Final Flashcards
Steps of procedure to determine if sample mean differs significantly from population mean.
S^2 =
SS/df
SM =
t =
T test > T critical
reject H0
M
sample mean
μ
population mean
SM
estimated standard error
A larger n would lead to a
larger df and a smaller tC
A larger n would lead to
smaller s2 and a smaller sM, producing a larger tT
A larger n would make rejecting H0
more likely
A smaller SS would lead to a
smaller s2 and a smaller sM
A smaller SS would lead to a smaller s2 and a smaller sM,
producing a larger tT
A smaller SS would lead to a smaller s2 and a smaller sM, producing a larger tT. This would also make rejecting H0
more likely
A larger difference between M and µ - the effect size – would also
increase tT
A larger difference between M and µ - the effect size – would also increase tT, making rejection
of H0 more likely
The increase in alpha level, will reduce
tc
An appropriate procedure to determine if population means (represented here by sample means) are statistically significant from one another.
SS =
tT
Sp
How to Construct a 95% confidence interval
An appropriate procedure to determine if an experiment has had an effect
t statistic
SMD
COHEN’S D formula
D - 0,2
small effect size
D - 0,5
medium effect size
D - 0,8
large effect size
Suppose you have the following data from an experiment involving three-levels of a treatment. Use an appropriate procedure to determine if all population means (represented here by sample means) are not significantly different from one another.
G=
b) Calculate and interpret “variance explained”, also known as η2 for this exercise.
M=
M1 -M2
SOME GENERAL USES OF PEARSON’S CORRELATION
a. PREDICTION: CORRELATION OF EXAM GRADES AND SUCCESS IN COLLEGE
b. ESTABLISHING VALIDITY: A VALID MEASURE MUST CORRELATE TO OTHER MEASURES
c. ESTABLISH RELIABILITY: A RELIABLE MEASURE CORRELATES OVER SEVERAL TIMES
d. THEORY VERIFICATION
IF THE CORRELATION COEFFICIENT IS 0.5,
THEN COEFFICIENT OF DETERMINATION IS 0.52 = 0.25
PEARSON’S CORRELATION IS USUALLY USED WITH INTERVAL OR RATIO-LEVEL MEASUREMENTS AND IT PERTAINS TO A
LINEAR RELATIONSHIP
The equation for predicted values of Y
Interpret the meaning of its coefficients (α and β). Why is there no error tem in the equation?
M=
M1-M2
If the value of zero falls between Lower and Upper C.I., than It is likely, that hypothesis of H is likely to be
failed to reject
If the value of zero does not fall between Lower and Upper C.I.
How to determine if sample mean differs significantly from the population mean.
Determine if population means (represented here by sample means) are statistically significant from one another.
Construct a 95% confidence interval
An appropriate procedure to determine if treatment has had an effect.
Calculate Cohen’s D
Use an appropriate procedure to determine if all population means (represented here by sample means) are not significantly different from one another.
Calculate and interpret “variance explained”, also known as η2 for this exercise
Calculate an appropriate measure of association between variables
Write down a (regression) equation for predicted values of Y and interpret the meaning of its coefficients (α and β). Why is there no error tem in the equation?
Predicted value of Y equals alpha, when
X=0
For one unit change in X and Ŷ changes by
Beta units
We need no error term, because this equation represents the relationship
Between X and the predicted values of Y
