Chapter 3

Question 1

What is the mean?

It’s two symbols?

Answer 1

The average of the observations
for population it’s μ
For sample it’s x with a line on top

Question 2

What is the median?

What is it’s symbol?

Answer 2

The most middle value

M

Question 3

How do you find the position of the median?

Answer 3

(n+1)/2

Question 4

What is the mode?

What is it’s symbol?

Answer 4

The value that occurs most often in the data set
m
If there is more than one then make it 
m1=
m2=
Etc

Question 5

What is the range?

What is it’s symbol?

Answer 5

It is the largest data-the smallest data
Quickest calculation but inaccurate
Bigger the range, the more spread out the data is
R

Question 6

What is the mean deviation?

What is it’s symbol?

Answer 6

It is the sum of all the values subtracted by the mean multiplied by 1/n or N
MD

Question 7

What is the symbol for population size and sample size?

Answer 7

Population- N

Sample- n

Question 8

What is variance?

What is it’s symbol?

Answer 8

Formula in notes
Population- σ^2
Sample- s^2

Question 9

What is the standard deviation?

What is it’s symbol?

Answer 9

The square root of the variance
Population- σ
Sample- s

Question 10

What is the z score?

Answer 10

A multiple of how many standard deviations away from the mean a measurement x lies

Population
z= (x-μ)/σ

Sample
z= (x-x(line on top))/s

Question 11

How do you calculate the value of something at the 6 and 1/4 position?

Answer 11

X6 + 1/4(X7-X6)