2tailedhypothtestst

Question 1

3 conditions necessary to use a t-test for independent. samples:

Answer 1

1) The samples must be independent
2) Each population should have a normal distribution (ignore this assumption when n ≥ 30)
3) Homogeneity of variance
• Both groups must be sampled from populations with similar variance
• If not, can’t pool variances, so df is smaller (which results in larger critical t)

Question 2

Steps for Two-Sample t-Test for the Difference Between Means:

Answer 2

1) State H0 and Ha.
2) Identify a.
3) Is larger variance > 3x the smaller one?
4) df = n1+ n2 – 2 or df = smaller of n1 – 1 or n2 – 1
5) Use t-table
6) determine rejection regions
7) t = (x1 - x2) - (y1-y2)/ SDx1-x2
8) if T is in rejection area, reject H0, otherwise fail 2 reject H0

Question 3

___ measures are considered the “ultimate” in matching bc the same person takes the experiment twice

Answer 3

Repeated

Question 4

Repeated measures can be prone to

Answer 4

Carryover/testing effects

Question 5

Matched pairs but based on biological or social measures

Answer 5

Natural pairs

Question 6

When we compare either the same participants or participants who have some predetermined relationship

Answer 6

Dependent (paired) samples designs

Question 7

To calculate the average difference (numerator d)

Answer 7

d=x1-x2

Ie. measurement 1 - 2

THEN take the average mean of the differences (Sum of d/n=d bar)

Question 9

Using a paired t-test the right value (- miu) is always

Answer 9

0

Question 10

What does n stand for in paired t-tests?

Answer 10

of PAIRS

Question 11

For___ samples t-tests, think of groups of scores rather than than people

Answer 11

dependent

Question 12

2 assumptions of paired t-test

Answer 12

1) samples must be dependent (paired)
2) both populations (of scores being compared) are normally distributed

Question 14

Advantage of a paired sample (dependent)

Answer 14

• groups are more equal beforehand so they give you more power
• more statistical power to find an effect
• variability due to individual differences (SD) is decreased

Question 15

-

Answer 15

• groups are more equal beforehand so they give you more power
• more statistical power to find an effect
• variability due to individual differences (SD) is decreased
• we can have smaller sample sizes

Question 16

Disadvantage of paired t-test

Answer 16

• may be harder to find participants

Question 17

___ sample t-tests are easier to conduct

Answer 17

Independent

Question 18

Independent samples are AKA

Answer 18

Independent groups, between-subjects

Question 19

Dependent samples are AKA

Answer 19

Paired samples, correlated-groups