Categorical & Cont variables

Mind Map by shirley.ha, updated more than 1 year ago
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Description

HBS108 (Week 6 & 7) Mind Map on Categorical & Cont variables, created by shirley.ha on 09/02/2013.

Resource summary

Categorical & Cont variables
1 Nominal
1.1 simplest and lowest level of measurement
1.2 involves classifying observations into mutually exclusive categories
1.3 Binary scales
1.3.1 allocation of that individual to one of only two possible categories
1.3.1.1 Male/Female
1.3.1.2 smoker/non
1.4 thus participants are assigned to a named category such as 'male' or 'female'
1.4.1 No particular order
1.4.1.1 i.e Budhist, Monks....
1.5 NAMES ONLY
2 Ordinal
2.1 ORDERED
2.1.1 involves ranking of phenomena
2.1.1.1 permits the numeric ranking of objects on the basis of their standing relative to each other on a specified characteristic.
2.1.1.1.1 organised along 'greater than and less than' dimensions
2.1.1.1.1.1 only shows relative magnitude, not quantity
2.1.1.1.1.2 discrete and conceptualised as having inherent order
2.1.1.2 Mutually exclusive
2.1.1.2.1 1 = is completely dependant 2 = is needing another person's assistance 3 = is needing mechanical assistance 4 = is completely independent.
2.1.1.2.2 Only ranks doesn't tell whihc one is better
3 Ratio
3.1 represent the highest level of measurement
3.1.1 Absolute zero point
3.1.1.1 describe ratio properties between values as there is a true zero;
3.2 have all of the characteristics of nominal, ordinal and interval measures
4 Interval
4.1 characteristics of both nominal and ordinal data but also has the characteristics of equal spacing between categories
4.2 indicates how much the categories differ;
4.2.1 demonstrates equal amounts of change in a variable between equivalent distances or intervals between points on a scale
4.2.1.1 does not measure absolute magnitude since the zero on interval scales is arbitrary
4.2.1.1.1 the arbitrary zero does not mean there is 'nothing' of the variable being measured; for example, an IQ of zero does not mean zero intelligence – it just means someone scored zero on an IQ test – maybe because they couldn't read
4.3 No true 0 makes it diff to compare ratios
4.4 specify both the rank order of a characteristics and the distance between those objects.
4.4.1 someone whose IQ increased from 100 to 110 has had the same IQ increase as someone
4.4.1.1 whose IQ has gone from 110 to 120 (i.e. a 10-point increase in both cases).

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