The 25 Item "Parenting Hassles Scale" Asks Parents Questions About

Short Answer

The 25 item "Parenting Hassles Scale" asks parents questions about certain situations in their family. They are asked to rate these situations on (1) how often they occur (frequency), and (2) how much they bother them (intensity). The score system for the frequency was 0-4 points (0 = never, 4 = all the time) and for the intensity 1-5 (1 = not much at all, 5 = very much). If an item received a 0 (zero) for frequency, it automatically received a 0 (zero) for intensity. The two variables, frequency and intensity, were formed by taking the total of the corresponding scores from the two rating scales across the various situations These two variables are then used to create a scatterplot. The symbols indicate whether a mother, a father, or a step parent filled in the questionnaire.
Based on the scatterplot, what is the problem with using one regression equation for all parents combined?