Download Ch. 4.3 Hypothesis Testing Examples • Example 1. The total blood

Ch. 4.3 Hypothesis Testing Examples
• Example 1.
The total blood protein in a healthy adult is normally distributed
with mean 7.25 grams per decilitre and standard deviation .029
g/dl.
A particular patient is feeling sick and showing signs of an
abnormal blood protein level and is given a series of 10 blood
tests.
Her mean blood protein level is 7.233 g/dl. Test whether the
sickness is due to an abnormal blood protein level.
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Ch. 4.3 Hypothesis Testing Examples
• Example 2.
You work for an insurance company with a product whose
premiums have been calculated using the assumption that the
average claim size is $1100. You want to increase the premium,
but before you can do so, you require evidence that the claim
size has really increased.
Do the following data provide support for you?
250
320
1225
190
1700
450
480
3100
1540 2600
210
470
825
1800
1920
70
1425
1370
2520
2200
1020
1820
(Note that x̄ = 1250.227 and s = 891.93)
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Ch. 4.3 Hypothesis Testing Examples
• Example 3.
I claim that the percentage of smokers at the university is less
than 5%. In a random sample of 225 students, you find 4 of them
who said they smoked. Does this provide evidence to support
my claim?
What if this was a question about marijuana use? Would you
believe the answer?
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