PSYCH 301 FINAL EXAM QUESTIONS & ANSWERS
3 things that affect the statistical Sig. of a correlation (r) - Answers - sample size
confidence interval
strength of correlation
3 things that affect the strength of a correlation - Answers - restriction range
outliers
reliability of measures
partial correlation - Answers - correlation between 2 variables with influence of one or
more other variables statistically removed.
3 characteristics of a well designed experiment - Answers - -vary at least 1
independent variable
-assign subjects to conditions
-control extraneous variables
simple random - Answers - every Ss has an equal chance of being in one of the levels
of the assignment
matched random - Answers - participants are matched prior to the study and then
assigned to a group.
variance - Answers - How much Ss scores differ and vary from one another.
between groups variance - Answers - variance in the score due to experimental
conditions
seeks to maximize treatment variance and eliminate confound variance
error variance - Answers - individual differences
transient or temporal states
environment
factorial design - Answers - 2 or more IVs are manipulates also known as 2 way
factorial design
ex. 2 x 3
there is two IVs the first IV has 2 levels and the second IV has three levels
different IVs measure effect on the same DV
6 commandments of being a good experimenter - Answers -
Quasi experimental design - Answers - when subjets cannot be randomly assigned to
different treatment conditions
the IV cannot be manipulated
, low IV
pre-test post test design - Answers - used when we want to assess whether the
occurrence of an event increases/ decreases the existing level of behavior.
time series design - Answers - measure the DV on several occasions before and after
the quasi independent variable occurs
ex 01 02 03 X 04 05 06
null hypothesis - Answers - we want to reject the null which is the opposite of our
hypothesis being tested
alternate hypothesis - Answers - we want to accept he alternate hypothesis. the means
of group 1 do not equal the means of group 2.
type 1 error (most common type of error) - Answers - researcher concludes that the IV
had an effect on the DV, when in fact the difference between means was due to error
variance
type 2 error - Answers - researcher concludes that the IV did not have an effect on the
DV when in fact it did.
t test result format - Answers - t(df) = ___, p=.05
if significant and
t(df) = ___, p>/<.05 if not significant
Types of IVs - Answers - Environmental manipulation of the Ss physical or social
environment
Instrumental differences in verbal instructions given to Ss
Invasive creating physical changes in the Ss body
Experimental group - Answers - receives the zero level of the IV
you need at least two groups
control group - Answers - receives a zero level of the IV
it is not always necessary
repeated measures design - Answers - because both groups will switch off between
experimental and control group no random assignment is needed.
confound variance (want to minimize) - Answers - Produced when variable other than
the IV differs between the groups
it is a threat to internal validity
Internal validity - Answers - when high it means that the X variable had an effect on the
Y variable. the independent variable imoact the dependent variable
3 things that affect the statistical Sig. of a correlation (r) - Answers - sample size
confidence interval
strength of correlation
3 things that affect the strength of a correlation - Answers - restriction range
outliers
reliability of measures
partial correlation - Answers - correlation between 2 variables with influence of one or
more other variables statistically removed.
3 characteristics of a well designed experiment - Answers - -vary at least 1
independent variable
-assign subjects to conditions
-control extraneous variables
simple random - Answers - every Ss has an equal chance of being in one of the levels
of the assignment
matched random - Answers - participants are matched prior to the study and then
assigned to a group.
variance - Answers - How much Ss scores differ and vary from one another.
between groups variance - Answers - variance in the score due to experimental
conditions
seeks to maximize treatment variance and eliminate confound variance
error variance - Answers - individual differences
transient or temporal states
environment
factorial design - Answers - 2 or more IVs are manipulates also known as 2 way
factorial design
ex. 2 x 3
there is two IVs the first IV has 2 levels and the second IV has three levels
different IVs measure effect on the same DV
6 commandments of being a good experimenter - Answers -
Quasi experimental design - Answers - when subjets cannot be randomly assigned to
different treatment conditions
the IV cannot be manipulated
, low IV
pre-test post test design - Answers - used when we want to assess whether the
occurrence of an event increases/ decreases the existing level of behavior.
time series design - Answers - measure the DV on several occasions before and after
the quasi independent variable occurs
ex 01 02 03 X 04 05 06
null hypothesis - Answers - we want to reject the null which is the opposite of our
hypothesis being tested
alternate hypothesis - Answers - we want to accept he alternate hypothesis. the means
of group 1 do not equal the means of group 2.
type 1 error (most common type of error) - Answers - researcher concludes that the IV
had an effect on the DV, when in fact the difference between means was due to error
variance
type 2 error - Answers - researcher concludes that the IV did not have an effect on the
DV when in fact it did.
t test result format - Answers - t(df) = ___, p=.05
if significant and
t(df) = ___, p>/<.05 if not significant
Types of IVs - Answers - Environmental manipulation of the Ss physical or social
environment
Instrumental differences in verbal instructions given to Ss
Invasive creating physical changes in the Ss body
Experimental group - Answers - receives the zero level of the IV
you need at least two groups
control group - Answers - receives a zero level of the IV
it is not always necessary
repeated measures design - Answers - because both groups will switch off between
experimental and control group no random assignment is needed.
confound variance (want to minimize) - Answers - Produced when variable other than
the IV differs between the groups
it is a threat to internal validity
Internal validity - Answers - when high it means that the X variable had an effect on the
Y variable. the independent variable imoact the dependent variable
