Title | All Notes on All Formulas/Tests |
---|---|
Author | QQ AA |
Course | Probability and Statistics for Engineers |
Institution | University of Michigan |
Pages | 4 |
File Size | 214.7 KB |
File Type | |
Total Downloads | 26 |
Total Views | 182 |
These are all the equations and "tests" that were covered in the course....
μ = population mean 𝑥 =sample mean descriptive stats describe data (graphically, numerically)
inferential stats infer about population
Frequency table → frequency/bin ranges are equal; absolute, relative or cumulative frequency # of bins ≈ √#observations (should be about 5-20-ish) no relative frequency at μ0 → β(μ') = Φ(𝑧𝛼 + 0 ) Ha: μp0 → β(p') = Φ( Ha: p≠p0 → β(p') = Φ(
)
𝑝0 −𝑝′+𝑧𝛼 √𝑝0 (1−𝑝0 )/𝑛 √𝑝′(1−𝑝′)/𝑛
𝑝0 −𝑝′+𝑧𝛼/2√𝑝0 (1−𝑝0 )/𝑛 √𝑝′(1−𝑝′)/𝑛
Sample size for β(p') → 1-tailed test n ≥ (
𝑝−𝑝0 √𝑝0 (1−𝑝0 ) ⁄𝑛
)−Φ(
Ha: p Δ0 → β(Δ ') = Φ(𝑧𝛼 −
Δ′ −Δ0
Ha: μ1 – μ2 ≠ Δ0 → β(Δ ') = Φ(𝑧𝛼/2 −
)
𝜎 Δ′ −Δ0 𝜎
(round down) Δ0 −Δ′ 𝜎𝑥−𝑦
) − Φ (−𝑧𝛼/2 −
) → n1, n2 ≥
CI: 𝑥 − 𝑦 ± 𝑡𝛼/2,𝑣 √𝜎12 /𝑛1 + 𝜎22 /𝑛2 2
(𝜎12 +𝜎22 )(𝑧𝛼 +𝑧𝛽 ) (Δ′ −Δ0 )2
Ha: μ1 – μ2 < Δ0 → β(Δ ') = 1 – Φ(−𝑧𝛼 − Δ′ −Δ 𝜎
0
)
Δ′ −Δ0 𝜎
σ = 𝜎𝑥 −𝑦 = √𝜎12 /𝑛1 + 𝜎22 /𝑛2
)
Paired t-test: usually strong positive dependence; paired t-test variance and CI are smaller/narrower than 2 sample t-test n individuals from one population; results from 2 experiments (e.g. grades of same people in 2 different classes) 𝑑 −Δ 0 H 0 : μ D = Δ0 t= v = d.f. = n-1 CI: 𝑑 ± 𝑡𝛼/2,𝑣 𝑠𝐷 /√𝑛 𝑠𝐷 /√𝑛
n1, n2 large
Compare 2 population proportions: H0: p1 – p2 = 0
z=
𝑝1 −𝑝2
Ha: p1 – p2 > 0 → β(p1,p2) = Φ(
Ha: p1 – p2 ≠ 0 → β(p1,p2) = Φ(
𝑧𝛼 √𝑝 𝑞 (
H0: 𝜎12 = 𝜎22
2
𝑛1 𝑝1 +𝑛2 𝑝2 𝑛1 +𝑛2
𝜎
)
𝜎
)−Φ(
1 1 + )−(𝑝1 −𝑝2 ) 𝑛1 𝑛2
=
#𝑠𝑢𝑐𝑐𝑒𝑠𝑠𝑒𝑠 𝑡𝑜𝑡𝑎𝑙
Ha: p1 – p2 < 0 → β = 1 – Φ( 1 1 + )−(𝑝1 −𝑝2 ) 𝑛1 𝑛2
−𝑧𝛼 √𝑝 𝑞( 2
2
(𝑧𝛼 √(𝑝1 +𝑝2 )(𝑞1 +𝑞2 )/2 +𝑧𝛽 √(𝑝1 𝑞1 +𝑝2 𝑞2 ) ) 𝑑2
𝑠2
f = 𝑠12
Ha: 𝜎12 > 𝜎22 → f ≥ Fα,v
1 1 + )−(𝑝1 −𝑝2 ) 𝑛1 𝑛2
𝑧𝛼 √𝑝 𝑞(
Sample size for a certain β → n ≥ f-test (2 variances):
𝑝 =
√𝑝𝑞(1/𝑛1 +1/𝑛2 )
2
v = d.f. = (n1-1,n2-1)
Ha: 𝜎12 < 𝜎22 → f ≤ F1-α,v
𝜎
)
𝜎 = 𝜎𝑝1 −𝑝2 = √
−𝑧𝛼 √𝑝𝑞 (
1
𝑛1
1
𝑝1 𝑞1 𝑛1
+ 𝑛 )−(𝑝1 −𝑝2 ) 𝜎
2
+ )
𝑝2 𝑞2 𝑛2
CI: 𝑝1 − 𝑝2 ± zα/2 𝜎𝑝1 −𝑝2
⇒ replace zα with zα/2 for 2-tailed test
Ha: 𝜎12 ≠ 𝜎22 → f ≥ Fα/2,v or f ≤ F1-α/2,v...