Graphical Skills Flashcards
What does a polar graph/ rose diagram show?
Shows direction as well as magnitude
How can you construct a polar graph?
Using a compass and a protractor, draw in lines that correspond to the compass directions
Draw a scale - scale relates to the radius of the diagram, e.g 1cm can represent 10 cars - Circles are drawn at 1cm radius
Mark the scale on the vertical axis
Plot the data
What are the advantages and disadvantages of a rose diagram?
Gives a good visual representation of the data
Shows trends in terms of direction and volume
They do not show the exact route taken
Care is needed when deciding upon a scale where there is a large range of values
What are the advantages of a bar graph?
Shows relationship between 2 or more variables
Show proportions and are visually attractive
Simple to construct
What are the disadvantages of a bar graph?
If wide range of data impact lost as it is difficult to read accurately
Plotting too many bars makes it appear cluttered
When should you use a bar graph?
When looking at quantities of particular variables and how they change over time
What are the advantages of a line graph?
Shows absolute changes in data
Key and colour coding can be used for greater visual effectiveness
What are the disadvantages of a line graph?
Too many lines can lead to difficult interpretation
Awkward scales can distort the visual effectiveness
When should you use a line graph?
When wanting to investigate the relationship between two or more variables
Looking for positive, negative or no correlation
What are the advantages of a scattergraph?
Used when data available for many locations
Shows anomalies
Can identify patterns and trends and show relationships between 2 variables
What are the disadvantages of a scattergraph?
Only allows for the relationship between 2 variables to be displayed
Too much data can be difficult to read
Correlation can emerge even when a relationship is only coincidental
When should you use a scattergraph?
When looking to investigate the type of correlation between 2 variables
Used to represent and compare 2 sets of data
What are the advantages of a pie chart?
Visually effective
Easy to read and understand
Shows relative contribution of each segment to the whole 100%
What are the disadvantages of a pie chart?
Difficult to make comparisons between pie charts where there are lots of segments
It many segments a similar size; it is hard to interpret
When should you use a pie chart?
When comparing quantities/percentages of data
What are the advantages of a dispersion diagram?
The data range is easily identifiable
Clustering can be seen clearly
Box/Whisker plots can be added to further analyse data, which increases geographical understanding
What are the advantages of a dispersion diagram?
The data range is easily identifiable
Clustering can be seen clearly
Box/Whisker plots can be added to further analyse data, which increases geographical understanding
What are the disadvantages of a dispersion diagram?
Doesn’t show a causative relationship as only one variable is plotted
No key used, so doesn’t allow for investigation of data over time/space
When should you use a dispersion diagram?
Allows you to investigate visually the spread of a set of data
What are the advantages of a triangular graph?
Very useful if three components are to be compared
Dominant variable can be seen
After plotting, clusters emerge which enables identifying trends
What are the disadvantages of a triangular graph?
Hard to interpret
Limited range of data can be used
Must be broken down into 3 components expressed as percentages
Cannot be used for absolute data
When should you use a triangluar graph?
When investigating data that has three components - e.g occupation in the primary, secondary or tertiary sector
Position of dot indicates the dominance of each of the three components making patterns easy to identify
What are the advantages of a population pyramaid?
Clear shows the population structure of a country
Gives accurate data
What are the disadvantages of a population pyramid?
Can be difficult to contruct
