SASA Quiz #2

You got a p-value of 0.09. What conclusion can you derive?

• This is statistically significant at the 95% and 99% confidence levels.

• This is statistically significant at the 90% significance level and insignificant at 95% significance level.

• This is statistically insignificant at the 95% significance level.

• This is statistically significant at the 99% significance level.

1. Suppose data from a demographic survey indicated that the mean height of Europeans is 69.9 inches with a standard deviation of 2.8 inches. Meanwhile, suppose that the mean height of Asians is 63.7 inches with a standard deviation of 2.7. Suppose further that the height of a Spanish professional tennis player is 72.8 inches, and the height of a Japanese professional tennis player is 70.7 inches. What conclusion can be inferred from the given information?

• 1. The Japanese player is taller than the Spanish player.

• The Spanish and Japanese players have the same heights.

• 1. The Spanish player is taller than the Japanese player.

• 1. The heights are incomparable due to their different nationalities. 

1. The average grade on a statistics test was 78 with a standard deviation of 8. Assume that test scores are normally distributed. What is the probability that a student gets a score more than 80?

• 1. 0.0122

• 1. 0.4013 Use standard z table or =NORMSDIST().

• 1. 0.9878

• 1. 0.5865

1. Which of the following will lead to the rejection of the null hypothesis?

• 1. The p-value is 0.05 for a 99.9% confidence level.

• 1. The z test statistic is less than the critical value under a one sample test of population means.

• 1. The t test statistic is greater than the critical value under a one sample test of population means.

• 1. The significance level is greater than the test statistic. 

1. What does it mean when the p-value is 0.000?

• 1. We have all the evidence to reject the null hypothesis.

• 1. We have no evidence to reject the null hypothesis.

• 1. We have some evidence to reject the null hypothesis

• We have all the evidence to accept the null hypothesis.

Because the primary goal of inferential statistics is to generalize from a population to a sample, the larger the sample size, the better.

• TRUE

• FALSE

A hypothesis is a statement about the population that must be tested using a sample.

• TRUE

• FALSE

We have a left-tailed/lower tailed alternative hypothesis if it states that the parameter is less than the value claimed in the null hypothesis.

• TRUE

• FALSE

A Type I error is not rejecting the alternative hypothesis when the null hypothesis is true.

• TRUE

• FALSE

Suppose the computed z score in a one-sample, upper-tailed hypothesis test is 2.65. You can reject the null hypothesis at a 90% confidence level.

• TRUE

• FALSE