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Frequencies Tables - Example

 

Data

Subjects were students in grades 4-6 from three school districts in Ingham and Clinton Counties, Michigan. Chase and Dummer stratified their sample, selecting students from urban, suburban, and rural school districts with approximately 1/3 of their sample coming from each district. Students indicated whether good grades, athletic ability, or popularity was most important to them. They also ranked four factors: grades, sports, looks, and money, in order of their importance for popularity. The questionnaire also asked for gender, grade level, and other demographic information.

Source: http://lib.stat.cmu.edu/DASL/Datafiles/PopularKids.html

 

 

Analysis

  1. Open the DataBook summary.vstz
    open this data file via the Help / Open Examples menu; it is in the Sample Data
  2. Select the sheet PopularKids
  3. Choose the menu Analyze and the command FREQ Tables, under group Data Summaries
  4. In Variables, select Gender, Race, Urban/Rural, and School
  5. Click OK

 

 

Output

By default, R code is printed after parsing and before evaluation.
You can avoid this in File / Option / Advanced menu.

DataSheet is converted to DataFrame, in the form DataBook.DataSheet

> .Table <- table(summary.PopularKids$Gender, useNA = "ifany")
> .Table  # counts for Gender

 boy girl 
 227  251 

> round(100*.Table/sum(.Table), 2)  # percentages for Gender

  boy  girl 
47.49 52.51 

> .Table <- table(summary.PopularKids$Race, useNA = "ifany")
> .Table  # counts for Race

Other White 
   36   442 

> round(100*.Table/sum(.Table), 2)  # percentages for Race

Other White 
 7.53 92.47 

> .Table <- table(summary.PopularKids$Urban.Rural, useNA = "ifany")
> .Table  # counts for Urban.Rural

   Rural Suburban    Urban 
     149      151      178 

> round(100*.Table/sum(.Table), 2)  # percentages for Urban.Rural

   Rural Suburban    Urban 
   31.17    31.59    37.24 

> .Table <- table(summary.PopularKids$School, useNA = "ifany")
> .Table  # counts for School

Brentwood Elementary     Brentwood Middle         Brown Middle 
                  67                   84                   52 
                 Elm                 Main              Portage 
                  21                   68                   61 
               Ridge                 Sand      Westdale Middle 
                  48                   28                   49 

> round(100*.Table/sum(.Table), 2)  # percentages for School

Brentwood Elementary     Brentwood Middle         Brown Middle 
               14.02                17.57                10.88 
                 Elm                 Main              Portage 
                4.39                14.23                12.76 
               Ridge                 Sand      Westdale Middle 
               10.04                 5.86                10.25 

> remove(.Table)

 

 

Results

From the output, you might learn that 37.2% of students are urban, 31.6% are suburban, and 31.2% are rural.

 

Resource