PSY230 stats (exam 3 conceptual) NAU Dr. Weber Questions With Correct Solutions, Already Passed!!

You conduct a z test using an alpha level of .05two-tail (zcrit = ± 1.96). The value of zobt = -1.5. Do you reject or retain the null hypothesis? - Retain the null hypothesis Mathematically, the power of an experiment is - the probability that the results of an experiment will allow rejection of the null hypothesis if the independent variable has a real effect. You conduct a sign test and find that the calculated probability is .067. You are using an alpha level of .05two-tailed. Given this scenario, is the following statement true or false? Based on the decision rule, you should reject the null hypothesis and conclude that the independent variable has an effect on the dependent variable. - False Is the following statement true or false? A result that is statistically significant can be assumed to be important as well. - False Which of the following asserts that the independent variable does not affect the dependent variable? - The null hypothesis. Match the type of test (one- vs. two-tailed) with the hypothesis for which it is indicated. Question: The new treatment will decrease depression scores. The new treatment will have an effect on depression scores - B. One-tailed testA. Two-tailed test The hypothesis that claims the difference in results between conditions is due to the independent variable is the - alternative hypothesis This error is defined as a decision to retain the null hypothesis when the null hypothesis is false. - Type II error By making alpha more stringent, the possible outcomes which allow the rejection of H0 are _______. - decreased As the power of an experiment increases, the probability of making a Type II error ___________________. - decreases Holding other factors constant, increasing the size of the real effect will increase power. - True Holding other factors constant, increasing the sample size (N) will increase power. - True The higher the power, the more sensitive the experiment is to detect a real effect of the independent variable. - True Which of the following will increase power in the the z and t tests you've learned? - Correct Increasing the size of the real effect Correct Decreasing sample variability Correct Increasing sample size CorrectUsing a less stringent alpha level (e.g., using .05 rather than .01) (All answers are correct) Power + Beta = ___. - 1 The standard deviation (SD) of the sampling distribution of the mean is equal to __________________________________. - the SD of the raw-score population divided by the square root of N A Type I error is defined as - a decision to reject the null hypothesis when the null hypothesis is true. If the probability of getting the obtained value of the statistic is equal to or less than the alpha level, we ______________. - reject the null hypothesis In a sampling distribution, N = ______. - The size of each sample In the case of the sign test, if the independent variable had no effect, the null hypothesis population would have ___________. - an equal number of pluses and minuses. The sampling distribution of a statistic gives (check all that apply): - Correct the probability of each of the possible values of a statistic, assuming H0 is true Correct all of the values that a statistic can take The standard deviation of the sampling distribution of the mean is also known as the _________________. - standard error of the mean The ________ value of a statistic is the value of the statistic that bounds the critical region. - criticalThe mean of the sampling distribution of the mean equals _____. - μ To use the z test, the following values must be known (check all that apply): - Correct the sample mean Correct the population standard deviation Correct the sample size Correct the population mean The value of zcrit for alpha = .05two-tail is ___________. - 1.96 With alpha set to .05two-tail, the area in each tail equals ____. - 2.5% A 99% confidence interval will be narrower than a 95% confidence interval. - False