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A teacher wants to know whether the children in her class are performing significantly better on a standardized math test compared to the national average. The national mean score is μ = 85, the national standard deviation is σ = 25, and the mean score in her class (n = 25) is M = 92.5. Use α = .05. What is the z-score for this sample mean?

For a normal population with µ = 40 and σ = 10 which of the following samples has the highest probability of being obtained?

Scores on the SAT form a normal distribution with a mean of µ = 500 with σ = 100.  If the state college only accepts students who score in the top 60% on the SAT, what is the minimum score needed to be accepted?

Anna has 25 jellybeans in a bag. 5 are red, 3 are yellow, 7 are green, and 10 are purple. If Anna picks 4 jellybeans out of the bag without replacing them, and 1 is red, 1 is green, and 2 are purple, what is the probability she picks a yellow jellybean on her next draw?

A random sample of n = 4 scores is obtained from a population with a mean of 80 and a standard deviation of 10.  If the sample mean is M = 90, what is the z-score for the sample mean?

Which of the following is an accurate definition for the power of a statistical test?

A sample of n = 16 scores is selected from a population with µ = 100 and σ = 32.  If the sample mean is M = 104, what is the z-score for this sample mean?

A normal distribution has a mean of µ = 100 with σ = 20.   If one score is randomly selected from this distribution, what is the probability that the score will have a value between X = 80 and X = 100?

When alpha = .01 and a researcher rejects the null hypothesis, we can conclude that the sample outcome ______________.

Imagine that you conducted a hypothesis test examining how automobile ownership (i.e., someone owns an automobile or does not own an automobile) affects happiness (measured by a survey). You found that people who do not own automobiles tend to be significantly happier than those that do own an automobile. You then computed the effect size, d = 0.75. a) Why is it important to compute an effect size? b) Please interpret the Cohen’s d value (d = 0.75) by explaining what it means in terms of automobile ownership and happiness.