Exam 1

1. Metainformation

   Tag	Value
   file	Reliability_eur-reliability-102-en_eur-reliability-102-en
   name	eur-reliability-102-en
   section	Reliability/Analysis/Test-retest
   type	num
   solution	0.843
   tolerance	0.005
   Type	Calculation
   Program	Calculator
   Language	English
   Level	Statistical Literacy

   Question

   Below you can find the observed scores on a depression scale with a one‐week interval.High scores indicate high levels of depression.

   Participant	Form1	Form2
   1	17	19
   2	21	23
   3	14	11
   4	28	24
   5	32	34
   6	24	21

   Calculate the test‐retest reliability. To decrease your work: $s^2_{1st} = 37.06$, $s^2_{2nd} = 54.56$ and $c_{1st,2nd} = 37.89$.

   
   

   Solution

   The test‐retest reliability is equal to the correlation between the two scores on the two administrations. This correlation is: $r_{F1,F2}$ = $\frac{37.89}{\sqrt{37.06 \times 54.56}} = .843$.