confidence level of a statistical test?

Question

If α = 0.10, what is the confidence level of a statistical test? Based on the α level of the question to the left, what
critical value is used to form the confidence interval?

Answer 1

1.64 is the critical value for 90% confidence interval

------------------------------------------------------------------------------------------------- http://www.math.armstrong.edu/statsonline/5/5.3.2.html ----------------------------------------------------------------------------------------------------- There is the link where I found the answer. But you can use the normal distribution table. Since you want 10% confidence, that is 5% on each end. So you are looking for z-score that has 95% probability or 0.95. On the normal distribution table, reading it in reverse, the z-score value is technically 1.645, which is exactly half way in between 0.9495 and 0.9505. I would STRONGLY recommend you go look on the normal distribution table and see how this is done. That way you will know what to do when another one like this appears.