PSYC 1000 Lecture Notes - Lecture 4: Statistical Inference, Standard Deviation, Effect Size

• School: University of Guelph
• Department: Psychology
• Course: PSYC 1000
• Professor: Lisa Giguere

Document Summary

Median: of observations fall on each side. Range: difference between highest and lowest scores in a distribution. Standard deviation: calculation of the average distance of scores from the mean. Describes distribution of many types of data. Statistical inference allows us to assess if the result could have been caused by random/chance variation between groups. Typically researchers use 5% as a criteria. They can either accept or reject hypothesis (if effect of iv on dv is statistically significant, data supports hypothesis. If not, data does not support hypothesis, must review theory) Effect size: allows us to determine if the change in dv explained by iv is small or large. Iv could have a statistically significant effect on dv, but that does not mean it is large. Eg: peer-viewed article reporting on effect of a new therapy on depression. Eg: hearing about this theory from cosmo.