Mean, Median, Standard deviation

Question 1

What are the two important ways to find the middle of a distribution?

Answer 1

mean and median

Question 2

Sample mean/average formula

Answer 2

x with line above it=(Sum of all x’s)/(n data values)

Question 3

population mean/average formula

Answer 3

Mu=(Sum of all x’s)/(N data values)

i can’t use fancy math symbols

Question 4

Is the population mean and the sample mean calculated the same way?

Answer 4

Yes, “Mu” and “x with a line above it” are calculated the same

Question 5

Sample mean example: Baseball players age

Answer 5

Add up all the ages of each player, then divide the number of players = the average of baseball players age

Question 6

How do you find median?

Answer 6

First, order/rank the data from least to biggest (vice versa), second find number that is at the middle point

Question 7

When finding the median, what if there are two numbers at the center?

Answer 7

Find the average of the two numbers by adding the two numbers together, then divide it by two

Question 8

How to find the mode? (Less commonly used measures of center)

Answer 8

The mode is the most common data value (Some problems don’t have a mode)

Question 9

How to find the midrange? (Less commonly used measures of center)

Answer 9

Averaging the smallest value and largest value. Add small and large values then divide by two

Question 10

What is standard deviation for?

Answer 10

It measures the amount of variation in a set of data. By variation, i mean how dispersed is the data.

Question 11

What does less variation mean?

Answer 11

Less variation signifies that a data set is more closely placed, like “1,2,3,4,5” whereas the opposite is “1,29,51,82,97” since it is more dispersed

Question 12

Find formula of standard deviation for population and sample

Answer 12

in red notebook

Question 13

Find variance formula

Answer 13

in red notebook