HDE 12 Lecture Notes - Lecture 5: Descriptive Statistics, Scatter Plot, Central Tendency
29 Nov 2017
School
Department
Course
Professor
Document Summary
Descriptive statistics: used to organize and summarize the properties of a set of data. Frequency distributions and scatterplots are techniques for organizing a column of data in a data matrix. Frequency distributions: table that gives visual picture of observations on particular variable. Frequency histogram: possible exam scores on x-axis, frequency on y-axis. Stem and leaf plot: values on the left, aka the stems, values on the right aka the leaves. Central tendency: measure of what value the individual scores tend to center on. Median: value at the middle most score of the distribution of scores. Mean aka average: add up scores, divide up by number of scores: most common measure of central tendency. Standard deviation sd: captures how far on average score from the mean. Large sd means more variability in set; scores spread out from mean. Small sd means less variability, scores are more clustered around mean.
