Quanti - Level of Measurement Flashcards
What is measurement?
“process of assigning numbers or values to individuals’ health status, objects, events, or
situations using a set of rules”
Critical in quantitative research -> statistical analyses
Is the process of assigning a number
Want to evaluate measure and determine if it is trustworthy
What are the advantages of measurement?
- Improves accuracy of results
- removes guesswork in gathering and communicating information
- provides a language for communication and analysis
What are the levels of measurement?
Ratio (Highest)
Interval
Ordinal
Nominal (Lowest)
Describe nominal scale:
- lowest of the four levels of measurement
- uses arbitrary numbers (eg. male = 1, female = 2)
RULES:
- Can’t be rank-ordered (one is not better than the other)
- Must be exclusive and exhaustive categories
What are exclusive and exhaustive categories?
exclusive: categories don’t overlap
exhaustive: everything can be classified, no leftovers
What to analyse for nominal scale?
Mode
- most frequency occurring
- may have multiple modes
Frequencies
- counts
- percentages
What is an ordinal scale?
- the order of numbers matters
- the categories can have UNEQUAL INTERVALS
RULE:
- categories can be RANKED
eg.
1 = <$25,000
2 = $25,000-$54,999
3 = $55,000 -$99,999
4 = >$100,000
e.g. pain level (mild: 1, moderate: 2, severe: 3)
What can be measured on an ordinal scale?
Level of education
Satisfaction rating
e.g. what is the highest degree or level of education you have completed?
high school: 1, bachelor’s degree: 2, master’s degree: 3, PhD or higher: 4
What to analyse for ordinal scale?
Median
- select the number that is exactly in the middle
- place the numbers in value order
Mode
- most frequency occurring
- may have multiple modes
Frequencies
- count
- percentage
What is an interval scale?
RULE:
- lacks a zero point or fixed beginning
- can’t count ratios
- order of numbers maters
- EQUAL NUMERICAL DISTANCES BETWEEN INTERVALS
- numerical value means something on the real number scale (smaller values mean smaller amounts & vice versa)
What can be measured on an interval scale?
- temperature (0deg does not indicate absence of temperature)
- SAT scores (400-1600)
- credit scores (300-850)
- satisfaction (LIKERT scale) - extremely dislike, dislike, neutral, like, extremely like
What to analyse for interval scale?
Median
- Select the number that is exactly in the middle
- place numbers in value order
Mode
- most frequency occurring
- may have multiple modes
Frequencies
- counts
- percentages
Mean
- average of all respondents’ answers
- addition
- subtraction
What is a ratio scale?
HIGHEST form of measurement
Ratio data analysed with greater precision and strength to determine significant relationships and differences
RULE:
- ABSOLUTE ZERO POINT- there is an absence of the attribute being measured
What can be measured on a ratio scale?
Weight (lost physical measures e.g. height, no. of children, etc)
Money
What to analyse for ratio scale?
Median
- Select the number that is exactly in the middle
- place numbers in value order
Mode
- most frequency occurring
- may have multiple modes
Frequencies
- counts
- percentages
Mean
- average of all respondents’ answers
- addition
- subtraction
- MULTIPLICATION
- DIVISION
