Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
10 Cards in this Set
- Front
- Back
- 3rd side (hint)
t-statistic
|
- requires sample Mean = M
- requires sample variance s² |
- unknown population otherwise we would use z-score
= do not have μ (population mean) or |
|
t-statistic
Procedure |
step 1 : State Hypothesis and alpha (α) level ( .05, .01)
step 2 : Locate critical region step 3 : Calculate step 4 : Make a decision Calculate Effect Size |
H₀: u = y
H₁: u ≠ y α = 0.05 critical region: df = n-1, look up t-table for either 1 or 2 tailed test with α level calculate: s² = SS / n-1(df) Sm = √ s² / n OR Sm = s / √n |
|
Degrees of Freedom
|
df = n-1
- determines how well the distribution of t approximates a normal distribution => for large values of df the t distribution will appear normal => with small values of df the distribution will appear flatter and spread out than normal distribution - describes how well the t statistic represents a z-score |
|
|
Cohen's d
|
Measure of effect size:
small, medium, large estimated Cohen's d => mean difference / standard deviation M - μ / s |
|
|
r²
|
Effect size:
percentage of variance acct'd for => r² = t² / t² + df * 100 |
|
|
Estimated standard error (Sm)
|
- used when
|
|
|
Directional hypothesis
|
- One tailed test
H₀: μ ≥ y H₁: μ < y Or H₀: μ ≤ y H₁: μ > y |
|
|
Sample variance
|
s² = SS / n-1
OR s² = SS / df |
|
|
sample standard deviation
|
s = √ SS / n-1
OR √ SS / df |
|
|
Independent measures design
|
- a research design that determines if there are differences between two separate samples (two groups)
- uses a separate group participants for each tx condition (or for each population) AKA Between-subjects design |
|