tables & graphs

• raw data tables

  Shows scores before analysis.

  -does not tell us much as it is hard to identify patterns in data.
• frequency data tables

  Data can be organised and patterns can be seen.

  -more useful than raw data tables.
• summary tables

  Summary tables are used when displaying the measures of central tendency and measures of dispersion.

  -shows a clear summary of data.
• pie charts

  Data is in categories - 'discrete data'.

  Used for nominal data.
• bar charts

  'discrete data' - categories are placed on the X axis, frequency/mean is placed on the Y axis.

  -bars should not touch. All bars should be separated equally + have equal width.

  Used for nominal data.
• histograms

  Represents data on a 'continuous scale' - plot the frequency.

  -columns touch as all data is on a related scale. Scores are on the X axis, the other variable is on the Y axis.

  Used for interval data.
• frequency polygons

  An alternative to a histogram (frequency polygons are also called line charts).

  -the lines show where mid-points of each column on a histogram would reach.

  -useful in comparing 2+ conditions at the same time.

  Used for interval data.
• Scattergrams

  Measures the relationship between 2 variables.

  -one variable on the X axis, the other variable on the Y axis.

  -plot an X on the graph where variables meet.

  -the patterns of point reveal different types of correlation (positive, negative, no relationship).

  Used for correlations only.