Managerial economics 3rd by froeb ch04

Chapter 4 – Summary cont.• Marginal revenue MR is the additional revenue gained from selling one more unit.. • The relevant costs and benefits of an extent decision are marginal costs

Chapter 4 Extent (How Much)

Decisions

Chapter 4 – Summary of main

points

• Do not confuse average and marginal

costs.

• Average cost (AC) is total cost (fixed and

variable) divided by total units produced.

• Average cost is irrelevant to an extent

decision.

• Marginal cost (MC) is the additional cost

incurred by producing and selling one more unit.

Chapter 4 – Summary (cont.)

• Marginal revenue (MR) is the additional

revenue gained from selling one more unit.

• Sell more if MR > MC; sell less if MR < MC If MR =

MC, you are selling the right amount (maximizing profit).

• The relevant costs and benefits of an extent

decision are marginal costs and marginal revenue If the marginal revenue of an activity is larger than the marginal cost, then do more of it.

• An incentive compensation scheme that increases marginal revenue or reduces marginal cost will

increase effort Fixed fees have no effects on effort.

• A good incentive compensation scheme links pay

to performance measures that reflect effort.

Introductory anecdote: US Financial

Crisis

• The financial crisis began in the subprime

housing market, where government policies encouraged lenders to extend credit to

low-income borrowers (by lowering lending

standards)

• Concurrently mortgages were being packaged into securities and sold to investors.

• If the risk had been recognized investor

demand would have been low, but rating

agencies were too liberal with AAA ratings,

increasing demand for loans.

• The result? A credit “bubble”

• How did this lending crisis arise?

Background: Average cost

• Definition: Average cost is simply the total

cost of production divided by the number of units produced AC = TC/Q

• Average costs often decrease as quantity increases due to presence of fixed costs

• AC = (VC + FC)/Q

• FC does not change as Q increases

• Average costs are not relevant to extent

decisions

Background: Average cost

(cont.)

Background: Marginal cost

• Marginal cost is the cost to make

and sell one additional unit of output

MC = TC Q+1 – TC Q

• Marginal cost is often lower than

average cost (due to falling average costs) but not always.

• Marginal costs are what matter in

extent decisions

Extent (how much?)

decisions

• Definition: Marginal cost (MC) is the

additional cost required to produce and sell one more unit

• Definition: Marginal revenue (MR) is

the additional revenue gained from producing and selling one more unit

• If the benefits of selling another unit (MR) are bigger than the costs (MC), then sell another unit.

when MR<MC Profits are maximized when MR=MC

Extent decisions (cont.)

• Examples of extent decisions

• Should you change the level of advertising?

• Should you increase the quality of service?

• Is your staff big enough, or too big?

• How many parking spaces should you lease?

• Marginal analysis answers these questions

• This analysis tells you direction of change but not the distance

• You can only measure MR and MC at the current level of output – make a change and re-measure

Extent decision example

• Discussion: How much advertising?

• A $50,000 increase in the TV ad budget brings in 1,000 new customers

• Estimated MC TV is $50 (the cost to get one more

customer)

• $50,000 / 1,000 = $50

• If the marginal revenue generated by this customer

is greater than $50, do more advertising.

Extent decision example

(cont.)

• Even if we do not know the marginal revenue, we can still use marginal analysis to make extent decisions

• Compare TV advertising to telephone solicitation

• Say you recently cut telephone budget by $10,000 and lost 100 customers

• Estimated MC PH = $100= ($10,000 / 100)

• So, to get one more customer costs $50 for TV and $100 for phone

• MC PH > MC TV so shift ad dollars from phone to TV

• Advice: make changes one-at-a-time to gather

valuable information about marginal effectiveness of each medium.

Another example

• SAH=“Standard Absorbed Hours” a measure of

textile factory output

• Allows managers to compare factories making different items, e.g t-shirt = 1 SAH while dress=3 SAH

• Suppose Factory A has costs of $30 per SAH while Factory B has cost of $20 per SAH How can you profitably use this information?

• The decision seems simple, but

• Make sure you are not including fixed costs in the analysis

• Marginal costs matter, not average costs!

• If the $20 and $30 rates are good MC proxies, shift some production from Factory A to Factory B

Effort is an extent decision

• Discussion: Royalty rates vs fixed fee contracts

• You receive two bids to harvest 100 trees on your land

• $150/tree or $15,000 for the right to harvest all the trees.

• On your tract there are pines (worth $200) and fir (worth $100)

• Which offer should you accept?

• Discussion: Sales Commissions

• Expected sales level: 100 units @ $10,000/unit=$1M

• Option 1: 10% commission

• Option 2: 5% commission + $50,000 salary

rate or fixed fee contracts in your firm

Tie pay to performance

• A consulting firm COO received a flat salary of

$75,000

• After learning about the benefits of incentive pay

in class, the CEO changed COO compensation to

$50K + (1/3)* (Profits-$150K)

• Profits increased 74% to $1.2 M

• Compensation increased $75K  $177K

• Discussion: what are the disadvantages to

incentive pay?

Alternate intro anecdote

• American Express offers a Platinum Card to affluent customers

• In 2001, there were approximately 2,000 Platinum cardholders in the Japanese market Numbers had been limited to ensure high quality customer service

• With customer service technology advances, company considered expanding number of card holders

• How many more should be added?

decreases because the financial threshold for membership is lowered

growing beyond a certain point would require building and operating

an additional call center

it should expand its offering to only 15,000 more Platinum Card members

• We call this an “extent” decision, because the company needed to