Exam 12: Confidence Intervals and Effect Size: Building a Better Mousetrap

A single number that is used to predict another value is a point estimate.

A researcher is interested whether an intervention successfully decreases prejudice in majority populations. When conducting an independent samples t-test, a researcher calculates the t-statistic with an alpha level of .05, and a 95% confidence interval of the mean difference. Which of the following is most likely true?

Which of the following partial eta-squared is the closest to the cut off of a large effect?

Confidence Intervals are created for the sole purpose of estimating the true population mean.

When one is certain that an interval is a good one, one likely has high ______________.

eta-squared cannot be less than 0

A researcher is examining three different types of treatment on individuals who suffer from major depression. Below are the data, use it to answer the following questions treatment type 1 treatment type 2 treatment type 3 43 45 31 45 36 36 29 18 38 27 40 45 38 51 39 41 31 29 39 29 30 24 34 28 31 36 22 38 37 19 19 24 30 Characterize the size of this effect

Precision is best described as when the interval estimate captures the true estimated value.

If a one-way ANOVA has an eta squared of .24 means that…

Point estimates can be used to estimate which of the following values?

A research team collects data from two groups, in one group, they administered a learning task that provided feedback (i.e., telling the participant if they were right or wrong) and in the other, the participants were not provided with feedback. The research team is interested in the number of trials the participants spent learning as a function of their independent variable. Below are the number of trials each participant spent. Use it to answer the following questions. Feedback No Feedback 19 12 14 7 15 15 12 14 16 11 15 8 19 13 28 9 17 15 15 17 11 12 6 11 19 5 13 13 12 4 16 14 12 13 5 4 Calculate the 95% confidence interval of the mean difference

When calculating a Cohen's d in a dependent samples t-test what does it tell us?

Use the source table below to answer the following questions Source SS df MS F Factor 1 8819 1 Factor 2 27482 2 Factor 1 * Factor 2 17334 2 Error 55827 35 How many total eta-squared are there for this factorial ANOVA?

Confidence intervals that have higher % confidence are likely to encompass a wider range than one that has a lower % confidence.

A researcher is examining three different types of treatment on individuals who suffer from major depression. Below are the data, use it to answer the following questions treatment type 1 treatment type 2 treatment type 3 43 45 31 45 36 36 29 18 38 27 40 45 38 51 39 41 31 29 39 29 30 24 34 28 31 36 22 38 37 19 19 24 30 calculate the eta-squared

What is the relationship between effect size and statistical significance?

The 99% confidence interval of a mean difference is from .04 to 1.49. This suggests that the mean difference is significant at the alpha = .05 level.

Cohen's d can be used to estimate the size of a mean difference between two groups

In the context of ANOVA, an eta-squared is used to portray which of the following?

Suppose that the population mean for IQ is 100 with a standard deviation of 15. A researcher is testing a group 25 of talented youth. His sample has a mean of 112 with a standard deviation of 14. What is the 95% confidence interval of the mean?