PS296 Lecture Notes - Lecture 1: Count Data, Statistical Parameter, Categorical Variable
Document Summary
Types of data: categorical data( frequency data, count data)- data representing counts or number of observations in each category, measurement data (quantitative data)- data obtained by measuring objects or events. Interval scale- scale on which equal intervals between objects represent equal differences-differences are meaningful: ratio scale- scale with a true zero point- ratios are meaningful. Properties of scales of measurement: nominal- identity, ordinal- identity, magnitude/order, ratio- identity, magnitude/order, equal intervals, actual measurement of 0. Displays of data: frequency distribution: a distribution in which the values of the dependent variable are tabled or plotted against their frequency of occurrence. Frequency tables: frequency table for a categorical variable, usually nominal or ordinal data, how many males, how many females in a class. Graphical representations of data: we can describe set of numbers in pictorial form, graphical presentation to demonstrate data, describe what occurred, frequency of each score.
