Flashcards in Quiz 1 that i created Deck (56)
What is a variable?
A property that can take different values
Operational definition is
converting construct into a measurable variable
A construct variable is
an abstract (non-observable)
Continuous variable is
any value along a continuum within a defined range
A discrete variable is
described in whole units. Cannot be halved
What are the levels of measurement?
Ratio, interval, ordinal, and nominal
numbers that represents units with equal intervals. Measured from a true zero, and has no negatives. Highest and carries the most info. Ex: distance, age, time
numbers have equal intervals but no true zero. Ex: calendar years, temp
numbers indicate a rank order
numbers are category label. Dichotomous. yes or no answers
What is an independent variable?
What you can manipulate/specify.
What are dependent variables?
What you measure
Types of independent variable
Active and Atrribute
cannot be manipulated. EX: gender
can be manipulated. Ex: treatment given to a group
same group/people are measured in all levels of an IV. They are their own controls. (within subject)
different groups for each level. of IV. (between subjects)
Single factor design
Just one independent variable
two or more IV
only 1 dependent variable
multiple dependent variables
what is reliability
the extent to which a measurement is consistent & free from error
what is measurement error
having the idea that a measurement has a margin of error.
Observed score = true score +/- error
Types of measurement error are
Systematic, and random
What is systematic error
error that is constant in its ways. Either always overestimating or underestimating
What is random error
error that is due to chance from measurement. The measurement are unpredictable
Sources of measurement error
Rater, instrument, or variability of characteristic being observed
Ways to improve reliability
standardize measurement methods, train & test observers, refine & calibrate instruments, blind rater to reduce bias.
what are the two reliability coefficients and what are they used for?
ICC: for continuous scale score
Cohen's kappa: categorical scale scores