measures of central tendency

• measures of central tendency

  • provide a single number of value that describes a set of raw scores or data values
  • 3 commonly used descriptive statistics: mean, mode, median
• mean

  • takes into account all scores in a data set
  • sensitive statistic
  • disadvantage - if one value is incredibly high or low the overall mean can be very distorted
• median 


  • central value in a set of values
  • calculated by putting all values in a set order from lowest to highest then identifying the middle number
  • not distorted by very high or low values
  • usually less precise than the mean
• mode 


  • value which occurs most
  • most suitable measure of central tendency for nominal data
  • rarely useful when the set of data contains a small number of values