A two tailed hypothesis test is being uses to evaluate a treatment effect with o= .05. if the sample data produce a z- score of z= -2.24 what is the correct decision?
* reject the null hypothesis and conclude that the treatment has an effect
* fail to reject the null hypothesis and conclude that the treatment has no effect
* fail to reject the null hypothesis and conclude that the treatment has an effect
* reject the null hypothesis and conclude that the treatment has no effect
the critical boundaries for a hypothesis test are z= +1.96 and -1.96. if the z score for the sample data is z= -1.90, what is the correct statistical decision?
* reject H1
* reject Ho
* fail to reject Ho
* fail to reject H1
A researcher administers a treatment to a sample of participants selected from a population with u= 80. If a hypothesis test is used to evaluate the effect of the treatment which combination of factors is most likely to result in rejecting the hypothesis?
* a sample mean much different than 80 with o= .01
* a sample mean near 80 with o=.01
* a sample mean much different than 80 with o= .05
* a sample mean near 80 with o= .05
under what circumstances can a very small treatment effect still be significant
* if the standard error of M (oM) is very large
* if the sample size of (n) is very large
* if the sample standard deviation (o) is very large
* all of these factors are likely to produce significant results.
A sample of n=9 individuals is selected from a population with u= 60 and o=6, and a treatment is administered to the sample. after the treatment, the sample mean M= 63. What is the Cohen's d for this sample?
* 1.00
* 0.33
* 2.00
* 0.50
Which of the following is an accurate definition for the power of a statistical test?
* the probability of supporting a false null hypothesis
* the probability of rejecting true null hypothesis
* the probability of rejecting a false null hypothesis
* the probability of supporting true null hypothesis