PSYCH101 Lecture Notes - Lecture 14: Skewness, Sampling Error, Standard Deviation

• School: University of Waterloo
• Department: Psychology
• Course: PSYCH101
• Professor: Paul Wehr

Document Summary

Psych 101 research methods in behavioural science wednesday feb 3rd. Median: middle score; best measure if there are outliers (extreme scores). Mean: arithmetic mean; most frequently used measure because sampling error is lowest. Mode: most frequently observed score; used for qualitative data. Clothing factory- how big is a typical person, their size. But everyone has a different size, not everyone is typical. If the(cid:396)e"s lots of (cid:448)a(cid:396)ia(cid:271)ility, it (cid:373)ea(cid:374)s that the(cid:396)e is a lot of variability, if small space, not a lot of variability. Median- odd (cid:374)u(cid:373)(cid:271)e(cid:396) it"s easie(cid:396), just the (cid:373)iddle (cid:374)u(cid:373)(cid:271)e(cid:396) Median: 50% of scores fall below, 50% above. Mode: what is observed most often, can have more than one (bimodal) Mean: add up all the scores and divide by the total number of categories. Problem when there is an even number of scores- need to find the 3rd and 4th score and find the midpoint between them.