help with this scatterplot equation

Question

3. For the table that follows, answer the following questions:

x	y
1	-1/2
2	-1
3	-3/2
4

 
 
 
 
 




-  Would the correlation between x and y in the table above be positive or negative?
 
-  Find the missing value of y in the table.
 
-  How would the values of this table be interpreted in terms of linear regression?
 
-  If a "line of best fit" is placed among these points plotted on a coordinate system, would the slope of this line be positive or negative?

Answer 1

The relationship between x and y seems to be y=-½x. The missing y is -2. The correlation is negative because y decreases as x increases. The slope is negative (-½). The interpretation would be a perfect correlation (perfect linear regression) between x and y because all point line on the line. The correlation coefficient would be -1. (A coefficient of about 0 would suggest no correlation.)