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Explain the difference between a left-tailed, two-tailed, and right-tailed test. When would you choose a two-tailed test? How might you tell the direction of the test by looking at a pair of hypothesis? How might you tell which direction (or no direction) to make the hypothesis by looking at the problem statement (research question)?
The direction of the test is indicated by the alternate Hypotheses H1. < indicates a left tailed test and > indicates a right tailed test. One would choose a two tailed test when the direction of < or > does not matter to the researcher. Two tailed tests are indicated by =. One would also choose a two tailed test if the rejection of the two tailed test guarantees a rejection of the left or right tailed test. I think one can tell which direction the hypothesis should be by the way the research question is worded. Certain words can mean less than or greater than;: or equal to or not equal to; or greater than or equal to some number. One just needs to read the hypothesis carefully to make sure he or she is conducting the test in the correct direction or the test will be done wrong. An example of this would be where the average means of monthly wages for a population area is $1,800 and someone questions this saying they believe it is higher for the particular area. So the hypothesis for this particular scenario would be written out as: H0 : µ > 1,800 H1 : µ ≤ 1,800

Please try to respond to this question by at least Friday of Week 1, and interact with your classmates’ responses going forward as well.
5 - Why is statistical significance not necessarily of practical important difference to a business decision? Provide an example and explain. Why do statisticians play only a limited role in deciding whether statistical significance requires a business action?

4 - Explain the difference between the null

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