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Chapter 10: Q. 68 (page 659)

There are two common methods for measuring the concentration of a pollutant in fish tissue. Do the two methods differ on average? You apply both methods to a random sample of 18carp and use

(a) the paired t-test for 渭d.

(b) the one-sample z test for p.

(c) the two-sample t-test for渭1-渭2

(d) the two-sample z test for p1-p2

(e) none of these.

Short Answer

Expert verified

Apply both methods to a random sample of 18 carp and use option (a) the paired t-test for 渭d.

Step by step solution

01

Given information

The two common methods for measuring the concentration of a pollutant in fish tissue.

Random sample=18carp

02

Explanation

One proportion: one-sample z test/interval

Two proportion: two-sample z test/interval

One mean: one-sample t-test/interval

Mean difference: two-sample t-test/interval

Two means or mean differences with paired data in the two samples: paired t-test/interval

Use a test if you want to test for a difference, equality, increase or decrease. Use an interval if you want to estimate an interval in which the true value lies.

Paired t-test for渭d.

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Researchers are interested in evaluating the effect of a natural product on reducing blood pressure. This will be done by comparing the mean reduction in blood pressure of a treatment (natural product) group and a placebo group using a two-sample t-test. The researchers would like to be able to detect whether the natural product reduces blood pressure by at least 7points more, on average than the placebo. If groups of size 50are used in the experiment, a two-sample t-test using role="math" localid="1650436089340" 伪=0.01will have a power of 80%to detect a 7-point difference in mean blood pressure reduction. If the researchers want to be able to detect a 5-point difference instead, then the power of test

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The Minitab output below gives a 95% con铿乨ence interval for p1-p2. Interpret this interval in context. Then explain what additional information the con铿乨ence interval provides.
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