What is the value of A such that P(-A < T < A) = .90 for a T random variable with 16 degrees of freedom? Answer to three decimal places.
I know I'm supposed to use a T-Table for this, and what I assume is that I divide .9 by 2 to get .45 for a single tail, but then I'm totally lost as to how to reference this in the T-table...
I know I'm supposed to use a T-Table for this, and what I assume is that I divide .9 by 2 to get .45 for a single tail, but then I'm totally lost as to how to reference this in the T-table...
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fmchris -
Actually, you want to find (1-0.9) / 2 = 0.05 in each tail.
Look up in the T-table (16 d.f.) to find an area equal to 0.05 in each tail. Depending upon the table you use, the value for T should be either +/- 1.746
Answer: A = 1.746
Hope that makes sense!
Actually, you want to find (1-0.9) / 2 = 0.05 in each tail.
Look up in the T-table (16 d.f.) to find an area equal to 0.05 in each tail. Depending upon the table you use, the value for T should be either +/- 1.746
Answer: A = 1.746
Hope that makes sense!