Question

name: ____ class period: ____ linear regression assignment identify if the scatter plots below show positive, negative, or no correlation. 1. 2. 3. positive / negative / no positive / negative / no positive / negative / no 4. 5. 6. regression line: y = 0.40x + 3.1 line of best fit: y = 2.8x+14.2 trend line: correlation coefficient: 0.46 correlation coefficient: 0.91 correlation coefficient: what does this mean? what does this mean? what does this mean? strong / weak positive / negative strong / weak positive / negative strong / weak positive / negative

Explanation:

Step1: Analyze scatter - plot 1

As x increases, y generally increases. So it is positive correlation.

Step2: Analyze scatter - plot 2

The points are randomly scattered with no clear upward or downward trend. So it is no correlation.

Step3: Analyze scatter - plot 3

As x increases, y generally increases. So it is positive correlation.

Step4: Analyze data set 4

The correlation coefficient is 0.46. Since it is positive and close to 0, it is weak positive correlation.

Step5: Analyze data set 5

The correlation coefficient is 0.91. Since it is positive and close to 1, it is strong positive correlation.

Step6: Analyze data set 6

The correlation coefficient is positive (not given in the image but from the context of the problem and the trend line concept, and similar to other positive - trend cases here), and if we assume a reasonable positive value close to 1 for a well - behaved trend line, it is strong positive correlation.

Answer:

1. Positive
2. No
3. Positive
4. Weak Positive
5. Strong Positive
6. Strong Positive