Statistics Notes – Day 4
I. Vocabulary

Mean Absolute Deviation
o A measure of the _________________ of data.
o Formula:

Standard Deviation:
o A measure of the _________________ of data.
o The larger the standard deviation is, the ______________________________ the
numbers tend to be from the mean.
o Formula:

Mean Absolute Deviation and Standard Deviation
o Statistics that are used to measure the ___________________ of data
o Standard Deviation is a ______________________________ way to measure the
spread of data.
o Mean Absolute Deviation may be a better way to measure the dispersion of data when
there are _______________________ since it is less affected by
__________________.

Z-Score
o A z-score (or _______________________________) indicates ___________________
standard deviations a data point is __________________ or __________________ the
mean of a data set.
o
o
o
o

A positive z-score indicates that a data point is _____________________________
A negative z-score indicates that a data point is _____________________________
A z-score of zero indicates that a data point is ______________________________
Formula:
Variance
o A measure of the _________________________ of the data
o It is used to find the ______________________________ and is equal to the
________________________________________________________.
o Formula:
II. Normal Distributions
 A normal curve is ________________________ about the __________________ and has a
_____________________ shape.


Empirical Rule
o In a normal distribution with mean  and standard deviation  :
 ____________________ of the data fall within 1  of the mean 
 ____________________ of the data fall within 2  of the mean 
 ____________________ of the data fall within 3  of the mean 
III. Application
1) Light Bulbs
2) Basketball Player Heights
Chicago 77”
Bulls
Toronto 79”
Raptors
81”
79”
77”
81”
79”
76”
82”
83”
69”
78”
84”
79”
79”
80”
84”
81”
83”
71”