- [Instructor] In this video, I want to tackle an entire
AP macroeconomics free response exercise with you.
Assume that the economy of Country X has
an actual unemployment rate of 7%,
a natural rate of unemployment of 5%,
and an inflation rate of 3%.
Using the numerical values given above,
draw a correctly labeled graph of the short-run
and long-run Phillips curves.
Label the current short-run equilibrium as point B.
Plot the numerical values above on the graph.
So pause this video if you are inspired to do so,
but I will now work through it.
So remember, Phillips curves show the relationship
or the theoretical relationship
between the unemployment rate and the inflation rate.
So I'm gonna do the inflation rate
in the vertical axis which is typical.
And then on the horizontal axis,
I am going to do my unemployment rate.
So this is going to be my
unemployment rate
which is going to be a percentage.
Now we want to graph the short-run
and long-run Phillips curves.
Let's do the long-run first because we've seen before
the long-run just sets our unemployment rate
at the natural rate of unemployment,
and it isn't related to our inflation rate.
It'll just be a vertical line.
And so it'll be a vertical line at our natural rate
of unemployment which is 5%.
So maybe it looks just like this.
So I could call that our long-run Phillips curve,
and it's going to be right there at 5%.
And now I have to do the short-run Phillips curve,
and that will show a relationship
between inflation rate and unemployment.
And just think about what's going on.
If you have low rate of unemployment,
especially if it's below your natural rate of unemployment,
well then there's a lot of demand for people.
And so people say, hey, if you want me to work,
you gotta pay me a little bit more,
and so that could just lead to a higher inflation rate.
And then if a lot of people are unemployed,
they might be willing to work for less
or they might have less money in their pocket
with which to drive up the prices, and so you will have
this inverse relationship right over here.
So this is the short-run Phillips curve,
which is downward sloping.
And then they say,
label the short-run equilibrium as point B.
So let's say this is point B right over here.
And they say the short-run equilibrium we have
an unemployment rate of 7% and an inflation rate of 3%.
So our unemployment rate right over here is 7%,
and our inflation rate right over here is 3%.
All right, let's do the next section.
Assume that the government of Country X
takes no policy action to reduce unemployment.
In the long run, which of the following shift to the right,
shift to the left, or remain the same?
So here they're saying short-run
aggregate supply curve, explain.
So here it's kinda tricky 'cause you might be thinking
they're asking about what you just drew.
But here they're talking about aggregate supply.
So let me draw a graph to even help to visualize this.
So if we're talking about aggregate demand
and aggregate supply,
our vertical axis is going to be our price level,
I'll just call that PL,
and our horizontal axis that is going to be our real GDP.
So this is real GDP right over here, G-D-P.
Now you're just going to have a long-run supply curve
which is vertical.
That's just the full employment output for our country.
So that's the long-run aggregate supply.
But what about the short-run aggregate supply curve?
Well, that's going to be upward sloping.
If price levels are low, people might not be willing
to output a lot, and if price levels are high,
people will output more.
So our short-run aggregate supply
would look like that.
I'll call that sub one, since we're gonna think
about how it shifts,
and then aggregate demand would look something like this.
Let me draw it like that.
And notice, our equilibrium point right over here,
let me call that aggregate demand right over here.
Let's call that Y sub one,
and we are at price level sub one.
I drew it to the left
of the long-run aggregate supply curve.
I drew it to the left of the full employment output
because we are dealing with a recession here.
Our unemployment rate is higher
than the natural level of unemployment.
So if our actual unemployment rate is higher
than natural rate of unemployment, what will happen
to the short-run aggregate supply?
So one way to think about it, at a given price level,
because there's people out there looking for a job,
you might be able to get more output.
Or for a given amount of output, it might cost less
because there's just people out there
competing for that work.
And so you would have your short-run aggregate supply curve
shift to the right, short-run aggregate supply sub two.
And then your equilibrium price level would go down,
price level sub two would go down.
So we could say because
of high unemployment,
that could apply wage pressure.
We could say wages come down
which would shift
the short-run aggregate supply curve
to the right.
And there's a couple of ways to think about that.
You would have more output
at a given price level.
You could also think at a given output level,
you would have a lower price level,
at a given price level.
Part two, long-run Phillips curve,
so that's this vertical line right over here.
And the thing to appreciate is the long-run Phillips curve
or the long-run aggregate supply curve,
these don't change unless something structurally changes
in the economy, unless the economy changes
in some very fundamental way,
maybe a change in education levels, change in population,
or change in technology.
And so here we would say it just remains the same.
All right, we have more parts here.
Now let's go to part (c).
Identify a fiscal policy action that could be used
to reduce the unemployment rate in the short run.
So you have to be very careful here.
They're saying a fiscal policy action,
not a monetary policy.
If you said hey, we would change the federal funds rate
or we would increase the money supply
or decrease the money supply,
those would be monetary actions.
We care about a fiscal policy action.
And this would be in relation to lowering taxes
or raising taxes or increasing
or decreasing government spending.
Well, if we want to reduce the unemployment rate,
one way to do the that would be
to shift aggregate demand to the right.
And one way to do that, would be to put more money
in people's pockets,
and one way to do that, is to have a tax cut.
Draw a correctly labeled graph of aggregate demand
and short-run aggregate supply, and show the impact
on the equilibrium price level and real GDP
of the fiscal policy action identified in part (c).
All right, let me draw that.
So this is going to be so that we have
our price level axis up here,
and we just drew something very similar to this, real GDP.
And now let's draw our short-run aggregate supply
which we have seen before.
That would be upward sloping,
as the price level increases or the economy might be willing
to output more, so that's short-run aggregate supply.
And then let's draw an aggregate demand curve.
So let's call that AD sub one.
And then you have the equilibrium output,
let's call that Y sub one.
And you have your equilibrium price level, PL sub one.
And now if you have a tax cut, that would shift
aggregate demand to the right.
At any given price level, people are gonna want more.
They're gonna demand more
'cause now they have more money in their pockets,
and so it's going to shift to the right.
So I'll do a aggregate demand sub two.
And now we have a different equilibrium real GDP,
so that is going to be Y sub two.
And it happens, and then we have price level sub two.
So you see our price level goes up
and our aggregate output, our GDP,
our real GDP, goes up as well.
Based on the change in real GDP identified in part (d),
will the supply of Country X's currency
in the foreign exchange market increase,
decrease, or remain the same, explain?
The way I think about it is if you have real GDP increasing,
you're in a situation where you just have
more economic activity, the national income has gone up.
And if national income has gone up, people are gonna do
a lot more of everything including buying imports.
And to buy imports, they would have to increase the supply
of their currency in exchange markets
because they want to convert it into foreign currencies
to buy those imports, and so this will increase.
And we could say, because national income
has gone up,
people will buy more imports,
so the supply
of Country X's currency
for exchange will go up.
Currency X's currency
for exchange
will go up.
All right, part (f).
Based on your answer to part (e) and assume
a flexible exchange rate system,
will Country X's currency appreciate, depreciate,
or remain the same in the foreign exchange market?
Well, if you hold all else equal,
but you increase the supply of something,
well, then the price of it is going to go down.
If the demand for it stays constant,
but you increase the supply,
and that's what we just talked about in part (e),
well, then the price is going to go down.
And if we're talking about the price of a currency
and we say it's going down, we would say that
that currency is depreciating,
so it would depreciate, and we're done.