Measurement and Spatial Data - Part 2 Flashcards
Levels of Measurement (wiki definition)
a classification that describes the nature of information within the values assigned to variables
Levels of Measurement is organized under the principle of….
invariance under transformation (i.e. scale retains its information…)
Steven’s theorized four levels of measurement
Nominal
Ordinal
Interval
Ratio
Nominal
Objects can be classified into groups. Nominal offers names, symbols or labels for categories.
Example:
Liberals, Conservatives.
Categories of Rocks.
Ordinal
Rank ordering of data.
Describes order, but not the relative size or degree of difference between the items measured.
Example: rating systems, ranking data.
Likert scale is a type of ordinal scale!
Interval
Arbitrary zero
Quantitative attributes are all measurable on interval scales, as any difference between levels of an attribute can be multiplied by any real number to exceed or equal another difference
Example: Celsius, Calendars
Ratio
Non arbitrary zero.
Measurement is the estimation of the ratio between a magnitude of a continuous quantity and a unit magnitude of the same kind.
Example: mass, length, time, plane angle, etc.
Other system of levels of measurement
Discrete vs. Continuous
Discrete
Discrete data cannot be dived. It is distinct and separate
Continuous
Continuous data is measure and may take on any value within a finite or infinite interval
Discrete (4 levels of measurement)
Nominal
Ordinal
Continuous (4 levels of measurement)
Interval
Ratio
Types of Scales
Extensive
Derived
Derived Scales (intensive scales)
Have an arbitrary zero.
GEOGRAPHIC INFORMATION INVOLVES THE THREE COMPONENTS OF…
TIME
SPACE
ATTRIBUTE
…. each with its own reference system and system of meaning.
