Day 6 Two Way Frequency Tables Conditional.notebook
November 16, 2016
Date: 11/16
Objective: I can represent categorical data using a two­way frequency table
You should be
writing this in your notebook.
Entry: A public opinion survey
explored the
relationship between
age and support for
increasing the minimum
wage. The results are
summarized in the two­
way table to the right.
Unfortunately we forgot to write down some of the joint and
marginal frequencies. Fill in the blanks using what we do have.
Vocabulary
Conditional Relative Frequency
the ratio of a joint relative frequency and a related marginal relative frequency.
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Day 6 Two Way Frequency Tables Conditional.notebook
November 16, 2016
Exercise 1
Let’s see if there is a connection between eye color and hair
color by using conditional relative frequencies.
A What is the conditional relative
frequency of having green eyes if
you have red hair? (This is
equivalent to asking what the
percent of people with red hair
have green eyes.)
B What is the conditional
relative frequency of
having green eyes if
you have black hair?
C
Does it appear that having green eyes has a dependency or
at least an association with having red hair? Explain.
D Is it more likely that a person with black hair has blue eyes or
that a person with blond hair has brown eyes?
Use conditional marginal frequencies to support your
answer.
Exercise 2
A survey of 52 graduating seniors was conducted to determine if
there was a connection between the gender of the student and
whether they were going on to college. Based on this data, what is
more likely: that someone going to college is female or that
someone who is female is going to college? These may seem like
the same thing, but are quite different.
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Day 6 Two Way Frequency Tables Conditional.notebook
November 16, 2016
Exercise 3
You randomly survey students in your school regarding whether own a cell
phone, mp3 player or both. You find that 78 students own a cell phone and of
those 57 own a mp3 player. There are 13 students that do not own a cell phone
but own an mp3 player. 9 students own neither device. Construct a two ­ way
table for this data.
A. What percent of students own a cell phone?
B. What percent of students own an mps player?
C. What percent of students own a cell phone
given they have a mp3 player?
D. What percent of students own a mp3 player
given they don't own a cell phone?
Exercise 4
The table shows the counts of earned degrees for several colleges on the East
coast. The leve of degree and the gender of the recipient were tracked.
A. What is the probability that a randomly selected
recipient of a doctorate degree is female?
B. What is the probability that a randomly selected
male degree recipient earned a professional
degree?
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Day 6 Two Way Frequency Tables Conditional.notebook
November 16, 2016
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