Exam 7: Hypothesis Testing With Z Tests

Jin predicts that people with highly symmetric faces will be rated as more attractive than people with less symmetric facial features.Is this hypothesis one- or two-tailed?

The statistical concept of p levels is often referred to as:

In one statistics course, students reported studying an average of 9.92 hours a week, with a standard deviation of 4.54.Treating this class as the population, what percent of students study more than 13 hours a week? (Round z score to two decimal places.)

A z test result of 1.98 would allow one to reject the null hypothesis, assuming a two-tailed test with p = 0.05.

The percentile is the:

If 28 percent of scores fall between a negative z score and the mean, then 22 percent of scores fall below that z score.

A given distribution has a mean of 50 and a standard deviation of 5.When comparing a score of 55 to this distribution of scores, the percentile rank is _____, whereas comparing a mean of 55, based on a sample of 10, to a distribution of means created from this parent population will result in a percentile rank of _____.

Assume the average height for American women is 64 inches with a standard deviation of 2 inches.What percent of groups of size 25 would have mean heights of more than 64.5 inches? (Round z score to two decimal places.)

If one rejects the null hypothesis, it means that the results of the study are important.

One rejects the null hypothesis only when:

When attempting to find a percentage associated with a z score, the second step involves looking up:

The sixth step in hypothesis testing is:

Imagine that the mean height for all Division I women's basketball programs is 69 inches with a standard deviation of 3 inches.The 2010-2011 women's basketball team at the University of Connecticut, with 10 players listed on the roster, had an average height of 71.2 inches.Using the z statistic, what percent of means would fall below that for these UConn Huskies? (Round z score to two decimal places.)

Inferential statistical analyses that are based on a set of assumptions about the underlying population are:

If a result is statistically significant, then chance is said to account for the outcome.

Because of the principle of _____, when sample sizes are at least 30, the distribution will most likely resemble a normal distribution.

In one statistics course, students reported studying an average of 9.92 hours a week, with a standard deviation of 4.54.The professor tells Mackenzie she scored at the 46th percentile.How many hours does she study per week? (Round z score to two decimal places.)

If we conduct the same study with different samples and get the same results each time, it is:

What proportion of a normal distribution corresponds to z scores less than 1.04?

If the percentage of scores falling between the mean and a z score of 0.30 is 11.79, then what is the percentage of scores falling between the mean and a z score of -0.30?