Stats 4 - HT for Proportion (including calculation of the Critical Region) Flashcards
What is a hypothesis?
A statement made about the value of the population parameter that we wish to test by collecting evidence in the form of a sample
What is the null hypothesis?
H0 the default position- nothing has changed unless proven otherwise
* the value that you’d expect
eg: the coin is fair p=0.5
Wha is the alternate hypothesis?
H1: there has been some change in population parameter
eg: the coin is biased towards heads p>0.5
What is a test statistic?
- the evidence from the sample
Test statistic X is what we observed
Eg: the number of heads seen in 10 throws
a distribution
what is the level of significance ?
the maximum probability where we could reject the null hypothesis (or, equivalently, represents the chance of incorrectly rejecting H0)
what is a hypothesis test?
using statistical techniques to test a particular claim ot theory
what is the p value?
the probability that you obtain a value as extreme as the test statistic
what are the main steps in carrying out a hypothesis test for a population proportion?
- define the null & alternative hypotheses
- determine if it is a 1-tail or a 2-tail test
- always assume H0
- describe the associated binomial model
- identify/calculate the test statistic (TS)
- if the TS is on the LHS, find “at most”
if the TS is on the RHS, find “at least” - calculate the p-value
- compare p-vale and significance level
- accept or reject H0
- interpret the conclusions in context
What is the critical region?
The range of values of the test statistic that would lead you to rejecting H0 (null hypothesis)
What is the critical value?
The values on the boundary of the critical region
What is the actual significance level?
The actual probability of being in the critical region
What is the actual significance level?