Year 2 - Chapter 1 w/ Regression, Correlation and Hypothesis Testing

Question 1

Transform this log

y = ax^n

into its straight-line form.

Answer 1

✯ log y = log a + n logx

Where n = Gradient.
Where log a = y intercept.

Question 2

Transform this log

y = ax^x

into its straight-line form.

Answer 2

✯ log y = log a + x logx

Where log x= Gradient.
Where log a = y intercept.

Question 3

What is the PMCC?

Answer 3

✯ The PMCC measures the test and strength between two variables.

Question 4

How do we find PMCC (r) on graphical calc?

Answer 4

✯ Statistics > Input table values > Calc > Reg > X > Ax+b

Question 5

Where can I find the PMCC table?

Answer 5

✯ In the formula booklet, named ‘Critical Values for Correlation Coefficients.’

Question 6

Tell me the five , step method when hypothesis testing for zero correlation.

Answer 6

1. State H0 and H1
2. Use significance level and sample size to find the critical value using the PMCC table.
3. Draw a diagram then shade the critical region.
4. If r is in the critical region: Reject H0 and Accept H1

or..

If r is not in the critical region: Accept H0 and Reject H1

5. Write a conclusion in context.

Question 7

A perfect straight line; value of r?

Answer 7

1

Question 8

A moderately straight line; value of r?

Answer 8

0.8

Question 9

Not a straight line; value of r?

Answer 9

0

Question 10

Some of them in a straight line; value of r?

Answer 10

0.3