List

Box Plot

Box Plot is a graphical tool used to display the characteristics of data distributions, particularly suitable for describing the central tendency and dispersion of data. SPSSAU supports:

Batch analyze 'titles'.

Generate box plots with up to 2 grouping variables (e.g., gender, education).

Display specific outlier values and the count of outliers.

Calculation Steps

Box plots involve the calculation of five metrics: the minimum, the 25th percentile, the median, the 75th percentile, and the maximum, along with the criteria for identifying outliers, as follows:

  • IQR: IQR = Q3 - Q1
  • Minimum Value = Q1 - 1.5 × IQR
  • Maximum Value = Q3 + 1.5 × IQR
  • &nspb;
  • Q1 represents the 25th percentile.
  • Q3 represents the 75th percentile.
  • IQR represents the interquartile range, which indicates the middle 50% range of the data.

Note:

The minimum value is not necessarily the smallest value, and the maximum value is not necessarily the largest value. The criteria for identifying outliers are as follows: values smaller than the minimum value or greater than the maximum value.

Data Format

The data includes two Categories and the analysis data (Categories can be omitted during analysis).