PSYC 412 Lecture Notes - Lecture 2: Statistical Inference, Descriptive Statistics, Standard Deviation

• School: McGill University
• Department: Psychology
• Course: PSYC 412
• Professor: Melanie Dirks

Document Summary

Lecture 2: stats for success in psyc412: what are inferential statistics and why do we even need to use them anyway, descriptive statistics, describe a data set (1) central tendency. Standard deviation: they do not allow you to say anything about people who were not included in your data set. I want to know the average gpa of u3 psych majors. So, i ask 20 people: sample vs. population. Population is the group i am interested in. I want to know if u3 psych majors at mcgill have higher gpas than. If i obtain the gpa of every single u3 econ and psych major, i can compare the means. If i obtain the gpa of a subset of u3 econ and psych majors, i can"t just compare the means. Inferential statistics: sample 20 u3 psych majors and 20 u3 econ majors, psych majors mean gpa is 3. 0, econ majors mean gpa is 2. 5.