Chapter 3: Statistics Refresher Flashcards
The person who breathes life and meaning into test scores by applying the knowledge and skills to interpret them appropriately.
Test user
They are frequently expressed as numbers, and statistical tools are used to describe, make inferences from, and draw conclusions about numbers.
Test scores
It is the act of assigning numbers or symbols to characteristics of things according to rules.
Measurement
A set of numbers or symbols whose properties model empirical properties of the objects to which the numbers are assigned.
Scale
It refers to the values that variable can take on.
Sample space of a variable
{sample space}
What are the two categorization of scales?
- Discrete scale
- Continuous scale
It has a sample size that can be counted.
Discrete Scale
It involves categorical and quantitative variable. The numbers between the sample space members are not allowed— e.g. 2.5 in {2,3}.
Discrete Scale
Its values can be any real number in the scale’s sample space.
Continuous scales
It includes fractions or numbers with as many decimals as needed; it could have irrational numbers in theory and in practice, measurements have to be rounded.
Continuous Scales
Measurements in this scale always involve error, thus, the answer should be thought as an approximation of the real score.
Continuous Scale
It refers to the collective influence of all of the factors on a test score or measurement beyond those specifically measured by the test or measurement.
Error
These scales involve classification or categorization based on one or more distinguishing characteristics, where all things measured must be placed into mutually exclusive categories.
Nominal Scales
Scales: distinct categories, =
Nominal Scales
It is the simplest form of measurement which includes categories with no defined order.
Nominal Scale
Numbers that serve as unique identifiers.
Numeric Nominal Variable
It implies nothing about how much greater one ranking is than another, and it includes measurements in which people or things are ranked.
Ordinal Scales
Scales: ordered categories, <>
Ordinal Scale
It permits classification with rank ordering on some characteristics, and it has no absolute zero point.
Ordinal Scales
It presumes every testtaker to have some ability.
No absolute zero point
It assigns people to categories with clear and uncontroversial order. It is the most used in psychology.
Ordinal Scales
He believed that the data derived from an intelligence test are ordinal in nature. He also emphasized that what he tried to do with his test was not to measure people, but merely to classify (and rank) people on the basis of their performance on the tasks.
Alfred Binet
Scales: meaningful distances, + -
Interval Scales
It contains intervals between numbers and it contain no absolute zero point.
Interval Scales
It indicates the absence of a quantity.
Absolute Zero
Scales: absolute zero, x /
Ratio Scales
It has a true zero point.
Ratio Scales
All mathematical operations can be performed due to the equal intervals and the absolute zero, and it represents the magnitude of the quantity being measured.
Ratio Scales
A set of test scores arrayed for recording or study.
Distribution
A straightforward, unmodified accounting of performance that is usually numerical. It may reflect a simple tally and it can be converted into other types of scores.
Raw score
