AtlasSession 4L11: Graphical representation of data and measures of associationp.18–21, 25–26
Graphs for quantitative data
- 1 earlier topics
- Data and types of variables
- Distribution of data
- Types of distribution
- Normal vs non-normal
- Graphs for quantitative data
- Next: Scatter plots and correlation
Fig. 1
Fibre diameter of 200 electrospun PCL fibres by SEM (nm)
Fig. 1. A bell-shaped pile of 200 fibres (fibre diameter), highest in the middle at 700 nm and thinning out on both sides; one step of spread is 160 nm. About 3 in 100 fibres are 1000 nm or more.
- Middle
- 700 nm
- One step of spread
- 160 nm
- Fibres of 1000 nm or more
- about 3 in 100
Distribution Lab · First look
Level 1 · First look · Lecture 11 · p.18–21, 25–26
Read a histogram and a box plot, group measurements into bands, and show before/after change.
Read histograms with a normal overlay and boxplots (overall and by group), categorise a quantitative variable at clinical thresholds, and display paired before/after data.
Height bands (the step you are on)
Line people up by height and count each 10 cm band.
Line people up by height and count how many fall in each 10 cm band: the counts make a row of bars. Here each bar counts electrospun fibres in one band of diameter.