PSYC 2001 Lecture Notes - Lecture 7: Internal Validity, External Validity, Type I And Type Ii Errors

• School: Carleton University
• Department: Psychology
• Course: PSYC 2001
• Professor: Deanna Whelan

Document Summary

Lecture 7: quality of the measures and manipulations, ex. Issue would be: measuring intelligence by measuring distance between shoulder and fingertip: statistical, statistical conclusions are appropriate and reasonable. Internal: no alternative causal explanations for the outcome, ex. Interrogating frequency claims: construct validity of the variable. How well was the variable measured: external validity is essential! Can we generalize from the sample to the population: statistical validity. Working memory average is seven, but means most people are 5-9. Interrogating association claims: construct validity of each variable. How well was each variable measured: statistical validity. Is it statistically significant? (type i and type ii errors: external validity. To whom or what can we generalize the association: may be less important to the researcher. Our conclusions based on research are not 100% correct: two types of errors. Type ii (false negative or miss pregnant female being told not-pregnant) In the medical community, type ii is obviously worse.