Skills Flashcards
What are the cartographic skills?
- Atlas maps
- Base maps
- Sketch maps
- Maps with located proportional symbols
- Maps showing movement - flow lines, desire lines and trip lines
- Choropleth maps
- Isoline maps
- Dot maps
- Weather maps
- Detailed town centre plans
What are the graphical skills?
- Line graphs
- Bar graphs
- Pie charts and proportional divided circles
- Triangular graphs
- Radial diagrams
- Logarithmic scales
- Dispersion diagrams
- kite diagrams
What are the ICT skills?
- remotely sensed data
- use of databases
- GIS
What are the statistical skills?
- Measures of central tendency
- Measures of dispersion - quartiles - standard deviation
- Spearman’s rank correlation test
- Chi-squared
- Mann Whitney
Sketch maps
used when rough map of a site is needed
A- good memory tool especially if accompanied by annotations
D - may not be accurate, not to scale, difficult to decide what to include
Maps with located proportional symbols
the size of a circle/ symbol shows the population of data often for one area
A - very visual, can represent a large range of data, not dependant on the size of the area
D - difficult to produce, not accurate cant extract exact data, overlap can occur making it hard to read or interpret
Maps showing movement - Flow lines, desire lines, trip lines
Flow lines - Width of the arrow represents a flow rate also which direction the flow is moving, often used for river discharge.
Trip lines - shows where a population has visited
Desire lines - shows were a population moves from one area to another
A - immediate impression, visual, can show movements easily, desire lines show trends in migration, clear sense of direction, clear location component
D - hard to draw, flows can overlap, may be difficult to show meeting point of the wide bands without overwhelming the map
Choropleth map
Use colour overlap over a map to show how an area fits into a range of values, often with darker values representing the higher values and the lighter for the lower values
A - gives general impression, visual impression of change over a space, anomalies can be identified, easily done by hand or on computer, doesn’t breach data protection, good for data which involves density reading, easy to interpret via key
D - general, false impression of abrupt changes at boundaries, variations in each are hidden, reading exact figures is impossible
Isopleth map
lines joining data of equal values, data point on a map are joined up with data points of equal values
A - drawn easily on computers, can see areas of equal value, can see gradual changes, avoids problems of boundary lines
D - don’t show discontinuous data distributions, only work where there is plenty of data spread over the study area and the changes are gradual, small lines and numbers on graphs can be difficult to read
Dot maps
shows distribution of data over an area
A - effective in showing spatial density, shows variation and pattern, easy to interpret, purpose is easily understood, easy to generate on a computer
D - actual values cant be seen, dots get crowded, not very accurate, confusing if done by hand, small areas aren’t represented accurately, easy to make a mistake or be subjective
Line graphs and bar graphs
Line shows continuous data or a trend line
Bar -Height of block gives frequency, data must be placed in even or artificial categories
A - little background knowledge needed to understand graphs, comparisons can be easily made with other similar graphs or more than one line on one graph, anomalies are quite clear, give visual image trend and correlation, can plot the standard deviation, bar charts show cumulative data which is common, line graphs use continuous data which is common
Pie charts and proportional divided circles
out of 100% these show a breakup of data into percentage of the total which is then shown by segments on the pie chart
A - allow fractional and percentage comparison, display approximate proportions of variables throughout the area taken up by the pie chart, can see general trend
D - cant use for exact comparisons, impossible to extract specific data, cant represent more than one point at a time, may not always be accurate, overlaps can cause issues if they are used on maps
Triangular graphs
This allows three proportional variables out of 100% to be plotted against each other
A - easy to compare, 3 bits of data can be compared at the same time as they use the same scale, by using a lot of graphs comparisons can be made
D - difficult to construct, may be wrongly interpreted, quite difficult to read, have to have background knowledge of how to use, confusion over which is which
Radial diagrams
Shows how a variable changes due to an independent variable
A - can compare multiple sets of data, lots of data can be put on one graph, visual, individual variables can be compared
D - No stats test can be linked, hard to spot anomalies, hard to make a suitable scale
Logarithmic scales
A - lots of data with a large range can be plotted, smaller values are given greater priority due to logarithmic nature, can be semi-logarithmic or both, variables of very different sizes can be plotted on the same graph, show progression and can draw comparisons from different sources, can show previously unseen patterns
D - cant start from 0, may make relations appear different
