A scatter diagram in which most of the points fell on a horizontal line across the range of the diagram would be expected to have a correlation coefficient indicating:

A scatter diagram in which most of the points fell on a horizontal line across the range of the diagram would be expected to have a correlation coefficient indicating:

• A. A high positive correlation
• B. A high negative correlation
• C. A correlation coefficient near zero
• D. A perfect correlation

Answer: (C)

This item tests how to interpret the correlation coefficient from a scatter plot. Correlation measures how two variables move together along a straight line. When most points lie on a horizontal line, the y value stays essentially the same as x changes, so there is no linear tendency for y to increase or decrease with x. That means the data show little to no linear relationship, and the correlation coefficient is near zero. A high positive or high negative correlation would require a clear upward or downward trend, and a perfect correlation would require all points lying exactly on a single straight line with no scatter. (If one variable has no variation at all, the correlation is technically undefined, but with a mostly horizontal pattern, the practical takeaway is near zero.)

This item tests how to interpret the correlation coefficient from a scatter plot. Correlation measures how two variables move together along a straight line. When most points lie on a horizontal line, the y value stays essentially the same as x changes, so there is no linear tendency for y to increase or decrease with x. That means the data show little to no linear relationship, and the correlation coefficient is near zero. A high positive or high negative correlation would require a clear upward or downward trend, and a perfect correlation would require all points lying exactly on a single straight line with no scatter. (If one variable has no variation at all, the correlation is technically undefined, but with a mostly horizontal pattern, the practical takeaway is near zero.)