Ahmed Alsanousi CSC 464 Types of instruments Existing instruments Oscilloscope Reuse rating scale Create an instrument Survey Checklist Paper and pencil Tangible and intangible Measurement Definition ID: 385682
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Slide1
Measurement & Reliability
Ahmed Alsanousi
CSC 464Slide2
Types of instruments
Existing instruments
Oscilloscope
Re-use rating scale
Create an instrument
Survey
Checklist
Paper and pencil
Tangible and intangibleSlide3
Measurement Definition
Measurement is limiting the data of any phenomenon –substantial or insubstantial– so that those data may be interpreted and, ultimate, compared to a particular qualitative or quan
titative
standard.Slide4
Types of measurement scales
Nominal Scales
Ordinal Scales
Interval Scales
Ratio ScalesSlide5
Nominal Scales
Comes from Latin “
nomen
” means Name
Used to Limits the data
Example: Boys & girls in class
Statistical procedures could be used
Mode: for most frequent occurrence
Percentage: part of total
Chi-square test: compare occurrence between categoriesSlide6
Ordinal Scales
> (greater than) < (less than)
Used to rank-order our data
Example: Classification by education degree
Statistical procedures could be used
Median: determine half-way
Percentile rank: determine position of item in a groupSlide7
Internal Scales
Two features
Has equal units of measurements
Zero point is arbitrarily
Example: Temperature
Statistical procedures could be used
Mean
Standard deviationSlide8
Ratio Scales
Two features
Has equal units of measurements
Zero point is an absolute zero
Example: Ruler
Rarely used outside physical science
Can express values in multiples or fractionsSlide9
Compression
If you can say that
One object is different from another
you have a nominal scale
One object is bigger or better or more of anything than another
You have a ordinal scale
One object is so many units more than another
You have a interval scale
One object is so many times as big or bright or tall or heavy as another
You have a ratio scaleSlide10
Reliability of Measurement instruments
Reliability is the consistency with which a measuring instrument yields a certain, consistent result when the entity being measured hasn’t changes
Example: waistline tape measureSlide11
Forms of reliabilities
Interrater
reliability
Two testers, same result
Test-retest reliability
Retest in different occasions, same result
Equivalent forms reliability
Different versions or instrument, same result
Internal consistency reliability
Different items within instrument, same resultSlide12
Two steps to determine reliability
Getting two measures by using one form of reliability
Calculate how similar are the results