2. FREQUENCY DISTRIBUTIONS raw score distribution: list of each individual’s score frequency distribution: list of each score that appears and how many times each score occurs

3. Uses of Frequency Distributions Summarize a large set of data. Describe the shape of a distribution. Needed for inferential statistics.

4. A Raw Score Distribution 7531723526623477531426145724342211355324235144213575317235266234775314261457243422113553242351442135

5. Frequency Distribution Table xf 75 63 58 48 39 210 17

6. Frequency Polygon Best for quantitative/continuous data. Study Time in Hours f 0123401234 5 10 15

7. Histogram Best for quantitative/continuous data. Study Time in Hours f 0 1 2 3 4 5 10 15

8. Bar Graph Best for qualitative/discrete variables. f Ed. Bus. A&S AST 5 10 15 College

9. Guidelines for Graphs Label units. Make axes proportional (y axis should be 2/3 to 3/4 length of x axis). Make bars equal width. Keep it simple.

10. Describing Frequency Distributions symmetrical: same on both sides

11. skewed: scores piled on one side positive skew negative skew body tail

12. kurtosis: steepness leptokurtic platykurtic mesokurtic

13. Frequency Distribution Statistics relative frequency: proportion of scores that are x cumulative frequency: number of scores up to and including x percentile rank: percentage of scores up to and including x percentile: x score at a percentile rank

14. Cumulative Frequency xfcf 7550 6345 5842 4834 3926 21017 177 start at the bottom score add the frequencies always equals N, total # of scores

15. Relative Frequency xfrf 75.10 63.06 58.16 48.16 39.18 210. 20 17.14 divide each frequency by N 5/50 =.10 3/50 =.06 8/50 =.16 9/50 =.18 10/50 =.20 7/50 =.14

16. Percentile Rank xfcfpr 7550100 634590 584284 483468 392652 2101734 17714 divide cf by N and multiply by 100 100th %ile = 7 90th %ile = 6 84th %ile = 5 68th %ile = 4 52nd %ile = 3 34th %ile = 2 14th %ile = 1