Presentation of quantitative date

Question 1

Tables

Answer 1

• When a table appears in the results section they aren’t raw scores but have converted to descriptive stats
• Standard practice to write a summary paragraph under a table which explains the results and draws conclusions

Question 2

Bar chart

Answer 2

• Represented usually using a suitable graphical display
• easily shows the difference in mean
• used for discrete data
• the different bars show different conditions

Question 3

Histograms

Answer 3

• the bars touch eachother
• x-axis is continuous
• x-axis has even sized intervals

Question 4

Scattergrams

Answer 4

• don’t depict differences but instead associations between co-variables
• there is one variable on each axis

Question 5

Normal distribution

Answer 5

• E.g. If you measured the height of everyone in the school, the frequency should form a bell shaped curve
• symmetrical
• most peoples values are located in the middle pf the curve with much fewer people on the extreme ends
• the ‘tails’ of the curve never reach the bottom of the axis as more extreme scores may be theoretically possible

Question 6

Skewed distribution

Answer 6

• not all distribution is symmetrical
• skewed distribution leans to one side
• positive skew = most of the distribution is to the left, and the long tail is on the right (e.g on a test where most people did really badly)
• when positive, the mean is pulled to the right a lot but the mode stays similar
• Negative skew = bulk of the scores on the right which mean the long tail is on the left (mean pulled to the left)