A Person Trying to Define an Ecological Community Should Remember

question 124

Multiple Choice

A person trying to define an ecological community should remember that communities

• A) cannot be studied on the basis of their biomass.
• B) do not always have clear-cut boundaries.
• C) are always similar in size.
• D) cannot be studied on the basis of energy distribution.
• E) always have approximately the same number of species.

Understand the impact of changing alpha levels on hypothesis testing.

Grasp the effect of sample size on the standard error of the difference and t-statistic values.

Apply the t-test appropriately to various research scenarios.

Understand the assumptions and conditions such as normality and equality of variances for performing a t-test for independent means.

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Definitions:

Unit Change

A measure indicating the change in outcome associated with a one-unit change in an independent variable within a statistical model.

Stepwise Regression

A procedure in regression analysis that automatically chooses the variables to be used for prediction.

Forward Selection

A stepwise regression approach where variables are sequentially added to the linear model based on their statistical significance in explaining the outcome variable.

Backward Elimination

A method in statistical model building where all variables are included at the start and then removed one by one based on some criteria.