Past costs, often referred to as sunk costs, are expenditures that have already been incurred and cannot be recovered or altered by any decision made in the present or future. Because they remain the same regardless of which alternative is chosen, they are considered irrelevant for decision-making purposes and should be ignored to avoid biased or incorrect financial conclusions.

In activity-based costing, indirect costs are grouped into cost pools based on the activities that drive those costs. While traditional systems might use a single plant-wide rate, ABC refines this by using multiple cost pools to better reflect the diversity of activities. Using one or two cost pools is a simplified version of this allocation process compared to more complex multi-pool systems.

Organizations use various transfer pricing methods to ensure fair internal transactions. Market-based pricing uses external market rates for comparison. Cost-based pricing relies on production costs, including markups. Negotiated pricing involves direct bargaining between division managers. Using a combination of these methods allows companies to balance divisional autonomy with overall corporate profitability, ensuring that internal transfers reflect economic reality and support accurate performance measurement across different business units.

The flexible budget variance is the difference between the flexible budget amount and the actual result. It is a key performance indicator that helps management identify inefficiencies or savings by comparing actual performance against a budget that has been adjusted for the actual level of activity achieved during the reporting period.

Product-cost cross-subsidization occurs when a company misallocates costs, leading to the underpricing of one product and the overpricing of another. This often happens when indirect costs are allocated using a single, inaccurate base, causing products that consume fewer resources to subsidize those that consume more, thereby distorting the true profitability of individual product lines.

In regression analysis, the residual represents the difference between the observed value and the value predicted by the model. It is interchangeably referred to as the error term or the disturbance term, as it accounts for the unexplained variance in the dependent variable.

Multiple regression is a statistical technique used to model the relationship between a single dependent variable and two or more independent variables. By including multiple predictors, the model can account for various factors influencing the outcome simultaneously, providing a more comprehensive analysis of complex business scenarios where a single variable is insufficient to explain the variance in the dependent variable.

Demand inelasticity occurs when the percentage change in quantity demanded is less than the percentage change in price. This means consumers are not very sensitive to price changes for that specific product. This is often observed in essential goods or products with few substitutes, where consumers continue to purchase the item regardless of price increases.

The break-even and target profit analysis formula requires dividing the total fixed costs plus the desired target profit by the contribution margin per unit. The contribution margin represents the amount remaining from sales revenue after variable costs are covered, which then contributes toward covering fixed costs and generating profit. This is a fundamental concept in Cost-Volume-Profit (CVP) analysis.

The contribution margin is defined as the excess of sales revenue over variable costs. It represents the portion of sales revenue that is not consumed by variable costs and thus contributes to the coverage of fixed costs and the generation of net profit. It is a vital tool for cost-volume-profit analysis and managerial decision-making.