Hypothesis testing Flashcards
Parameters
Null hypothesis H₀
Alternative hypothesis H₁
Forms of H₁
H₁ : μ < μ₀ - one tail
H₁ : μ > μ₀ - one tail
H₁ : μ ≠ μ₀ - two tail
Rejectance and acceptance regions
If the sample mean is in the acceptance region you accept H₀ else you reject it
Finding the rejection region
- Determine p based on significance level
- Find corresponding z value
- set z equal to [c - μ] / [σ/√n]
- solve for c
z value may be negative depending on bell curve and context
Test statistic approach steps
- Lay out parameters
- Set up like normal distribution
- Solve for phi value
- Reject or accept H₀ by comparing value and significance level
Discrete variables
Reject null hypothesis for one tail test if probability is less than the significance level
Reject null hypothesis for two tail test if probability is less than half the significance level
Binomial AS reminder
To input binomial notation into calculator use nCr
Binomial distribution approximated to normal distribution steps
- Layout all parameters
- Show np > 5 and nq > 5
- State mean and variance using np and npq respectively
- State normal distribution
- State probability (cont correction)
- Solve for z
- Compare with signficance level
- State conclusion
Poisson distributionapproximated to normal distribution steps
- Lay out all parameters
- Ensure λ is large, > 15
- Set poisson and normal parameters
- Set probability
- Solve for z
- Compare with significance level
- State conclusion
Type 1 and Type 2 errors
Type 1 error is when a true null hypothesis is rejected, for normal distribution P(Type 1 error) = significance level of the test
Type 2 error is when a false null hypothesis is accepted, for normal distribution P(Type 2 error) = P(accept H₀ | H₀ false)
Probability of type 1 and type 2 errors with binomial distribution
Type 1:
1. set binomial parameters
2. set type 1 error parameter
3. solve binomially using condition given
4. answer is the probability
Type 2:
1. set binomial parameters
2. set type 2 error parameter
3. solve binomially using condition given and the probability given for the type 2 error
4. answer is the probability
Probability of type 1 and type 2 errors with poisson distribution
Type 1:
1. set hypothesis testing parameters
2. set type 1 error parameter
3. solve using poisson distribution and condition given
4. answer is the probability
Type 2:
1. set hypothesis testing parameters
2. set type 2 error parameter
3. solve using poisson distribution and condition given, change the λ value to what is given
4. answer is the probability
Solving steps for large samples
- lay out hypothesis testing parameters
- set p and z value according to significance level
- solve for x̄
- use x̄ to place into equation when solving for z, [x̄ - μ] / [σ/√n]
- place z value into another probability notation
- solve for the phi value, the probability
- state conclusion by comparing probaility with significance level