PSYCH 100A Lecture Notes - Lecture 4: Standard Deviation, Squared Deviations From The Mean
Document Summary
Bias: sample variability is always smaller than population variability: i. e. car speedometer always shows you are driving 5 mph slower than you are actually going. Ss= (x-)2 is the same computation as for the population. Add the correction the bias in sample variability, denominator becomes n-1. **round mean 2 decimal places when calculating x. Not free to control one of the values in the data set; the others are free to vary (so that the mean stays the same) # of values that used to compute the mean the # of means computed. The two values that we always want to report are the mean and standard deviation. Provides a measure of the typical or standard distance from the mean for a distribution. Allows us to get a concept of how spread out the data are. Common measure to describe a set of data (along with the mean) 68% of individuals in sample within one standard deviation on either side.
