PSY 121 Chapter Notes - Chapter 12: Pie Chart, Bar Chart, Frequency Distribution
Document Summary
Statistics helps us understand the data collected in research investigations in two fundamental ways. First, statistics are used to describe the data. Second, statistics are used to make inferences and draw conclusions, on the basis of sample data, about a population. Whenever a variable is studied, the researcher must create an operational definition of the variable and devise two or more levels of the variable. The levels of the variable can be described using one of four scales of measurement: nominal, ordinal, interval, and ratio. The scale used determines the types of statistics that are appropriate when the results of a study are analyzed. Also recall that the meaning of a particular score on a variable depends on which type of scale was used when the variable was measured or manipulated. The levels of nominal scale variables have no numerical, quantitative properties. The levels are simply different categories or groups. Most independent variables in experiments are nominal.
