MATLAB: An Introduction with Applications
6th Edition
ISBN: 9781119256830
Author: Amos Gilat
Publisher: John Wiley & Sons Inc
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Transcribed Image Text:7.55 What is wrong? In each of the following situations,
identify what is wrong and then either explain why it
is wrong or change the wording of the statement to make
it true.
(a) A researcher wants to test Ho: x₁= x₂ versus the two-
sided alternative Ha: X₁ X₂.
(b) A study recorded the IQ scores of 100 college
freshmen. The scores of the 56 males in the study were
compared with the scores of all 100 freshmen using the
two-sample methods of this section.
(c) A two-sample t statistic gave a P-value of 0.94.
From this, we can reject the null hypothesis with 90%
confidence.
(d) A researcher is interested in testing the one-sided
alternative Ha: ₁ <₂. The significance test gave t = 2.15.
Because the P-value for the two-sided alternative is 0.036,
he concluded that his P-value was 0.018.
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