Thematic Mapping Techniques Questions and Answers

Answer: A

Correct answer: concentrates on the distribution of one subject

A general reference map shows whatever is there - roads, rivers, settlements, relief - without arguing for any of it. A thematic map takes one subject and makes its distribution the point of the sheet, with everything else demoted to a base that locates the theme. Scale, publisher and coordinate framework have nothing to do with the distinction; a thematic map may be at any scale and produced by anyone.

Answer: B

The base supplies enough geography for the reader to locate the pattern without competing with it. It is usually drawn in a lighter weight for exactly that reason, which is a figure-ground decision as much as a content one.

Answer: C

Knowledge of where people cannot live, such as lakes or industrial land, lets the mapper redistribute a unit's value onto the ground that actually carries it. The result respects real limits rather than the arbitrary administrative outline.

Answer: D

Isometric lines join points where the value was actually measured, such as temperature at a weather station. Isopleths are built from area-based ratios assigned to a notional centre, which makes them a step further removed from observation.

Answer: A

It is a conceptual surface in which height stands for the value of some variable, such as population density or rainfall. Only in the special case of elevation does the surface correspond to something a surveyor could level across directly.

Answer: B

Correct answer: Both A and R are true, and R is the correct explanation of A

Both are true and the reason is the cause. A census yields one figure per tract, so the data are a set of values attached to areas, not samples of a field that exists at every point. Interpolating them into a smooth surface invents gradients within units where none was measured and smooths across boundaries where the real change may be abrupt - a visual claim the data cannot support.

Answer: C

Redrawing districts or aggregating them differently can move a correlation or reverse a pattern without any change in the underlying observations. It has two components, one from the scale of aggregation and one from how the boundaries are zoned.

Answer: D

A district with a high average income contains poor households, so concluding that a particular resident is wealthy does not follow. Thematic maps invite the fallacy precisely because they present the area value as a single uniform tone.

Answer: A

Correct answer: 1 and 2 only

Statements 1 and 2 are correct: the modifiable areal unit problem has a scale component, from the size of the units, and a zoning component, from where their boundaries are drawn; and the ecological fallacy is the error of inferring something about individuals from an area aggregate. Statement 3 is wrong - both problems arise from the units themselves, before any classification is applied, so no legend design can remove them.

Answer: B

A count divided by a sensible denominator becomes comparable between units of different sizes. The choice of denominator is itself an argument, since crimes per resident and crimes per square kilometre answer different questions.