Ugrás a tartalomhoz

SOCIAL STATISTICS

Renáta Németh, Dávid Simon

ELTE

4. fejezet - Lecture 4

4. fejezet - Lecture 4

Topics

  • Graphic presentation

    • Pie chart

    • Bar chart

    • Histogram

    • Frequency polygon

    • Stem-and-leaf plot

    • Statistical map

    • Time series chart

  • How to lie with graphic presentations?

Motivation

Data are more easily readable and understandable when presented graphically

Pie chart

Appropriate for nominal and ordinal variables (small number of categories)

ISSP 2006, Hungary. Worktype, a nominal variable. Frequency distribution:

Frequency

Percentage

Public sector

468

51.0%

Private sector

396

43.1%

Self employed

54

5.9%

Total

918

100%

More easily understandable:

n_pic_5

Exploding out a single slice of the chart is a way to emphasize a piece of information. Interpret the pair of pie charts below.

n_pic_6

While the corresponding percentage distributions are less expressive:

Hungary

USA

  

Frequency

Percentage

Frequency

Percentage

Public sector

468

51.0%

281

19.5%

Private sector

396

43.1%

985

68.3%

Self employed

54

5.9%

177

12.3%

Total

918

100%

1443

100%