Just a few sentences for discussion and reply to Lachell in 3-4 sentences
Discuss each of the different type of validity as it applies to a measurement instrument such as the Perceived Stress Scale
Discuss each of the different type of validity as it applies to a measurement instrument such as the Perceived Stress Scale (http://www.psy.cmu.edu/~scohen/PSS.html). Discuss the face validity and the construct validity of this measure.