Question

In: Statistics and Probability

6. A researcher wants to study a phenomena known to have an effect size of .50. a)...

6. A researcher wants to study a phenomena known to have an effect size of .50.

a) According to Cohen, this effect size would be described as

(1 point)

small
medium
large

Q38:

b) What power would the researcher be able to obtain if he did a two-tailed single sample t test at α = .05, with a sample size of 25? (2 points)

Q39: delta equals

Q40: Power equals

c) With the same test (and alpha at .05), how many subjects would the researcher need to obtain power of 0.95? (2 points)

Q41: delta equals

Q42: number of subjects

d) Interpret/discuss your answer to the above question. That is, what does power

equal to .95 mean in the context of testing a hypothesis? (1 point)

Q43: Interpret in words

Expert Solution

6)

a)

Cohen suggested that d= 0.5 represents a 'medium' effect size

Option B

38)

b)

we are allowed to solve one question only. already solved two here.

orchestra answered 1 year ago

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