PSYC 3170 Lecture Notes - Lecture 7: Standard Deviation, Unimodality, Standard Error

• School: University of Guelph
• Department: Psychology
• Course: PSYC 3170
• Professor: Masood Zangeneh

Document Summary

Chapter #6 the normal curve, standardization, and z-scores. It is a mathematically defined, bell shaped curve that is unimodal and symmetric. The size of a sample approaches the size of the population the distribution resembles a normal curve. Standardization is a way to convert individual scores from different normal distributions to shared normal distribution with a known mean, standard deviation, and percentiles. A way to create meaningful comparisons between observations from different distributions. It can be done by transforming raw scores from different distributions into z-scores, also know as standardized scores. z-scores is the number of standard deviations a particular score is from the mean. The z-score give us the ability to convert any variable to a standard distribution, allowing us to make comparisons among variables. A desire to make meaningful comparisons forces us to convert raw scores into standardized scores. Give us a sense of where a score falls in relation to the mean of its population.