If a Disorder Occurs Only in the Presence of Factor

question 70

Multiple Choice

If a disorder occurs only in the presence of Factor X but only when Factor Y or Factor Z are present, we might suspect that Factor X is a _____ cause of the disorder.

• A)necessary but not sufficient
• B)sufficient but not necessary
• C)necessary and sufficient
• D)neither necessary nor sufficient

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Definitions:

Regression Analysis

A statistical method used for estimating the relationships among variables, particularly the relationship between a dependent variable and one or more independent variables.

Dependent Variable

The variable in an experiment or model that is expected to change in response to changes in the independent variable.

Stepwise Regression

A method of fitting regression models in which the choice of predictive variables is carried out by an automatic procedure.

F-statistic

A ratio used in statistical analysis to determine the significance of a group of variables in a regression model.