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One sample t-test
Hypothesis Testing
Z-Tests
Independent sample t-test
Paired sample t-test
100
This is the critical t-value associated with a sample of 25 graduate students.
What is 2.064?
100
Concluding that a treatment has an effect when it really has no effect.
What is type I error (or alpha)?
100
What is the Z-Score for a sample with a mean of 6 which is being compared to a sampling distribution with expected value = 9 and a standard error = 2?
What is z = -1.5?
100
1)This is my statistical decision if I obtain the following results after completing an independent samples t-test: t(32) = 3.231, p <.05
What is reject the null hypothesis?
100
The null hypothesis in symbols for a paired samples t-test.
What is MD = 0?
200
You use the t-statistic instead of the z-statistic when this value is not known for the population.
What is the standard deviation?
200
The critical value for creating the boundaries for the rejection region are determined by the _____________.
What is alpha level?
200
A researcher conducts a hypothesis test to evaluate the effect of an Etiquette Class on politeness. The hypothesis test produces the following results: z (65) = -2.60, p<05. Assuming that the researcher is using a two-tailed test, what is the correct conclusion? (Be specific in terms of the research question)
What is reject the null, the etiquette class does have an effect on politeness?
200
A child psychologist measures interpersonal aggression in a group of 20 5-year-olds and a group of 10 10-year-olds. She finds that the pooled variance (sp2 ) for these samples is 100. This is the value of the standard error of the mean (sm1-m2).
What is 3.873?
200
This is the degrees of freedom for a sample of 10 students whose attitudes about ethnic violence are measured before and after watching Schindler’s List.
What is 9?
300
This is the standard error for a sample of 100 kittens with a mean of 5 purrs and standard deviation of 2 purrs per day.
What is .20?
300
When conducting a two-tailed hypothesis test, with an alpha = .01, this would be the proportion of scores which fall the rejection region on the right-hand side of the distribution.
What is 0.005?
300
Sometimes a Z-test will not be statistically significant simply because there is a small sample size. We might instead use a test of _________________ to examine how strong the effect really is.
What is Effect Size (or Cohen’s D)?
300
A researcher is examining the relationship between liking the color pink and gender. She finds that average like of the color pink among a sample of 10 men is 4 units and the average like of the color pink among a sample of 10 women is 2.5 units. She conducts an independent samples t-test and finds the following: t(18) = 2.945. This is what she should conclude about gender and liking the color pink.
What is men like the color pink more than women?
300
Name two of the “pros” of conducting paired samples t-test.
What are need fewer subjects, can study changes over time, reduces the influence of individual differences, and much easier to get significant results?
400
If I obtain a Cohen’s d value of 0.5 it means that my sample mean is 0.5 ________________ away from the population mean.
What is standard deviation units?
400
A researcher wants to see if there is a relationship between the number of comments made on someone’s Facebook wall and their self-esteem. They found that r (60) = .456, p = .002. The researcher can conclude that _____________. (Be specific in terms of the research questions)
What is: Reject the null, the more comments on someone’s Facebook wall, the higher their self-esteem?
400
A sample of 25 lifeguards from Fort Lauderdale are asked to report how many times they have seen dolphins swimming in the ocean this summer, and their mean response = 8. Researchers first compare this sample to the population of lifeguards in the US which have a mean = 6, SD = 3. Researchers also compare this sample to the population of life guards in the Dominican Republic which have a mean of 6, SD = 1. In which scenario is there a greater chance of finding a significant difference?
What is comparing Ft. Lauderdale to the Dominican Republic?
400
This is the reason why we “pool” the variance to calculate the standard error of the mean in an independent samples t-test.
What is it allows the sample with the larger size to carry more weight?
400
A researcher finds that the mean difference (mD) in headaches that a sample of 100 women experience one month before and one month after pregnancy is 5. The standard error of the mean of differences (smD) is 4. What is the value of t for this sample & what should the researcher conclude about headaches before and after pregnancy?
What is t = 1.25 and women do not experience a different number of headaches before and after pregnancy?