Statistics Chapter 2

equation for area of pie chart and total frequency

area of pie chart = total frequency

how to draw a pie chart

total frequency

calculate angle for each frequency (360/frequency)

how to work out radius in comparative pie charts?

what is the purpose of population pyramids?

shows distribution of ages in a population, in numbers or proportion/percentages

how to calculate frequency density?

what does a positive skew look like?

what does a symmetrical (no skew) look like?

what does a negative skew look like?

what are types of misleading diagrams?

3D charts distort diagram parts- difficult to read values.

colours make parts of diagram stand out more when not significant

Lines too thick- difficult to read

what axes and scales can be misleading?

Scales that do not start at zero.

Missing values on scales.

Axes unevenly scaled.

Axes not labelled.

Not using a key.

what is a two-way table?

information in two categories and has two variables so it is bivariate data

what is the function of tables?

gives exact values

does not show trends

what is the function of a bar chart?

for categorical and discrete data

shows trends

what is the function of a line graph

time series

shows trends

best when presenting 5+ data points

what is the function of histograms?

continuous data

proportions area to frequency

does not show frequency

what is the function of a pie chart?

shows proportions

summarises results

no accurate values

equation for calculating lower quartile?

n/4

equation for calculating upper quartile

3n/4

what is an outlier?