Exam 6: Independent Groups Designs

Researchers manipulated exposure to body images by randomly assigning young girls to one of three conditions.They observed that young girls' body dissatisfaction was greatest after viewing very thin images of a Barbie doll compared to normal-weight images ("Emme" doll)or neutral images.The alternative explanation that girls in the Barbie condition might have weighed more prior to exposure to body images can be ruled out because the researchers

A researcher was interested in whether divorce and remarriage influence the extent to which children are sociable.At a nearby school,the researcher classified 5^th-graders into one of three groups: intact parents (no divorce),divorced (single-parent families),and remarried parents.The researcher interviewed the 5^th-graders and rated their sociability,and also asked them to complete a questionnaire that assessed their level of comfort in different social situations. Describe the dependent variable(s)in this study.

We can be confident that the population means differ for two conditions of an experiment when the confidence intervals for the two sample means

In order to conduct an experiment more efficiently,a researcher tests groups of participants in several small groups.The number of participants in each group differs because of participants' availability at different times.The different number of participants in each group represents a potential

A statistically significant outcome is an outcome that

A researcher randomly assigns one classroom to a new teaching method and a second classroom to the control condition (the regular teaching method).This researcher faces the potential problem of confounding due to

A researcher read a research report indicating that a certain medication was found to be effective when tested on men.The researcher plans to do an experiment testing the effectiveness of the same medication,but in his experiment both men and women will be tested.The researcher is planning to do a

Which of the following is the most critical problem in drawing causal inferences based on the natural groups design?

________ refers to the researcher's ability to make causal inferences regarding an experimental outcome and _________ refers to the researcher's ability to generalize the findings beyond the scope of the specific experiment.

If participants know they have been given alcohol in an experiment,they may expect certain effects such as giddiness or relaxation.The general term for such cues that guide participants' behavior in a study is

.The researcher should

Four students plan to conduct an experiment with four conditions (A,B,C,and D)during one semester.Each student will serve as an experimenter.The best way to control for the extraneous variable of having four experimenters test participants in the study is to

When we conclude that an experiment does not provide sufficient evidence to reject the null hypothesis when,in fact,an independent variable does produce an effect,the inferential statistics problem is called a

Which of the following is an example of an individual differences (subject)variable?

Explain how the procedures for conducting a matched groups design and a natural groups design differ from the random groups design.

A researcher tested whether exposure to images of very thin fashion models causes young women to be dissatisfied with their own body,compared to exposure to athletic body images or neutral (non-body)images.She randomly assigned 120 women from an introductory psychology course to one of three exposure conditions: very thin female images,athletic female images,or neutral images (e.g.,household objects).Each condition had 10 images,projected individually on a large screen.The young women participated in small groups.Each image was displayed for 1 minute,for a total of 10 minutes of exposure.After viewing each image,participants wrote for 30 seconds a description of the image (the participants were led to believe their memory was being tested).After viewing the images,the women completed a questionnaire about satisfaction with their body.Negative scores indicate body dissatisfaction and positive scores indicate satisfaction with their body.The mean scores for each condition were as follows: Suppose the .95 confidence interval (CI)for the very thin condition is -1.75 to -2.50; the CI for the Athletic condition is -.75 to -1.25; and the CI for the neutral condition is 0 to .50.What claim would you make based on the estimates of the population means for the three groups in the experiment based on a comparison of these confidence intervals?

The problem of Type I and Type II errors occurs because

A researcher tested whether exposure to images of very thin fashion models causes young women to be dissatisfied with their own body,compared to exposure to athletic body images or neutral (non-body)images.She randomly assigned 120 women from an introductory psychology course to one of three exposure conditions: very thin female images,athletic female images,or neutral images (e.g.,household objects).Each condition had 10 images,projected individually on a large screen.The young women participated in small groups.Each image was displayed for 1 minute,for a total of 10 minutes of exposure.After viewing each image,participants wrote for 30 seconds a description of the image (the participants were led to believe their memory was being tested).After viewing the images,the women completed a questionnaire about satisfaction with their body.Negative scores indicate body dissatisfaction and positive scores indicate satisfaction with their body.The mean scores for each condition were as follows: Describe the dependent variable(s)in this study.

A researcher tested whether exposure to images of very thin fashion models causes young women to be dissatisfied with their own body,compared to exposure to athletic body images or neutral (non-body)images.She randomly assigned 120 women from an introductory psychology course to one of three exposure conditions: very thin female images,athletic female images,or neutral images (e.g.,household objects).Each condition had 10 images,projected individually on a large screen.The young women participated in small groups.Each image was displayed for 1 minute,for a total of 10 minutes of exposure.After viewing each image,participants wrote for 30 seconds a description of the image (the participants were led to believe their memory was being tested).After viewing the images,the women completed a questionnaire about satisfaction with their body.Negative scores indicate body dissatisfaction and positive scores indicate satisfaction with their body.The mean scores for each condition were as follows: What type of experimental design did this researcher use?

Describe briefly how confidence intervals can be used to determine if the means for the two conditions of an experiment differ.