# Udemy DS - Hypothesis Testing Flashcards

What are the 4 steps in data driven decision making?

1) Formulate a hypothesis

2) Find the right test

3) Execute the test

4) Make a decision

What is a hypothesis?

it is an “ idea that can be tested “

A proposed explanation or supposition, based on limited evidence, as a start point for further investigation

What is the name for the hypothesis to be tested?

The ‘Null Hypothesis’

The status-quo. Everything believed until now that is being contested with our test

What is the test that is testing the Null Hypothesis?

The ‘Alternative Hypothesis’ (H1 or HA)

It is the change or innovation that is contesting the status-quo.

Usually the alternative is our own opinion

Why test by the alternative hypothesis?

If the null is the status-quo (i.e., what is generally believed), then the act of performing a test, shows we have doubts about the truthfulness of the null.

More often than not the researcher’s opinion is contained in the alternative hypothesis.

When testing hypotheses, what are the two decisions you can make?

1) to accept the null hypothesis or

2) to reject the null hypothesis.

To ACCEPT the null means that there isn’t enough data to support alternative hypothesis.

To REJECT the null means that there is enough statistical evidence that the status-quo is not representative of the truth.

what is this symbol called and what does it denote? µ

µ is pronounced ‘ mu ‘

It denotes ‘ the mean’ or average.

It is used in hypothesis testing for the the hypothesised mean