Descriptive statistics

• What is a descriptive statistic?

  • expresses numbers in a way that gives us impressions and an overall pattern of results.
• How can descriptive statistics be done?

  • spread/dispersion = range of data
  • averages of the data = mean,mode,median
  • graphs and tables = visual summary of the data
• what’s a mean?

  • average of a set of scores
  • it includes all data=sensitive
• What are strengths and weaknesses of means?

  strengths = only average to include all data

  weaknesses = Mean is distorted by extreme scores reducing representative nurse of the data.
• what is a median?

  • middle score of the data
  • used instead of the mean if there is extreme scores in the data.
• What are strengths and weaknesses of medians?

  strengths = Not affected by extreme scores as the scores are put in order.

  weaknesses = Less sensitive compared to the mean.
• What is a mode?

  The mode is the value that appears most frequently in a data set.
• What are the strengths and weaknesses of the mode?

  weaknesses = Unrepresentative of data.

  strengths = Very easy to calculate.
• what’s a bar chart?

  • known as discrete data
  • used when these categories
  • bars kept separate
• what’s a scattergram?

  • plotting data onto graphs
  • correlations
• what’s a histogram?

  • bars touch each other
• what’s a line graph?

  • IV on the x-axis
  • DV on the y-axis
• What is distribution normal?

  • a Symmetrical spread of frequency date of the forms of bell shaped pattern.
• What is distribution positive skew?

  • spread A frequency data that is not symmetrical where the data clusters at one and.