The graph below is from Wright and London (2009). Which of the following descriptions best applies to this graph:
A)Fixed slopes, fixed intercepts
B)Fixed slopes, random intercepts
C)Random slopes, random intercepts
D)Random slopes, fixed intercepts

Question

The graph below is from Wright and London (2009). Which of the following descriptions best applies to this graph: 
A)Fixed slopes, fixed intercepts 
B)Fixed slopes, random intercepts 
C)Random slopes, random intercepts 
D)Random slopes, fixed intercepts

Quizplus · Accepted Answer

The graph shows individual growth trajectories (lines) for different subjects over time (x-axis). The fact that the lines have different slopes suggests that there are random slopes, meaning that the rate of change over time varies between individuals. Additionally, the fact that the lines do not start at the same point on the y-axis suggests that there are random intercepts, meaning that the initial values at time 0 (or some other starting point) also vary between individuals. Therefore, the best choice is C, which represents random slopes and random intercepts.

The Graph Below Is from Wright and London (2009)