Lecture#3-PSYC 204

Lecture#3-PSYC 204

1. Descriptive Statistics

   • Interval or Ratio Dat: Constructing a Frequency distribution
     • guideline for constructing a f. distribution based on class interval
       • a) divide data into equal, arbitrary intervals (5 to 20)
         • b) choose class intervals (interval width) i.e. 1,2,3,4,5,10 or 20
           • c) appropriate interval size reflects distributional nature of data
     • a) collect data (absolute f. distribution)
       • b) Classifying
         • c) Count Table
   • f. distributions, graphical distributions
   • nominal or ordinal data
     • a) collect data
       • b) classify
         • c)

2. Types of Distribution

   • cumulative f.
     • =Def: total number below a certain value
   • cumulative percentage
     • def:
   • bivariate f. distribution
     • 2 measures per observation

3. Relative Frequency (proportion) or % Frequency (percent)

   • Rel f.
     • express each f. as a proportion
       • formula
   • Percent f.
     • express each f. out of 100