Below are four bivariate data sets and the scatter plot for

Below are four bivariate data sets and the scatter plot for each. (Note that each scatter plot is displayed on the same scale.) Each data set is made up of sample values drawn from a population.

Answer the following questions. The same response may be the correct answer for more than one question.

1. Which data set has an apparent positive, but not perfect, linear relationship between its two variables?

Choose one( the x, y data set, the u, v data set, the w, t data set, the m, n data set, none of the data sets)

2. Which data set indicates a perfect positive linear relationship between its two variables?

Choose one( the x, y data set, the u, v data set, the w, t data set, the m, n data setnone of the data sets)

3. Which data set indicates the strongest negative linear relationship between its two variables?

Choose one( the x, y data set, the u, v data set, the w, t data set, the m, n data set)

4. In which data set is there evidence of a strong nonlinear relationship between the two variables?

Choose one (the x, y data set, the u, v data set, the w, t data set, the m, n data set, none of the data sets)

Solution

1 ) data set ( u, v) and (m, n) show +ve linear relationship.

However in data set ( u, v) the change between two consecutive y values is not same for 1 unit change

in x

So, (u, v) apparent positive, but not perfect,

2) data set (m,n) we can see that for 1 unit change in x the y vlue changes by 1 unit:

10, 9 , 8 , 7 -----

(m ,n ) indicates a perfect positive linear relationship between its two variables

3) In None of the data sets there is contnous decrease in y values

4) From the data sets ( x, y) and (w, t) , the scatter plots indicate the (x, y) has more non linearity