D4 - Represnting Data Diagrammatically

Question 1

Pictogram

Answer 1

Advantages
>Data is easily counted and represented using symbols. Often qualitative data.

Disadvantages
>Difficult to portray fractions

Question 2

Bar Chart

Answer 2

Advantages
>Good for comparing data in different categories, easily understood

Disadvantages
>Show the number of items, but not their actual values

Question 3

Pie Chart

Answer 3

Advantages
>Good visual representation of the proportions. Often used with qualitative data

Disadvantages
>Individual data is lost - not really suitable if there are many categories

Question 4

Scatter Graph

Answer 4

Advantages
>Used to determine correlation between two variables

Disadvantages
>Time consuming to draw

Question 5

Stem and Leaf diagrams

Answer 5

These are simple diagrams that are good for comparing small amounts of data. The data is not lost.
They are not really appropriate if there is a lot of data as the appearance can be off-putting.

Question 6

Box and Whisker plots

Answer 6

Make it fairly easy to find quartiles and IQR. Good for comparing two data sets and summarising data.
The individual data is lost and the mean and mode are not identifiable.

Question 7

Cumulative Frequency graph

Answer 7

These are used when grouped data is given.
So, the individual data is lost.
Easy to find percentiles and quartiles.

Question 8

Histograms

Answer 8

Histograms are used especially when grouped continuous data is give, more so when the group intervals are not all the same.
Area=frequency
Frequency density = the number of items in a given unit.