PSYCH STAT
STATISTICAL TECHNIQUES MAIN FUNCTIONS:
1.) They provide ways of summarizing the
information that we collect from a
multitude of sources.
2.) Branches of Statistics
Inferential Statistics –
- About the economy of effort in
research
- About the confidence with which
we can generalize from a sample to
the entire population.
Ex: The mean SAT score of an 11th
graders in the US.
Descriptive Statistics –
- Describe, show, and summarize the
basic features of a dataset found in
a given study, presented in a
summary that describes the data
sample and its measurements.
Ex. Popularity of different leisure
activities by gender.
3.) The amount of data that researcher can
collect is potentially massive.
Variable
- vitally important in statistics
- is anything that varies and can be
measured
Ex: Gender, Eye color
Scores – numerical values
MAJOR TYPES OF MEASUREMENT
1.) Score/Numerical Measurement
- The assignment of a numerical
value to a measurement.
- Includes most physical and
psychological measures.
2. Nominal/Category Measurement
- deciding to which category of a variable a
particular case belongs.
- appropriate to refer to it as “Qualitative
Measure”
Ex. Occupation, Gender
Lorry Driver – is a name or verbal description of
what sort of case should be placed in that
category.
FORMAL MEASUREMENT THEORY
1.) Nominal Categorization
- Placing of cases into named
categories
- Nominal clearly refers to “name”
- - exactly the same as nominal
measurement or categorization
process
2.) Ordinal (or rank) measurement
- Values of the numerical scores tell
us other than which is the smallest
to which is the largest.
- Sometimes called as “rank
measurement”
3.) Interval or equal-interval measurement
- The intervals between numbers on
a numerical scale are equal on size.
4.) Ratio Measurement
- Has an absolute zero point that is
measured as 0
- Zero is the smallest distance one
can have.
THE DIFFERENCE SCALES OF MEASUREMENT
NOMINAL CATEGORIES
a.) Involves putting a variable into a small
number of categories
b.) The categories do not correspond to
numerical values
