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Geographical Skills. LOCATE AND DIFFERENTIATE ELEMENTS OF THE EARTH’S SURFACE. Direction. Latitude and longitude. Grid reference. Scale. A model of an A380 at 1:200 scale. Maps are often known as large scale or small scale .
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Scale A model of an A380 at 1:200 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.
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. Aerial, oblique and ground-level photography 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.
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."
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
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."
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 Pie charts
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.
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
Location Quotient 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 The Location Quotient is a measure of the concentration of industry in a region compared to thenational average eg if 15% of manufacturing employment in a region is in textiles and the nationalaverage for textile employment is only 5% then the LQ for textiles in this region will be 15/5 or 3. Thismeans that textile employment in the region is three times more important than nationally. 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.