Day 19: Normal Curve & Standard Deviation

Why do statisticians use z-scores? Check all that apply.

• To determine if data is Normal

• To compare data with different numerical scales

• To find the % of data that is greater or lesser than this point

• To find a measure of central tendency

How can you tell if data is normal? Check all that apply.

• It seems realistic

• Its mean, median, and mode are within 1 standard deviation of each other

• Its histogram is a bell shape

• Its boxplot has equal length whiskers

What is Standard Deviation?

• A measure of central tendency

• A measurement of how much data varies

• A measurement of how much data varies from the average

Tags

CCSS.HSF-LE.A.1B

Which measure goes in the center of the Normal Curve?

• standard deviation

• mean

• median

• mode

Tags

CCSS.HSS.ID.A.4

CCSS.HSS.MD.A.2

TRUE or FALSE: There are two types of standard deviation: population and sample.

• True

• Sometimes true, sometimes false

• False

Which 2 measures do you need to find the Normal Range?

• mean and median

• median and mode

• median and standard deviation

• mean and standard deviation

TRUE or FALSE: The Normal Range gives the low and high ends of what's normal for 68% of data.

• True

• Sometimes true, sometimes false

• False

Which is the Empirical Rule we learned about?

• 16 - 34 - 95%

• 34 - 95 - 99%

• 68 - 95 - 99.7%

How can you find the EXACT mean of a data set? Check all that apply.

• Use a graphing calculator and use the x-bar value

• Use the online stats calculator and use the "mean" value

• Add up all the numbers and divide by the number of numbers

How can you find the EXACT standard deviation from a sample?

• Use the very long formula

• Use the online stats calculator and use "standard deviation"

• Use the online stats calculator and use "sample standard deviation"