Reliability Analysis

Lecture

While reliability is concerned with the accuracy of the actual measuring instrument or procedure, validity is concerned with the study's success at measuring what the researchers set out to measure. 

Types of reliability:

• Reliability across time
  Test-retest reliability
  Alternate forms reliability
  These estimates of reliability involve two administrations of the scale
  Can be viewed as the consistency of the scale 
• Internal consistency 
  Split-half reliability 
  Cronbach's coefficient Alpha
  Inter-scorer reliability: correlation of scores between two or more raters who rate the same item, scale or instrument. 
  These methods only involve one adminstration. 

1. Test-retest reliability:
The consistency of your measurement, or the degree to which an instrument measures the same way each time it is used under the same conditions with the same participants. 

Procedure:

• adminster your scale at two seperate times for each pp
• compute the…