An Experiment Was Conducted to See How People with Eating

question 9

Multiple Choice

An experiment was conducted to see how people with eating disorders differ in their need to exert control in different domains.Participants were classified as not having an eating disorder (control) ,as having anorexia nervosa (anorexic) ,or as having bulimia nervosa (bulimic) .Each participant underwent an experiment that indicated how much they felt the need to exert control in three domains: eating,friendships and the physical world (this final category was a control domain in which the need to have control over things like gravity or the weather was assessed) .So all participants gave three responses in the form of a mean reaction time; a low reaction time meant that the person did feel the need to exert control in that domain.The variables have been labelled as group (control,anorexic,or bulimic) and domain (food,friends,or physical laws) .Looking at the output below,what can we conclude about the group × domain interaction effect?

• A)The domain × group interaction was not significant,indicating that the degree to which people felt the need to exert control in a particular domain depended on whether they were anorexic,bulimic or a control participant,F(4,54)= 3.27,p > .05.
• B)The domain × group interaction was significant,indicating that the degree to which people felt the need to exert control in a particular domain was the same in anorexic,bulimic and control participants,F(3.10,41.89)= 3.27,p < .05.
• C)The domain × group interaction was not significant,indicating that the degree to which anorexic,bulimic and control participants felt the need to exert control in a particular domain was the same in the food,friends and physical law domains,F(2,27)= 3.27,p = .053.
• D)The domain × group interaction was significant,indicating that the degree to which people felt the need to exert control in a particular domain depended on whether they were anorexic,bulimic or a control participant,F(3.10,41.89)= 3.27,p = .029.

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Definitions:

Constituency

A body of voters in a specified area who elect a representative to a legislative body.

Significance Level

The probability of rejecting the null hypothesis when it is actually true, often denoted by alpha (α) and used as a threshold in hypothesis testing.

Percentage Points

A unit for the difference of two percentages, reflecting the absolute difference between them.

Variance

A measure of the dispersion of a set of data points around their mean value.