Dependent Sample T-tests

Question 1

Related Sample

Answer 1

Participant scores are dependent or related to each other, whether by repeated-measures design or by matched pairs design.

Question 2

Repeated-measures design

Answer 2

The same participants are tested and then tested again, whether pre-post or within-subjects

Question 3

pre-post design

Answer 3

A single group are tested for a factor, a treatment is applied, and then they are tested for that factor again after the treatment.

Question 4

Matched-pairs design

Answer 4

design where participants are matched in pairs that are related to each other, whether after an experimental trait has been measured or through naturally occurring factors

Question 5

Related Samples t test

Answer 5

A statistical method for comparing differences between related samples being measured

Question 6

difference score

Answer 6

A method of eliminating error arising from observing different participants

Question 7

error (standard error of the mean)

Answer 7

a difference between scores that can’t be caused by/attributed to the different treatments; difference that occurs by chance.

Question 8

Related Samples advantages

Answer 8

1. Practicality, like in learning/developmental experiments
2. Less overall standard error: computing the difference scores reduces between persons error
3. Increase of power: based on #2, the less standard error, the more power, and the more likely you are to reject the null and find a statistically significant difference

Question 9

Related-Sample T-Test formula

Answer 9

Tobt=Md-µd/Smd

Question 10

Estimated standard error for difference scores (Smd)

Answer 10

Smd=sqrt s^2D/nD, or sD/sqrt nD

Question 11

DF for related samples t-test

Answer 11

nD-1

Question 12

Related-Samples t-test assumptions

Answer 12

1. Normal distribution
2. independence within groups: difference scores were obtained from different individuals from within each group/treatment

Question 13

mD formula

Answer 13

mD=ΣD/nD

Question 14

s^2D formula

Answer 14

S^2D=SS/nD-1

Question 15

Sum of Squares for difference

Answer 15

ΣD^2-(ΣD)^2/nD

Question 16

Estimated cohen’s d for the difference

Answer 16

d=mD/sD

Question 17

Proportion of variance for the difference

Answer 17

η^2=t^2/t^2+df

Question 18

omega-squared

Answer 18

ω^2=t^2-1/t^2+df

Question 19

Confidence intervals (estimation)

Answer 19

Setting limits for population parameter within which it is 95% likely to be contained

Question 20

Point estimate

Answer 20

A specific point (sample mean)

Question 21

interval estimate

Answer 21

A set of top and bottom scores within which the population parameter is likely to sit

Question 22

interval estimate

Answer 22

A set of top and bottom scores within which the population parameter is likely to sit

Question 23

Estimation formula

Answer 23

mD+/-t(sMD)