Maps, graphs, statistics, data interpretation and geographical arguments.
Notes and quizzes readyCore topic
Revise the key ideas
Reading maps and locations
Latitude measures angular distance north or south of the Equator; longitude measures east or west of the Greenwich meridian. Read the direction letters as well as the numbers.
Describe distributions using location, concentration, gaps and exceptions. Use place names and map evidence rather than saying features are spread everywhere.
The scale 1:25 000 means one map unit represents 25 000 of the same units on the ground: one centimetre represents 250 metres. At 1:50 000, one centimetre represents 500 metres.
A larger-scale map, such as 1:25 000, shows a smaller area in more detail than 1:50 000. A scale bar remains useful when an image is resized; a printed ratio may no longer match physical ruler measurements.
Measure straight-line distances with a ruler and the correct scale. For a curved route, use thread or short measured segments, then convert to ground distance.
Area uses squared units: one square kilometre is one million square metres. A map square one kilometre on each side covers one square kilometre.
Grid references, direction and relief
Eastings increase to the east and northings to the north. Read along the corridor, then up the stairs: easting first, northing second.
A four-figure grid reference identifies a square using the easting and northing of its south-west corner. It does not pinpoint the feature within the square.
A six-figure reference divides each grid square into tenths. Give the three-digit easting then the three-digit northing without swapping their order.
For an illustrative feature four tenths across square 23 and seven tenths up square 45, the six-figure reference is 234457. This is a worked grid example, not the location of a named landmark.A six-figure grid reference. Read eastings before northings. This is an invented teaching grid, not an OS map of a real location.
Compass directions include north, north-east, east and the other main points. Bearings are measured clockwise from north: east is 090°, south 180° and west 270°.
Contours join points of equal elevation above the map's datum. Check their labels and contour interval; close contours usually indicate steeper slopes.
Spot heights mark elevation at a particular point. A triangulation pillar is a surveyed feature and is not interchangeable with every spot-height symbol.
Gradient is vertical change divided by horizontal distance in matching units. A 50 m rise over 1 000 m is 1:20; use horizontal distance, not the sloping path length.Calculate gradient using matching units. The horizontal and vertical dimensions are schematic, not drawn to the same scale. Do not use the length along the slope as horizontal distance.
To draw a relief cross-section, mark contour crossings along a line and plot their heights against distance using a labelled vertical scale. Join them with a plausible smooth land profile.
A transect records features along a line, such as land use from a town centre outward. It can show relationships but may not represent places away from that route.
Use map symbols and the key to identify roads, buildings, woodland, paths and water. Infer tourism from a combination of evidence rather than one unexplained symbol.
Compare coastal maps for headlands, bays, beaches and spits; river maps for meanders, floodplains and valley sides; glacial maps for steep corries, U-shaped valleys and lakes. Explain how contour and drainage evidence support identification.
Photographs, sketches and GIS
Ground photographs show a view from near the surface; oblique aerial images show a sloping view; vertical aerial or satellite images give an overhead view. Perspective affects apparent distances and sizes.
Match photographs to maps using several landmarks, such as river bends, roads and hills. Check view direction and whether dates differ.
A geographical sketch selects important features rather than copying every detail. Label observations and annotate explanations supported by evidence.
GIS combines geographically located data in layers, such as population, flood zones and roads. Comparing layers can reveal patterns, but data accuracy and scale still limit conclusions.
Choosing graphs
Bar charts compare categories and normally have spaces between bars. A line graph shows change across an ordered continuous variable, such as time or distance.
Histograms display grouped numerical data with adjoining bars. For equal class intervals, frequency can be plotted consistently; do not treat unrelated categories as continuous classes.
A pie chart shows parts of a whole. Calculate each sector as category value ÷ total × 360°; 25% makes a 90° sector.
A divided bar also shows proportions of a total. Equal-length bars help compare percentages when group totals differ, but the absolute totals should still be stated.
A pictogram uses repeated symbols for quantities. Include a key and interpret partial symbols correctly rather than enlarging symbols inconsistently.
A scattergraph plots paired numerical values to investigate a relationship. Label both axes and plot each pair accurately.
Positive correlation means values tend to increase together; negative correlation means one tends to decrease as the other increases. No clear correlation does not mean no conceivable connection.
A line of best fit follows the overall pattern, rather than joining every point or forcing the line through the origin. Correlation does not by itself establish causation.Positive correlation and a best-fit line. Axes are schematic: these points illustrate a relationship and are not fieldwork results. A best-fit line follows the overall pattern rather than joining points.
Interpolation estimates within the observed range. Extrapolation estimates beyond it and is less secure because the relationship may change.
Population pyramids show age groups and sex categories, with population numbers or percentages on the horizontal axes. Read the units; a wide base suggests a large young share, not a precise future birth rate.
Dispersion graphs show individual observations along a scale, making spread and clusters visible. Several groups with similar averages can still have very different spreads.
Thematic maps
Choropleth maps shade areas according to value classes. Rates or percentages are often more comparable than raw totals when areas have different populations.
Choropleth boundaries can hide variation inside each area. Class thresholds and colour choices can change the apparent pattern, so read the key carefully.
Isolines join equal values, such as temperature or rainfall. Close lines indicate rapid change across distance; contour lines are a height-based example.
Dot maps represent quantities using dots of a stated value. A dot within a district may represent an allocation, not the exact location of each individual.
Proportional symbols vary in size with quantity. If circle area is proportional to value, doubling the value does not double its radius.
Desire lines join origins and destinations to show connections. Flow lines can use width and arrows to indicate quantity and direction; they may not trace the actual route.
Calculations and statistics
A ratio compares quantities, while a proportion is a part of a whole. Keep units consistent and state whether a figure is an absolute number, rate or percentage.
Mean is total divided by number of observations. For illustrative readings 2, 3, 3, 6 and 11, the mean is 25 ÷ 5 = 5.
Median is the middle value after ordering; with an even number, average the middle two. The illustrative set 2, 3, 3, 6, 11 has median 3.
Mode is the most frequent value: the illustrative set's mode is 3. A modal class is the grouped interval with the highest frequency; it does not identify an exact individual value.
Range is maximum minus minimum. For the illustrative set it is 11 − 2 = 9; the mean and range are both affected by extreme values.
Quartiles divide ordered data into four parts. The inter-quartile range is upper quartile minus lower quartile and describes the middle half of the observations.
Cumulative frequency is the running total at or below each class boundary. Use it to estimate the median at half the total frequency and quartiles at one-quarter and three-quarters.
A percentile gives the value at or below which a stated percentage of observations falls. The 90th percentile is not the same as 90% of the maximum reading.
Percentage change is (new − original) ÷ original × 100. A rise from 40 to 50 is 25%; this is an illustrative calculation, not a case-study statistic.
A rise from 40% to 50% is ten percentage points and a 25% relative increase. State which comparison you are making.
Population density is population divided by area. For an illustrative 12 000 people over 30 km², density is 400 people per km².
Use units and show working. Check whether an answer is reasonable and round only at the end when intermediate rounding would alter the result.
Judging and communicating evidence
Look for misleading axes, selective dates, inconsistent boundaries and averages that hide inequality. Compare absolute totals with rates before deciding one place performs better.
Assess sample size, selection, measurement quality and data age. A precise-looking number can still be unreliable or unrepresentative.
Quantitative evidence measures amounts; qualitative evidence explains characteristics or experiences. Using both can provide a fuller explanation when their limitations are considered.
Describe states what the evidence shows; explain gives reasons; assess or evaluate weighs evidence to reach a judgement. Read the command word and focus on the specified place or issue.
Extended answers need a connected argument, relevant evidence and a justified conclusion. Clear sentences and accurate geographical terms help communicate the reasoning.
Test yourself
50 questions · Random sets of 10. These quick checks support revision; practise longer explanations and justified judgements too.
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