Chapter 8

Question 1

Defined as the process of assigning numerals to variables to represent quantities of characteristics according to certain rules

Answer 1

Measurement

Question 2

What are the uses of measurement

Answer 2

Describing quantity to determine value
Making decisions
Drawing comparisons
documenting change or progress
Discriminating
Predicting outcomes

Question 3

Dichotomous variables can only take on how many variables

Answer 3

2

Question 4

Ex of dichotomous variables

Answer 4

Yes or no on a survey

Question 5

Polytomous variables can have how many values?

Answer 5

Many

Question 6

Ex of polytomous variables

Answer 6

5 point opinion scale

Question 7

can have any value along a continuum within a defined range

Answer 7

Continuous variables

Question 8

Ex of continuous variable

Answer 8

Wt in lbs

Question 9

Discrete variables can only be described in

Answer 9

Whole integer units

Question 10

Ex of discrete variables

Answer 10

Heart rate in beats per minute

Question 11

Ex of direct observations of a physical property

Answer 11

range of motion in degrees or length in centimeters

Question 12

For measures that are not observable, use an indirect or proxy measure. An example of this is

Answer 12

the height of a column of mercury to measure temperature

Question 13

Measured as some value assumed to represent the underlying variable

Answer 13

Abstract variables

Question 14

Ex of abstract variables

Answer 14

Intelligence, health, strength

Question 15

Levels of measurement

Answer 15

●Nominal
●Ordinal
●Interval
●Ratio

Question 16

Classifications
●No relative order
●Numbers, letters or words may be used as category labels
•Blood type
•Gender
•Diagnosis
●Arithmetic properties: counting (frequency)

Answer 16

Nominal scale

Question 17

Numbers indicate rank order
●Intervals inconsistent or not known
●Examples: manual muscle test, function, pain
●Arithmetic properties: counts, percentages
•Medians useful for central tendency
•Cannot be added, subtracted, multiplied, or divided

Answer 17

Ordinal scale

Question 18

Numbers indicate rank order and demonstrate equal intervals
●No true zero
●Examples: temperature in Fahrenheit or Celsius
●Arithmetic properties: addition and subtraction

Answer 18

Interval scale

Question 19

Numbers indicate equal intervals and have a true zero
●Examples: age, height, weight
●Arithmetic properties: addition, subtraction, multiplication, and division

Answer 19

Ratio scale

Question 20

What is the relevance of measurement scales?

Answer 20

Determination of which mathematical operations are appropriate
●Determination of which interpretations are meaningful
●Statistical procedures
•Parametric versus nonparametric tests