Key Stats Concepts

Question 1

What are stats and probability?

Answer 1

Stats; given the info what is in the population

Probability; given the info about the population what is the the characteristics of the person selected

Question 2

What is they relationship between true and observed value?

Answer 2

The observed value is the best estimate of the true tendency of a whole population

Question 3

What is a hypothesis?

Answer 3

Statement that an underlying truth or scientific interest takes a particular quantitive vale

Question 4

How do you do a hypothesis test?

Answer 4

Calculate probability of getting observed extreme (if hypothesis true)
Is probability very small, conclude the observation and hypothesis don’t match
Calculated value = P value

Question 5

What does rejecting the null hypothesis mean?

Answer 5

Strongly suggests that the null hypothesis is false

Question 6

What does not rejecting the null hypothesis mean?

Answer 6

We cannot accept it
By not rejecting it doesn’t mean that the null hypothesis is true
Just that findings are in line with it being true

Question 7

What is the 95% confidence interval?

Answer 7

Range in which 95% certain that the true value of underlying truth lies

Observed value is always within this interval

Question 8

How does the null hypothesis relate to the 95% confidence interval?

Answer 8

If 1 is within the range then accept the null hypothesis

If 1 not within the range then reject the null hypothesis = significant result