A sample of n = 25 scores has a mean of M = 68. Find the z-score for this sample: a) if it was obtained from a population with u =60 and sigma = 10 b) if it was obtained from a population with u =60 and sigma = 20 c) if it was obtained from a population with u = 60 and sigma= 40

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Q: I have a z statistic of 2.91 from a one tailed test. What is my p value?

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A: Solution

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A: E(S2) = (n-1/n)* sigma2  =! Sigma2  So it is biased estimator for sigma2

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Q: Ackerman and Goldsmith (2011) report that students who study from a screen (phone, tablet, or…

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A: Given Information:  t(25) = 2.071 here,  df = 25  t value = 2.071

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A: We have to find critical value.

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A: Here,      X1  is mean of r.s  of size n  from Nμ, σ12  &amp;  X2  is mean of r.s of size   n…

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Q: In a test of Ho: H= 100 against H:u 100, a sample of size 10 produces a sample mean of 103 and a…

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Q: To test H0: μ = 50 versus H1: μ < 50, a random sample of size n = 24 is obtained from a population…

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Q: If all other values are held constant, what happens to the value of t when sample size increases ?

A: The formula to calculate t value (test statistic) can be written as:

Q: A population has a u=50 and o=10. If these scores are transformed into z- Scores, the population of…

A: Given that mean =  E(X) = 50 and SD(X) = 10, then  Var(X) = 102 = 100

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