In a Study Comparing Two Nonequivalent Groups, a Selection by History

question 12

Multiple Choice

In a study comparing two nonequivalent groups, a selection by history confound occurs when

• A)some event intervenes between pretest and posttest and affects just one of the groups
• B)some event intervenes between pretest and posttest and affects both selected groups equally
• C)selection influences one of the groups and history influences the other
• D)some historical event causes a failure of the random assignment procedure

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Definitions:

Incremental Manufacturing Cost

The extra expense associated with manufacturing an additional unit of a product.

Contribution Margin

The amount remaining from sales revenue after variable expenses are subtracted, contributing towards covering fixed costs and profit.

Variable Selling Expenses

Costs that fluctuate with the level of sales, such as commissions or shipping fees.

Variable Administrative Expenses

Expenses that vary with the level of business activity, such as sales commissions or supply costs.