Geographical Skills
LOCATE AND
DIFFERENTIATE
ELEMENTS OF THE
EARTH’S SURFACE
Direction
Latitude and longitude
Grid reference
A model of an A380 at 1:200 scale.
Scale
Maps are often known as large scale or small scale.
A large scale map refers to one which shows greater detail
because the representative fraction (e.g. 1/25,000) is a larger
fraction than a small scale map which would have an RF of
1/250,000 to 1/7,500,000.
Large scale maps will have a RF of 1:50,000 or greater (i.e.
1:10,000). Those between 1:50,000 to 1:250,000 are maps with
an intermediate scale.
Maps of the world are very small scale, about 1 to 100 million.
Maps
Aerial, oblique and
ground-level photography
We can define vertical aerial
photographs as a photo taken from
an aerial platform (either moving or
stationary) wherein the camera axis
at the moment of exposure is truly
vertical.
1. High angle oblique; and
2. Low angle oblique.
In a high angle oblique, the apparent horizon is shown; while in a
low angle oblique the apparent horizon is not shown. Often
because of atmosphere haze or other types of obscuration the true
horizon of a photo cannot really be seen. However we often can
see a horizon in an oblique air photo. This is the apparent horizon.
Satellite imaginery
READ, INTERPRET,
ANALYSE AND PRODUCE
MAPS
Isoline and isopleth maps
Common for mapping surface elevations,
amounts of precipitation, atmospheric
pressure, and numerous other
measurements that can be viewed
statistically as a third dimension.
The third dimension is shown by a series
of lines called isopleths which connect
points of equal value.
Sketch map
sketch map - a map drawn from observation (rather than from
exact measurements) and representing the main features of
an area
Topological maps
Total Elderly
"We live in an era of unprecedented, rapid and
inexorable global ageing."
Dot maps
Proportional symbols
Flow diagrams/charts
Have a key for the number of
cars(vehicles) you have seen and put it in
the form of a line. I.e. Make a big line
represent 10 cars, a smaller line represent
5 cars etc. You can also do this in the
form of measurements, write a
measurement for the thickness of the line.
Then just put the different sized line onto
your map along with the key and you're
done.
A simple flowchart representing a process
for dealing with a broken lamp.
INTERPRET
TOPOGRAPHIC MAPS
WHERE APPROPRIATE TO
THE OPTIONAL THEMES
READ, INTERPRET,
ANALYSE AND
CONSTRUCT GRAPHS
Scatter graphs
Line graphs
Triangular graph
Histograms
A histogram is "a representation of a frequency
distribution by means of rectangles whose
widths represent class intervals and whose
areas are proportional to the corresponding
frequencies."
Pie charts
Advantages
display relative proportions of multiple
classes of data
size of the circle can be made
proportional to the total quantity it
represents
summarize a large data set in visual
form
be visually simpler than other types of
graphs
permit a visual check of the
reasonableness or accuracy of
calculations
require minimal additional explanation
be easily understood due to widespread
use in business and the media
Disadvantages
do not easily reveal exact values
many pie charts may be needed to show
changes over time
fail to reveal key assumptions, causes,
effects, or patterns
be easily manipulated to yield false
impressions
Population pyramids
Compound graphs
Logarithmic graphs
By nature of the logarithm, most log
graphs tend to have the same shape,
looking similar to a square-root
graph:
Logarithmic graph
Lorenz curve
In economics, the Lorenz curve is a graphical representation of the
cumulative distribution function of a probability distribution; it is a graph
showing the proportion of the distribution assumed by the bottom y% of the
values. It is a curve that illustrates income distribution. It is often used to
represent income distribution, where it shows for the bottom x% of
households, what percentage y% of the total income they have. The
percentage of households is plotted on the x-axis, the percentage of income
on the y-axis. It can also be used to show distribution of assets. In such use,
many economists consider it to be a measure of social inequality. It was
developed by Max O. Lorenz in 1905 for representing income distribution.
The concept is useful in studies of biodiversity, where cumulative proportion of
species is plotted against cumulative proportion of individuals.
UNDERTAKE STATISTICAL
CALCULATIONS TO SHOW
PATTERNS AND CHANGES
Totals
An amount obtained by addition.
Averages
mean: the sum of all the members of the list
divided by the number of items in the list.
median is described as the number separating
the higher half of a sample from the lower half.
mode: means the most frequent value
Frequency
In statistics, a frequency distribution
is a list of the values that a variable
takes in a sample. It is usually a list,
ordered by quantity, showing the
number of times each value appears.
Ranges of data
(differences between maximum and minimum)
density
World population density by country in 2006 (choropleth map).
Percentages
What is 13% of 98?
Answer: 13% × 98 = (13 / 100) × 98 = 12.74
Ratios
A ratio is an expression which compares quantities relative to each other.
For example, the ratio 60 metres to 1 second, or 60:1 is written as 60 m/s, or
60 ms−1, "60 metres per second" and is thought of as a measurement of velocity.
Dependency ratio
MANIPULATE AND
INTERPRET DATA USING
QUANTITATIVE
TECHNIQUES
Measures of correlation
Spearman's Rank
Correlation Coefficient (page
41 of Planet Geography) is a further
technique for analysing
this data set.
Spearman's Rank Correlation
Measures of
concentration and
dispersion
Nearest neighbour
Location quotients
Nearest Neighbour
Location Quotient
The Location Quotient is a measure of the
concentration of industry in a region compared to the
national average eg if 15% of manufacturing
employment in a region is in textiles and the national
average for textile employment is only 5% then the LQ
for textiles in this region will be 15/5 or 3. This
means that textile employment in the region is three
times more important than nationally.
LQ =
Number Employed in Industry A in a particular region
Total Employment in the particular region
Divided by
Number Employed in Industry A in the whole country
Total Employment in the country
LQ < 1.0 =
A LQ that is less than zero suggests that local employment is less than was expected for a given
industry.
A LQ = 1.0 =
A LQ that is equal to zero suggests that the local employment is exactly sufficient to meet the
local demand for a given good or service.
A LQ > 1.0
A LQ that is greater than zero provides evidence of basic employment for a given industry. These
extra jobs then must export their goods and services to non-local areas.
Measures of spatial
interactions
Spatial interaction is the flow of products, people, services, or information among
places, in response to localized supply and demand.
Spatial interactions usually include a variety of movements such as travel,
migration, transmission of information, journeys to work or shopping, retailing
activities, or freight distribution.
UNDERTAKE
GEOGRAPHICAL
INVESTIGATION