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Course: Microeconomics > Unit 8
Lesson 3: Optimal choice of factors in perfectly competitive factor marketsFactor markets worked example
In this video, learn how to apply the analysis of factor markets to a sample problem.
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- If Epic Eats operates in a perfectly competitive market and its price increases doesn't that mean that the price of every other firm in the stuffed sand which market increases. And if their prices are increasing, shouldn't the market demand for labour increase thus leading to an increase in wage rate?(7 votes)
- But if the price of stuffed sandwiches goes up, won't the quantity demanded go down?
I'd have thought the result would be literally the opposite of the result you showed, as the decrease in quantity demanded would drive revenue down and make it more desirable to hire fewer workers and pay them less.
Too much left up to assumption I guess.(4 votes)- The supply and demand plotted in the video are of labour and not sandwiches.(3 votes)
- Question b.ii, time signature ~5:20:
The term "short run" may create too much uncertainty to answer confidently, other than "underterminable." Isn't the definition of "short run" a time period so short that at least one factor of production is fixed?
My first reaction-answer was the one Sal provided, but being careful with how key economic terms change the parameters of the question (perfectly competitive, short/long run, etc), it seemed Epic Eats actually might not hire anyone due to the very concept of "short run" as it relates to factors of production. In short run, we know at least one factor of production is fixed or hard to change quickly. We do not know if labor is one of those easily changed or more fixed..
The best answer might be: "unknown in short run, will hire more in long run."
Is there a better way to understand that term on exams? (preparing for CLEP Micro)
Y'all rock! Thank you! Metairie v Algiers throwdown! 70131 ya heard!(2 votes)- I'm here late but short-run is defined as the period it takes for the most fixed input to change. So in an example of a bakery the inputs are Labour (takes a day to fire and hire someone), Wheat (takes a week to change the delivery) and the Ovens (takes 6 months to install or sell ovens), In this example 6 months is the short run since that's the time it takes to change the most fixed input (ovens).
In general theory Labour is always harder to change than Capital. So in this example the firm either has no Capital, meaning that Labour is the most fixed input and therefore Labour should be able to change in the short-run, or the firm has Capital and then Labour can also be changed in the short-run.(2 votes)
- Hello. Could you please tell me where you get these questions?(2 votes)
- Sometimes they are in your practice lessons if you keep restarting the lession you might get the questions that you want. Edit: it helps you when you need to pass but I suggest you write down the question then the answer so you don't have to restart so many times(1 vote)
- Why does the wage for firm remain same after the demand has increased(1 vote)
- it's a perfectly competitive labor market, so the firm is a price-taker for wage. the firm has no market power over the wage and cannot affect it(1 vote)
- if D=MRP, how does an increase in price shift the curve to the right? b.ii(1 vote)
Video transcript
- [Narrator] We're told that Epic Eats is a perfectly competitive,
profit-maximizing producer of stuffed sandwiches, and hires workers in a perfectly competitive labor market. Part A says, draw side-by-side
graphs for the labor market and for Epic Eats and show
each of the following. So pause this video and see
if you could have a go at it before we do it together. All right, now let's do it together. So we're gonna do side-by-side graphs, one for the market, and
one for the firm Epic Eats. So let me do that. So, this will be my market. This is my market graph. And so this is going to
be quantity of labor. Quantity of labor. And then on the vertical
axis, I have my wages, which you could view as the
price of labor, the wage rate. And so this is the market. And then over here, I
wanted it side-by-side. This is going to be the firm. This is going to be Epic Eats. Once again, I have
quantity, quantity of labor. And I'm going to have the wage rate. And this is Epic Eats. That's the firm level. Now, they want us to show the market wage and the quantity of workers
hired in the market. Well, to do that, we're
going to have to think about the demand for workers in the market. Well, at a high wage
rate, there's not gonna be a lot of labor demanded. And then as the wage goes
down, more, more people are going to wanna hire people. This is the market labor demand curve. Demand curve. And then then supply curve
is gonna be upward sloping. At a low wage rate, not a lot
of people are going to wanna give their labor. But then as wages go up, people will, more and more people are likely do enter, want to be part of the labor force. So this is going to be the
market labor supply curve. And then we have our equilibrium wage, which they want us to label W sub M. So that is going to be right over here. W, sub lowercase M. And then the quantity of
workers hired in the market is going to be capital L, sub lowercase M. Capital L, sub lowercase M. So we did this first part, the fact part that focuses on the market. Then they want us to focus on
the marginal factor cost curve labeled MFC. Well that's what it's
going to cost Epic Eats to hire folks. And we're dealing with a, it hires in a perfectly
competitive labor market. So which is gonna pay the market wages. So let me do that. So this is going to be the
price it pays for labor which is its marginal factor cost curve, MFC, just like that. So I did the second part. The marginal revenue product, labeled MRP. Well the way you typically look at it, it is for Epic Eats that it has some marginal revenue product
at a certain quantity. And then as it hires more and more people, intends to have diminishing returns. So typical marginal revenue product curve looks something like this. So it's MRP, did that part. The wage paid by the
firm, labeled W sub F, and the quantity of
workers hired by the firm, labeled L sub F. Well the wage paid by the firm, that's dictated by the market wage. So we can say that this is
equal to the market wage, which is equal to the
wage paid by the firm. And you could put this over here. The wage paid by the
firm is right over there. So I did this first part, and the quantity of
workers hired by the firm. Well what would be rational is, is that they would keep hiring people until the marginal revenue
product is no longer higher than that marginal cost of
hiring that extra unit of labor. So it's right at that
point of intersection. And so that is the quantity
of workers hired by the firm, so L. Now let's do the next part. It says, assume that there is an increase in the price of Epic
Eats' stuffed sandwiches. In the short run, will
the wage paid by Epic Eats be higher than, lower
than, or equal to W, sub F? Explain. So pause this video and
see if you can answer that. Well in the short run, Epic Eats, no matter how much it
hires or doesn't hire, it's just going to pay the same wage. So we could say, it is
going to be equal to. Equal, equal. So pay equal to WF because operating in perfectly competitive labor market. Labor market. In the short run, what will
happen to the number of workers hired by Epic Eats? Explain. So in the short run, if
the wage is being the same, but hey had a price increase. So that means that the MRP is
going to shift to the right because per unit, they're
going to be able to sell it for more, you're gonna a have a situation where the MRP switches
shifts to the right, or right and up. And so you're gonna have MRP to, this is after the price increase. And notice, now we intersect
the MFC line at a higher point. And so what will happen to
the number of workers hired? So number of workers goes up because MRP shifts up due to price increase which causes it to intersect your marginal factor
cost curve, MFC at higher quantity of labor hired. All right, now let's do part C. Epic Eats uses capital and labor in the production of sandwiches. The marginal product of the
last unit of capital used is 4,000 units and the marginal
product of the last unit of labor used is 3,000. If Epic Eats minimizes costs
and the rental rate of capital is $400, what is the wage rate? So pause this video and see
if you could answer that. All right, so they give us a few things. So the marginal product of
the last unit of capital. So you say, marginal product
of the last unit of capital. I used K for capital even
though I know it's... Not to confuse ourselves
with something else. Although, you could argue
to use C, but we'll use K to ease confusion. So the marginal product
of the unit of capital is equal to 4,000 units. We know that the marginal
product of the last unit of labor is equal to 3,000 units. And we could view this right of here. The rental rate of
capital, you can view this as the price of capital. You could also view this
as the marginal factor cost of capital, but I'll just call this the price of capital is equal to $400. And they want us to get the wage rate.. So you could view this
as the price of labor is equal to what? And they tell us that
it's minimizing cost. And what we can think about
it is, the number of units per dollar that the firm
gets it on the margin, if they're able to get
more units per dollar by switching, by putting
that extra dollar into labor versus capital, or capital versus labor, they're going to do it. So what we would assume is,
is that the number of units per dollar that they're
getting at this point are going to be the
same whether they invest in labor or capital. And so the number of units per
dollar that they're getting from the capital is the
marginal product of the capital divided by the price of the capital this is the number of units per dollar. And this needs to be equal to
the number of units per dollar that they're getting from
that last unit of labor. So that's the marginal product of labor. So the units they're getting
from labor on the margin divided by the price
of labor on the margin, and then we just solve for this. So this will get us to,
we're gonna have 4,000, this is 4,000 units divided by $400. It's going to be equal
to 3,000 units divided by the price of labor. So you can manipulate this a little bit, you could divide both sides by 400. So this is going to be
10 units per dollar. So let me scroll down a
little bit right over here. So we could, this is, let's see... Yup, this is going to
be 10 units per dollar is going to be equal to
3,000 units divided by the price of labor. And so, you just do a
little bit of manipulation, multiply both sides by the price of labor, divide both sides by 10. You do a little bit of Algebra. This gets you to $300 per, for the incremental cost of labor. So this is going to get
us to the price of labor is equal to $300. And you can verify that,
you could plug it back in if you like. And we're done!