Corelation and Regression

may be used to predict a value of y if the corresponding x value is given

is evidence for a cause-effect relationship between x and y

can only be computed if a strong linear relationship exists between x and y

None of these alternatives is correct.

Between income and expenditure on education

Between price increase and demand for a certain product

Between average number of hours studied per day and the performance of the students in the examination

Between advertising expenditure and sales of a product.

Area of a circle is in definite constant relationship with radius

When area of the circle is ½ radius

None of these

All of these

increase by 34%

increase by 3.4%

decrease by 0.34%

decrease by 3.4%

Graphic correlation

Scatter diagrams

None of these

Both of these

is the square of the coefficient of determination

is the square root of the coefficient of determination

is the same as r-square

can never be negative

must also be in kilograms

must be in some unit of weight

cannot be in kilograms

can be any units

Reasonably good relationship

Lack of linear relationship

Perfect relationship

None of these

$217,500

222,500

5000

7.25

0.09 above the legal limit

0.0027 below the legal limit

0.0027 above the legal limit

0.0733 above the legal limit