Psych 301.txt

A research technique in which the researcher simply observes and describes behavior

Correlational studies are used to look for relationships between variables

A variable under the control of the experimenter that may effect the dependent variable in a reliable fashion.

The variable being examined by the researcher. It may or may not be effected by the IV

An experimental design in which each subjects is randomly assigned to only one of the treatment conditions

An experimental design where all subjects receive all treatment conditions. Also called a repeated measures design

An error of statistical inference when the null hypothesis is rejected when it is true. This is an error of "seeing too much in the data."

An error of statistical inference when the null hypothesis is retained when it is false. This is an error of "not seeing enough in the data."

Variables not under the control of the experimenter that vary systematically with the independent variable

Experimental designs in which two or more independent variables are used. This permits the analysis of interactions between variables.

any variable other than the IV that affects the DV

• Floor - The values of the DV are so low they are not affected by the IV
• Ceiling - The values of the DV are so high they are not affected by the IV

The effect of the change in level of one factor in a factorial experiment measured independently of other variables.

The tendency of an interviewee to agree with the questioner.

• Random - An IV whose levels were chosen randomly from a population of possible values
• Fixed - An IV whose levels were chosen non-randomly

• If P then Q
• P
• Therefore Q

• If P then Q
• Not Q
• Therefore not P

Using Modeus Ponens backwards (If P then Q, Q, There for P) this form of logic is invalid, based upon this example

• If Bill Gates owns Fort Knox, then he is rich
• Bill Gates is rich.
• Therefore, Bill Gates owns Fort Knox.

• Identity Property
• Occurs when different entities receive different scales

• Magnitude Property
• Occurs when the ordering of values on the scale reflects the ordering of the trait being measured

• Equal intervals
• Occurs when a difference of 1 on the scale represents the same amount of the trait being measured everywhere on the scale (e.g. weight in pounds)

• Absolute Zero
• Occurs when a score of 0 indicates a complete absence of the trait being measured

• Nominal - Identity Property
• Ordinal - Identity, Magnitude
• Invertal - Identity, magnitude, Equal Intervals
• Ratio - Identity, Magnitude, Equal intervals, absolute zero

A design where random assignment or selection cannot be used due to impractibility or impossibility

• Alpha level
• Sample size
• Effect size
• One tailed vs Two tailed
• Variance

• Require less work/paperwork
• Multiple t-tests inflate the type 1 error rate

• We don't know the direction of the cause - Does X cause Y or does Y cause X?
• A third variable "Z" may be involved that is responsible for the covariance between X and Y

• 1. Less restrictive assumptions
• 2. Often easier to calculate than parametric tests

• 1. Tend to be overly conservative
• 2. No non-parametric tests exist for some research
• designs (e.g. factorial designs)

• Carry-over effects
• Ethical problems
• Order effects
• Irreversibility

• Subjects should agree to participate in research
• Subjects should not be coerced
• Subjects should be fully informed about the purpose of the experiment before deciding to participate
• Subject data should be confidential
• Subjects should be warned of any harmful effects of the study

results from the previous phase carry-over into the next phase

Sensitization effects occur when the subject is aware of the manipulations used in a study and such awareness causes him/her to change his/her behavior

• Internal - How well it measures what its supposed to
• External - How well the results can be generalized

To prevent practice effects and counter balance

• Aspects of a study that indicate to subjects how they are
• expected to respond

Occurs when the DV is affected by the IV, not because of any inherent qualities of the IV but rather because the IV is something new