Confidence Intervals for One Population Proportion

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Confidence Intervals for One Population Proportion
Consider a population that may or may not have a
certain attribute Population proportion p the
percent of the population that has the certain
attribute. Sample proportion the percent
of the sample that has the certain attribute.
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Confidence Intervals for One Population Proportion
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Hypothesis Tests for One Population Proportion
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Hypothesis Tests for One Population Proportion
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Hypothesis Tests for One Population Proportion
An American Roulette Wheel has 18 red, 18 black,
and 2 green slots. If after 200 spins the ball
landed on red 93 times. At the 10 significance
level, do the data provide sufficient evidence to
conclude that the ball is not landing on red the
correct percentage of the time for a balanced
wheel?
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Hypothesis Tests for One Population Proportion
Since both are at least 5, we can employ the
One-Sample z-test.
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Hypothesis Tests for One Population Proportion
Step 6 At the 10 level the data do not provide
sufficient evidence to conclude that red is not
coming up the appropriate percentage of the time.
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Hypothesis Tests for One Population Proportion
Problem 12.37 P625.
One-Sample z-Test
Since both are at least 5, we can employ
procedure 12.2, One-Sample z-Test
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Hypothesis Tests for One Population Proportion
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Hypothesis Tests for One Population Proportion
The test results are statistically significant at
the 5 level, the data do provide sufficient
evidence to conclude that the majority of
Generation Y Web users use the internet to
download music.
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Hypothesis Tests for Two Population Proportion
Problem 12.51 P638.
Two-Sample z-Test
Population 1 Women who took multivitamins
containing folic acid.
Population 2 Women who took trace elements
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Hypothesis Tests for Two Population Proportion
Step 3
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Hypothesis Tests for Two Population Proportion
The test results are significant at the 1 level,
that is, at the 1 significance level , the data
do provide sufficient evidence to conclude that
the women who take folic are at lesser risk of
having children with major birth defects.