Chapter 2 Flashcards
Empiricism
Knowledge of the world can be acquired by observing it
Scientific Method
A procedure for using empirical evidence to establish facts
Theory
Explanations of natural phenomena
Hypothesis
A falsifiable prediction made by a theory
-> something you TEST not something you prove
Empirical Method
A set of rules and techniques for observation
Operational Definition
A description of a property in measurable terms
A GOOD operational definition is
- Precise
- Practical
- Quantitative
- Has good interobserver reliability
Construct Validity
A feature of operational definitions whose specified operations are generally considered good indicators of the specified properties
Power
A detectors ability to detect changes in the magnitude of a property
Reliability
A detectors ability to detect the absence of differences or changes in the magnitude of a property
Demand Characteristics
Those aspects of an observational setting that causes people to behave as they think someone else wants or expects
Naturalistic Observation
A technique for gathering information by unobtrusively observing people in their natural environments
Observer Bias
The tendency for observers expectations to influence both what they believe they observed and what they actually observed
Double-Blind Study
A study in which neither the participants nor the researcher knows how the participants are expected to behave
Population
A complete collection of people
Sample
A partial collection of people drawn from a population
Frequency Distribution
A graphic representation showing the number of times that the measurement of a property takes on each of its possible values
Normal Distribution
a mathematically defined distribution in which the frequency of the measurements is highest in the middle and decreases symmetrically in BOTH directions
Mode
The value that occurs most frequently in a set of data
Median
The middle number of a set of data
Mean
The average value of all the measurements in a set of data
Range
The value of the largest measurement in a frequency distribution minus the smallest value of a measurement
Standard Deviation
A statistic that describes how each of the measurements in a frequency distribution differs from the mean
Variable
A property that can have more than one value
Correlation
A relationship between variables in which variations in the value of one variable are synchronized with variations in the value of the other
Correlation Coefficient (r)
A mathematical measure of both the direction and strength of a correlation, which is symbolized by the letter r
Natural Correlation
A correlation that is observed in the natural world
Third-Variable Problem
The fact that the natural correlation between two variables cannot be taken as evidence of a casual relationship between them because a third variable might be causing them both
Experimentation
A technique for establishing the casual relationship between variables
Manipulation
A technique for determining the casual power of a variable by actively changing its value
Independant Variable
The variable that is manipulated during an experiment
Dependant Variable
The variable that is measured in an experiment
Self-Selection
A problem that occurs when anything about a participant determines the value of the independent variable to which the participant was exposed
Random Assignment
A procedure that assigns participants to conditions by chance
Internal Validity
An attribute of an experiment that allows it to establish casual relationships
External Validity
An attribute of an experiment in which variables have been operationally defined in a representative way
The extent to which you can generalize the findings of a study
Case Method
A procedure for gathering scientific information by studying a single individual
Random Sampling
A technique for selecting participants that ensures that every member of a population has an equal chance of being included in the sample
Replication
An experiment that uses the same procedures as a previous experiment but with a new sample from the same population
Type I Error
An error that occurs when researchers conclude that there is a causal relationship between two variables when in reality there is not
Type II Error
An error that occurs when researchers conclude that there is not a casual relationship between two variables when in reality there is
Informed Consent
A verbal agreement to participate in a study made by an adult who has been informed of all the risks that participation may entail
Debriefing
A verbal description of the true nature and purpose of a study
