Increase the difference between the means eg stronger

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Increase the difference between the means (eg stronger manipulation) Decrease the standard deviation Increase the sample size Use a more lenient (a) alpha level
4. a. Calculate Cohen’s d for the new math teaching method: Previously, we examined the effect of a new method for teaching math. The national average for a math exam is 85.00 with a standard deviation of 7.00. A class of 35 students taught with the new method averaged a 90.00 on the exam.
b. Using the general conventions for Cohen’s d
c. What does this Cohen’s d
5. a. Calculate Cohen’s d for the directional test examining if posting lectures increases test scores.
Name/#: __________________
b. Using the general conventions for Cohen’s d
c. What does this Cohen’s d
6. a. We want to know how much on average people spend on their electric bill. We gather a sample of 20 households that spend a mean of \$65.00. We know that the standard deviation of people’s electric bills is \$12.00. But what is the actual population mean? Calculate the 95% confidence
b.
7. Calculate the 95% Confidence Interval for the population mean if we obtain a sample mean of
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