Experimental Psychology Flashcards
the dimension that the experimenter intentionally manipulates. (2) sometimes aspects of the physical environment that can be brought under the experimenter’s direct control.
Independent variable
particular behavior we expect to change because of our experimental treatment. (2) the outcome we are trying to explain.
Dependent variable
specifies the precise meaning of a variable within an experiment. (2) defines a variable in terms of observable operations, procedures, and measurements. (3) it clearly describes the operations involved in manipulating or measuring the variables in an experiment.
Operational Conditioning
explain the precise meaning of the independent variables. (2) includes all the steps that were followed to set up each value of the IV.
Experimental Operational definitions
condition was defined by the electronic equipment set up in the room
The high-anxiety
was defined by the absence of equipment.
low-anxiety condition
describe what we do to measure the variables. (2) describe exactly what procedures we follow to assess the impact of different treatment conditions.
Measured Operational Condition
internal attributes or characteristics that cannot be directly observed
Construct
identifies the set of operations required to measure an external behavior. Uses the resulting as both definition and measurement of a hypothetical construct
Operational condition
It is easy to see why operational definitions are required when we are dealing with constructs. Something that cannot be seen must be defined by observable dimensions before we can deal with it scientifically. However, operational definition is equally important when we are working with variables that can be observe more directly.
Nonconstruct Variables
In setting up experiments and formulating operational definitions, researchers also consider the available scales of measurement for each variable. Many variables can be measured in more than one way. The measurement alternatives differ in the degree of information they provide.
Scales Of Mesurements
The simplest level; classifies items into two or more distinct categories that can be named
Nominal
The next level; the magnitude of each value is measured in the form of ranks
Ordinal
Higher level; measures magnitude or quantitative size using measures with equal intervals between the values. Scales
Interval
highest level. measures magnitude or quantitative size using measures with equal intervals. between all values and a true zero point
Ratio
refers to the consistency of experimental operational definitions and measured operational definitions. (2) means consistency and dependability. Good operational definitions are reliable.
RELIABILITY
degree to which observers agree in their measurement of the behavior. this method is used in a content analysis, when raters must score the qualitative content of subjects’ responses.
Interrater Reliability
the degree to which a person’s scores are consistent across two or more administrations of a measurement procedure.
Test-Retest reliability
measures the degree to which different parts of an instrument (questionnaire or test) that are designed to measure the same variable achieve consistent results.
Interitem Reliability
splitting the test into two halves at random and computing a coefficient of reliability between the scores obtained on the two halves.
Split half reliability
most widely used method for evaluating interitem reliability because it considers the correlation of each test item with every other item; it is like measuring split-half reliability for all possible ways a test could be split up into halves.
Cronbach’s α (Alpha)