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Which of the following accurately describes the effect of increasing the sample size?

Which combination of factors will increase the chances of rejecting the null hypothesis?

Which of the following accurately describes a hypothesis test?

What proportion of a normal distribution is located in the tail beyond z = 2.14?

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 = 1.25. a) Why is it important to compute an effect size? b) Please interpret the Cohen’s d value (d = 1.25) by explaining what it means in terms of automobile ownership and happiness.

A sample of n = 16 scores is obtained from a population with µ = 50 and σ = 16.  If the sample mean is M = 54, then what is the z-score for the sample mean?

John drives to work each morning and the trip takes an average of 38 minutes.  The distribution of driving times is approximately normal with a standard deviation of 5 minutes.  For a randomly selected morning, what is the probability that John’s drive to work will take less than 35 minutes?

What proportion of a normal distribution is located between the mean and z = –0.40?

A jar contains 10 red marbles and 30 blue marbles.  A random sample with replacement of n = 3 marbles is selected from the jar.  If the first two marbles are both blue, what is the probability that the third marble will be red?

A sample of n = 100 scores is selected from a population with µ = 80 with σ = 20.  On average, how much error is expected between the sample mean and the population mean?