Question

For workers on an assembly line the number of weeks on the line, the explanatory variable, and the number of rejects (unacceptable assemblies), the response variable, were recorded during a typical month of work. It was found that the correlation coefficient between the variables was r = -0.61. On the average, does the number of rejects increase, decrease or stay the same as the number of weeks on the line increases?

Answer choices A Stays the same B Increases C Decreases

Answer 1

Given :

correlation coefficient between the variables , r = - 0.61

since the correlation coefficient is negative , the two variables move in opposite direction .

A negative correlation means that there is an inverse relationship between two variables.

That is , as one variable increases other variable decreases.

Similarly if one variable decreases other varible increases.

Therefore , On the average , the number of rejects Decreases as the the number of weeks on the line increases.

So the correct answer choice is C Decreases