Hypothesis Testing 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
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 7 steps to carrying out a hypothesis test?
- dtermine if it is a one tail ot two tailed test
- define the test statistic and the parameters (probaility) that you want to investigate
- define the null and alternate hypotheses
- accurately calculate the test statistic
- compare the test statistic to the theoretical probaility
- decide whether the evidence supports or rejects the null hypotheisis
- write a conculsion in context, refernecing a defined parameter
What is the notation for null and alternate hypothesis
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
How does the critical value vary for positive and negative tails ?
Positive : value after the first that exceeds 95%
Negative: the first value that goes under the significance level
What is the actual significance level?
The actual probability of being in the critical region
What is the actual significance level?