Chapter 7: Profit Maximization

Vocabulary flashcards covering profit maximization, the MR = MC and P = MC rules, the shutdown condition, and the short-run supply curve in perfectly competitive markets.

Price-Taker

A buyer or seller in a perfectly competitive market who cannot influence the market price through their own actions and must accept the going market price as given.

Profit ($\pi$)

The financial gain obtained after costs are paid, defined mathematically as total revenue minus total cost: $\pi(Q) = TR(Q) - TC(Q)$.

Marginal Revenue ($MR$)

The change in total revenue resulting from selling one additional unit of output.

Marginal Cost ($MC$)

The change in total cost resulting from producing one additional unit of output, defined mathematically as $MC = \frac{dTC}{dQ}$.

$MR = MC$ Rule

The universal profit-maximizing rule that applies to every firm across all market structures, instructing a firm to expand production as long as marginal revenue exceeds marginal cost and stop where the two are equal.

Marginal Revenue for a Price-Taker

The constant marginal revenue faced by a perfectly competitive firm, which is strictly equal to the market price ($MR = P$) because selling an additional unit adds exactly $P \times 1 = P$ to total revenue.

$P = MC$ Rule

The profit-maximizing rule specific to perfectly competitive firms, obtained by substituting $MR = P$ into the general profit-maximizing condition $MR = MC$.

Second-Order Condition for Profit Maximization

The mathematical condition $\frac{d^2\pi}{dQ^2} < 0$, which confirms that the quantity where $P = MC$ corresponds to the peak of profit rather than a local minimum.

Operational Benefit

The revenue generated by keeping a firm open and producing, measured by total revenue ($TR$).

Operational Cost

The extra cost added specifically by producing output, measured by total variable cost ($TVC$).

Total Fixed Cost ($TFC$)

Costs that are sunk or locked in and must be paid in full regardless of whether the firm produces output or shuts down.

Total Variable Cost ($TVC$)

Costs that vary directly with output and drop to zero if the firm chooses to shut down and produce nothing.

Shutdown Rule (Total Terms)

The decision criterion dictating that a firm should operate if operational benefit exceeds operational cost ($TR > TVC$), and shut down if operational benefit is less than operational cost ($TR < TVC$).

Shutdown Rule (Per-Unit Terms)

The per-unit formulation of the shutdown rule: operate where $P = MC$ if $P > AVC$, remain indifferent if $P = AVC$, and shut down (producing $Q = 0$) if $P < AVC$.

Average Variable Cost ($AVC$)

The variable cost incurred per unit of output produced, calculated as $AVC = \frac{TVC}{Q}$.

Average Total Cost ($ATC$)

The total cost incurred per unit of output produced, encompassing both average variable cost and average fixed cost; comparing market price to $ATC$ determines whether a firm earns economic profit or suffers a loss.

Shutdown Point

The point on a firm's cost curves where price equals the minimum average variable cost ($P = \min(AVC)$).

Diminishing Marginal Product

The production principle stating that as additional units of a variable input are added to fixed inputs, each extra unit eventually yields less extra output, causing marginal cost ($MC$) to slope upward.

Firm's Short-Run Supply Curve

The schedule showing output at various prices, defined as zero output when $P < \min(AVC)$ and following the marginal cost ($MC$) curve at and above the minimum of $AVC$.

Loss-Minimizing Operating Condition ($AVC < P < ATC$)

The short-run scenario where market price is below average total cost but above average variable cost, meaning the firm loses money overall but loses less by operating than by shutting down.