted value of y for x = 2.5?
○ 7.5
○ 2.826
● 12.75
○ 0.942

9) The regression equation relating attitude rating (x) and job performance rating (y) for the \(\hat y\) = 11.7 + 1.02x. Ten pairs of data were used to obtain the equation. The same data yield r = 0.863 and \({\bar y}\) = 80.1. What is the best predicted job performance rating for a person whose attitude rating is 70?
● 83.1
○ 81.9
○ 12.6
○ 80.1

Use the given data to find the equation of the regression line. Round the final values to three significant digits, if necessary.
10)

● \(\hat y\) = 3.0x
○ \(\hat y\) = 0.15 + 3.0x
○ \(\hat y\) = 2.8x
○ \(\hat y\) = 0.15 + 2.8x

Is the data point, P, an outlier, an influential point, both, or neither?
11)

○ Outlier
● Both
○ Influential point
○ Neither

Use the given information to find the coefficient of determination.
12) Find the coefficient of determination, given that the value of the linear correlation coefficient, r, is
-0.721.
○ 0.721
● 0.520
○ 0.480
○ 0.279

Use the computer display to answer the question.
13) A collection of paired data consists of the number of years that students have studied Spanish and their scores on a Spanish language proficiency test. A computer program was used to obtain the least squares linear regression line and the computer output is shown below. Along with the paired sample data, the program was also given an x value of 2 (years of study) to be used for predicting test score.

The regression equation is: Score = 31.55 + 10.90 Years.

S = 5.651 R-Sq = 83.0% R-Sq (Adj) = 82.7%

Predicted values

If a person studies 4.5 years, what is the single value that is the best predicted test score? Assume that there is a significant linear correlation between years of study and test score.
○ 53.35
○ 49.1
○ 83.0
● 80.6