Sem 1 Tutorial Flashcards
(55 cards)
how do you calculate gross capital income?
GDP at market price - labour income - (taxes - subsidies)
how do you calculate net capital income?
gross capital income - depreciation
what is net domestic product?
GDP adjusted for depreciation
NDP @ market price = GDP - depreciation rate K
British PPP. The Office for National Statistics reports that GDP per capita in the UK was about £26
000 in 2013, whereas GDP per capita in the United States in 2013 was about $53 000. On a purchasing
power parity (PPP) basis, GDP per capita is listed as about $36 000 in the UK, and $53 000 in the USA.
The average exchange rate in 2013 was about $1.58 per pound.
(a) What is US GDP per capita at market exchange rates (expressed in dollars)? Is this higher or lower
than the PPP measure?
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(b) What is UK GDP per capita at market exchange rates (expressed in dollars)? Is this higher or lower
than the PPP measure?
(c) Based on your answers above, do you think that the price level is higher or lower in the UK? By
how much?
(d) In percentage terms, how much poorer are Brits than Americans when measured at market exchange
rates? What about at PPP? Which measure do you think is better?
This is given in the question: GDPPCUS,$ = $53 000. This is equal to the PPP
measure. The US is the reference country for PPP calculations, so these numbers will always be
equal to one another.
GDPPCUK,$ = GDPPCUK,£ ×ϵ$/£ = 26000 ×1.58 = $41 080 ≈$41 000. This is
higher than the PPP measure.
Prices are higher in the UK. To see how much, take 41 000−36 000
36 000 , which is about
14%. This means that if you took $114 and converted it to £s at market exchange rates, then
the £72 (and change) you would get can buy about as many goods as $100 spent within the
United States.
diff (market rates)= 22.6
diff PPP = 32.07
PPP is generally a better measure for standard-of-living comparisons, because they measure the
real purchasing power of incomes.
Cost minimization. A firm’s production function is given by: Q= K ^1/2 L^1/4 where Q is output in
thousands of units, K is capital input measured in machine-hours and L is labour input measured
in worker-hours. The firm is perfectly competitive and the factor prices are r = £2.50 per hour and
w= £7.50 per hour. The total costs are given by TC= rK+ wL.
Use the method of Lagrange multipliers to find the combination of K and L that minimises the cost of
producing Q= 4.5.
4.5 = (6L)0.5L0.25 ⇐⇒4.5 = 6
1
2 L3
4 = ⇒L=
4.54
62
3
= 2.25; K = 6L= 13.5.
Woodwork. A carpenter plans to make a rectangular wooden box with no lid (that is, open on its top
side) and with a capacity of 108 cubic metres. The necessary wood costs £25 per square metre. Find the
dimensions of the box that will minimize the cost of wood. Find also the minimized cost.
Substitute x= 2z and x= y into (4) to get 108 = 2z·2z·z= 4z3 ⇒z = 3.
Therefore, x = y= 6.
The minimised cost is
TC(x,y,z) = TC(6,6,3) = 50·6·3 + 50·6·3 + 25·6·6 = 2700
Which of the following will affect this year’s UK GDP (and how)? Suppose that a UK owned & operated automotive manufacturer…
…builds a car and sells it to the UK government – this will increase UK GDP
…builds a car and sells it to a Russian – this will increase UK GDP
…builds a car and puts it in inventory to sell next year – this will not affect UK GDP
…imports steel to expand its factory – this will decrease UK GDP
true, true, false, false
Explanation: GDP = C + I + G + X -M. i. adds to G, so is true, ii. adds to X, and so is also true, iii. adds to I, so is false. The only other statement (which students were most likely to be confused about) is iv. – although imports are subtracted from GDP, in this case the steel was also counted in investment. So overall, the steel (being produced abroad) has no effect on UK GDP (but does not reduce it).
Consider the following statements about Gross Domestic Product (GDP) and Gross National Income (GNI). Which (if any) of the statements are true?
|GDP -GNI| = net current transfers from the rest of the world.
For a country where many companies which produce domestically are foreign-owned, we expect GNI > GDP
On average, GNI is about 10% to 15% higher than GDP
Both GDP and GNI are already adjusted for the consumption of capital
FALSE
FALSE
FALSE
FALSE
False - the difference is not net current transfers, but net primary income ii. False (because net primary income will be negative for such a country – e.g. Ireland) iii. False – the average difference should be zero (because worldwide net primary income must add to zero), and a typical gap is just a few percent one way or the other. iv. False – the “gross” in the name of each means that they are not adjusted (the adjusted versions have “net” in the name).
In some country, the capital stock is twice as large as GDP at market price in one year. The depreciation rate is 7%, net exports are negative and equal to minus 5% of GDP, net primary income from the rest of the world is 3% of GDP and net transfers from the rest of the world are 1% of GDP at market price.
Calculate net national disposable income at market price as a percent of GDP at market price.
The first thing to note is that net exports is already in GDP, so we don’t need that number. The first thing we need is to calculate net GDP at market price (net of depreciation). This is 100 − 2 × 0.07 = 86%. To get net national income at market price, we need to adjust this figure for net primary income from the rest of the world, which gives us 86 + 3 = 89%. Finally, to get net national disposable income at market price, we need to add net transfers from the rest of the world, which gives 89 + 1 = 90%
Given the national accounts data below for some country, calculate net national disposable income at market price as a percentage of GDP (rounded to the nearest 1%)
GDP at market price …………………………………… 1000
Deprecation of capital …………………………………. 100
Labour income …………………………………………… 600
Net transfers from abroad ……………………………. -10
Net primary income from abroad …………………… 20
Indirect subsidies (subsidies on products) ………. 30
Indirect taxes (taxes on products) ………………….. 40
As seen in the textbook, the definition of net national disposable income at market price is: GDP + net primary income and net transfers from the rest of the world – consumption of capital. In this case, that’s 1000 + 20 − 10 − 100 = 910 = 91%.
Reusing the data from the previous question, what is gross value added at basic price as a percentage of GDP (rounded to the nearest 1%)
GDP at market price …………………………………… 1000
Deprecation of capital …………………………………. 100
Labour income …………………………………………… 600
Net transfers from abroad ……………………………. -10
Net primary income from abroad …………………… 20
Indirect subsidies (subsidies on products) ………. 30
Indirect taxes (taxes on products) ………………….. 40
As seen in the textbook, the definition of gross value added at basic price is: GDP – taxes less subsidies on products. In this case, that’s 1000 − 40 − 30 = 990 = 99%.
Consider the national income identity. According to the theory developed in the textbook, which of the following must be true in any given year?
C < GDP
G < GDP
X < GDP
M < GDP
Notice that the question emphasised the theory and not the data. In practice, all four of these inequalities are normally true, but in theory any of them can be false. How? The national income identity is: 𝐺𝐷𝑃 = 𝐶 + 𝐼 + 𝐺 + 𝑋 − 𝐼𝑀. Each variable has a value greater than zero, but because imports enter negatively, it means that we can in theory have extreme examples like: 𝐺𝐷𝑃 = 10, 𝐶 = 11, 𝐼 = 11, 𝐺 = 11, 𝑋 = 11, 𝐼𝑀 = 34. A situation like this cannot be sustained for long, but might be true in a given year. For example, during World War II, Malta was a major military outpost for the allies, and imports of military and other equipment were huge relative to domestic production. There are no reliable GDP figures for the time, but it would not be surprising if several of the inequalities above were violated (though not perhaps the one on exports, but as we saw in the tutorial sheet, small trans-shipment states like Singapore can regularly export more than 100% of GDP).
Assume that the real interest rate and the subjective rate of discount are both zero. A person is 20
years old and expects to live to 80 – working for an after-tax salary of £50,000 per year until the age
of 60, then retired with a state pension of £5,000 per year from age 60 until death (and no pension
from work – only whatever savings they have). To simplify, we assume that the person acts as if future
incomes and the length of life were known with certainty. What is his optimal level of consumption and
how much do they save?
From the first order condition u
′ (Ct)
u′ (Ct+1 )= 1+r
1+ρ
we see that if r= ρ, real consumption must
be constant over time, so we have C=
£50k×40+£5k×20
£2100k
=
60
60
= £35k (note: if there is inflation,
it may be that nominal consumption is rising, but we are concerned with real values). Optimal
consumption is thus £35,000 per year in all years – the person will save £15,000 per year while they
work, and dissave £30,000 per year while retired.
A consumer expects to live forever and he/she has a constant labour income of £30,000 per year, no
assets, and a loan of £40,000. The nominal interest rate on the loan is 4% and inflation is 0%.
(a) What is the consumers’ sustainable level of consumption?
Solution: C = 30 000− (0.04− 0.00) × 40000 = 30 000− 1600 = £28 400
Assume that velocity is determined by the function 𝑽 = 𝑽o𝒆𝒃𝒊, where Vo is the ‘base’
velocity, b is a parameter, and t, the nominal interest rate i is determined by 𝒊 = 𝒓𝒏 + 𝝅,
where the natural (real) rate of interest, 𝒓𝒏, is taken as given.
(a) Write down an expression for seignorage as a fraction of GDP. You can assume that
there is no population growth (𝒏 = 𝟎).
b) Calculate an expression for the rate of inflation that maximises seignorage. How
does the result depend on the parameters b and g? Explain the result
S = change in M/PY
but with the things given in the question just sub in
b) inflation = 1/b - g
Suppose that the velocity of the monetary base is 20, real GDP grows 3% per year and
inflation is 2%.
(a) Calculate seignorage relative to GDP
𝛥𝑀/ 𝑃𝑌 = %𝛥 𝑁𝐺𝐷𝑃/ 𝑉
0.03 + 0.02/ 20 = 0.0025 = 0.25% 𝑜𝑓 𝐺𝐷𝑃
Q11. The money supply increases 10% in a year. What is the inflation rate if…
(a) …real production and velocity are constant
(b) …real production grows 4 percent and velocity is constant
(c) …real production is constant and velocity decreases from 2 to 1.8
Using our rule of thumb 𝜋 = 𝛥𝑀 + 𝛥𝑉 − 𝛥𝑌𝑛
, we have 𝜋 = 10% + 0% − 0% = 10%
𝑀 𝑉 𝑌𝑛
b)
𝜋 = 10% + 0% − 4% = 6%
c) Velocity decreases by 10 percent so inflation will be 𝜋 = 10% − 10% − 0% = 0%
Q7.
(a) What is the monetary base?
(b) Is it possible to make purchases without using monetary base?
(c) Is it possible to make loans and pay interest without using monetary base?
(d) Does the central bank have perfect control of the monetary base?
Currency in circulation plus banks’ deposits at the central bank.
Yes. You can barter, for example. Or you can make purchases with the monetary base
(e.g. by using cash).
Yes if you do it in terms of goods and services: I lend you potatoes and you pay back with more potatoes (or with lots of sheep or whatever).
Yes, if the central bank sells a government bond for one million it withdraws one million of monetary base.
Q2. What is the effect on credit markets of each of the following? Make sure to specify
and explain who (if anyone) wins, and who loses.
(a) Unexpected inflation
(b) Unexpected disinflation
c) Expected inflation
d) Expected disinflation
Unexpected inflation will redistribute from lenders to borrowers, since it has the effect
of reducing the value of any payment stream which is fixed in nominal terms (such as a
mortgage, or any other loan).
Many families who took out mortgages with fixed interest rates in the 1960s benefited
from this effect in the 1970s when inflation increased throughout the developed world –
wages and house prices rose with prices, but mortgage payments remained fixed in
nominal terms, hurting banks and helping leveraged homeowners.
Unexpected reductions in inflation (disinflation) have the opposite effect of unexpected
inflation – disinflations redistribute from borrowers to lenders.
Japan in the 1990s and the United States in the 1930s both experienced extended
disinflations (leading to deflation in both cases). Each of these episodes had the effect of
reducing the real wealth of borrowers by increasing the real value of their loan
repayments. Lenders (e.g. banks) correspondingly benefitted from the disinflation
(though both cases were associated with financial crashes, so banks were not doing well
overall).
In general, expected inflation shouldn’t create any winners or losers – financial contracts
will be written taking account of the inflation given the Fisher identity 𝑖 = 𝑟 + 𝜋 for any
target real interest rate r.
One possible caveat is that for governments (such as the UK government) who tax
interest earnings in nominal terms, higher inflation will lead to higher nominal rates and
higher taxes, increasing tax revenues at the expense of participants in the credit market
Like expected inflation, expected disinflation shouldn’t create any winners or losers,
except that the same caveat from above applies in reverse – the tax burden should be
lower in countries where taxes are denoted in nominal terms.
Finding the finding rate. To keep things simple, the textbook model focuses on a situation where
employment and the labour force are constant, and assumes that the employed and the unemployed have
the same probability of finding a job in a given month, and this probability is denoted f. We would like to find the value of f.
(a) The textbook model also makes use of the variables s, Z, N, U, L and u. What are these?
(b) How many job openings are there each month?
(c) How many people are seeking a job?
(d) What is the probability f that a job seeker finds a job in a given month?
(e) How does the value of f that you just found depend on s, u, and Z? Give an intuitive interpretation
for each variable.
s the share of employed workers who apply for other jobs and leave, independently of
whether or not they find another job
Z the share of employed workers who apply for other jobs and quit if they find one
N the number of workers employed
U the number of workers unemployed
L N + U
u U/L
Solution: The number of job openings left by those who leave for exogenous reasons is N · s.
The number of job openings left by those who quit only if they get another job is N · Z · f .
Thus the total number of job openings is N s + N Zf .
Solution: This consists of the workers unemployed at the beginning of the month, U , plus
those who quit exogenously N · s, plus those searching on the job N · Z. Thus, the total number
of people looking for work is given by U + N s + N Z.
Solution:
f = number of openings
number of seekers
f = N s + N Zf
U + N s + N Z
f (U + N s + N Z) = N s + N Zf
U f + N sf + N Zf = N s + N Zf
U f + N sf = N s
f = N s
U + N s
f ≈ s
u + s
Note that the last step uses the approximation L ≈ N . In fact, L = N + U , but since N is
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generally about 15 to 20 times larger than U , the approximation is not too far wrong, and it
simplifies the math quite a bit.
Solution:
∂f
∂s > 0: as the rate of exogenous separation increases, there are more job openings and it is
easier to find a job.
∂f
∂u < 0: as the unemployment rate increases, there are more people seeking work, so the
probability of a given job seeker finding work declines.
∂f
∂Z = 0: the share of employed workers who apply for other jobs and quit if they find one does
not affect the job finding rate; this is because these people create exactly one job opening for
every job they take, and so their effect cancels out.
In contrast to the finding rate which you derived in an earlier question, the finding rate is
sometimes written as f = s/(λu + s). What does λ represent? Who does this finding rate apply to? Give
some intuition for the effect of λ on the job finding rate
Here, λ represents the willingness and ability of the unemployed workers to compete for
jobs. λ is a proportion (i.e., 0 ≤ λ ≤ 1), and so we should think of λU as effective unemployed job
seekers looking for work, rather than the actual number U of job seekers.
When only a proportion λ of the unemployed can search effectively for jobs, f = s/(λu + s) represents
the probability of an employed worker finding a job, whereas the chance of an unemployed worker
finding a job is λf .
When λ decreases, the job finding rate of the employed will rise (because they face less effective
competition), whereas the job finding rate of the unemployed will fall (because they are less effective).
This, in turn, puts upward pressure on wages, so the wage-setting schedule shifts up and the natural
rate of unemployment increases.
Consider the wage setting equation W d/W = 1 + a − bu. What is the effect on wage setting and the natural rate of unemployment of the following shocks:
a) An increase in hiring costs.
(b) A new unemployment agency is created that helps unemployed workers to search more effectively.
(c) A new law limiting the possibilities of unions to call a strike.
Solution: An increase in the hiring cost makes firms more anxious to keep their workers so
they set higher wages; a increases, and the natural rate of unemployment increases.
Solution: If unemployed workers search more effectively, this reduces the chances that employed
workers find other jobs. Firms become less worried about losing their workers so they set lower
wages; a decreases and the natural rate of unemployment decreases.
Solution: If unions become weaker, wages will be lower for a given level of unemployment; a
decreases or b increases, and the natural rate of unemployment decreases.
Efficiency wages and unemployment. The firm’s cost per worker is the direct wage cost plus the
turnover cost per worker:
Wi + h · W ·[s + Z ( Wi/W) · f ]
Where h is the cost of hiring and training a new worker as a fraction of the wage. The firm should (of
course) set wages to minimize this total cost.
(a) When the wage is set so that this cost is minimized, the derivative with respect to the wage is zero. Derive this condition. (Hint: Note that according to the chain rule, the derivative of Z(Wi/W ) with
respect to Wi is Z′ ( Wi/W) /W .
(b) Assume that we are in a symmetric equilibrium where all firms set the same wage. Solve for the
job-finding rate in equilibrium and explain the result.
(c) Set the job finding rate as f = s/(λu + s) and solve for the equilibrium rate of unemployment. What
factors affect unemployment and why?
d) Numerically, what happens to unemployment if λ doubles? Explain intuitively.
(e) Numerically, what happens to unemployment if s becomes twice as high? Explain intuitively.
b) Setting Wi = W we get
1 + hZ′(1)f = 0
Solving for f we get
f = − 1 / hZ′(1)
A few points:
– Z′(·) is negative, because workers at firm i are less likely to look for a new job when Wi/ W is higher.
– f is the proportion of folks finding jobs in a given time period, so 0 < f < 1.
– This implies that |hZ′(1)| > 1, which will be useful later.
– Commenting on the effects of h and Z′(1) on f :
an increase in hiring costs reduces the finding rate.
but note that because Z′(·) is already negative, an increase in Z′(·) means that it becomes closer to zero (from below), so this means that as the negative
slope of the Z function becomes flatter, the finding rate will decrease. Intuitively, as workers become less sensitive to inter-firm wage differentials (Z becomes flatter), they’re less likely to look for other work and so the hiring rate falls
Solution: If λ doubles, unemployment will be halved. (For example, the unemployment rate
will fall from 6 to 3 percent.) If unemployed workers compete twice as well for the jobs, the
unemployment “needed” to prevent wages from rising is reduced.
Solution: If twice as many workers leave their jobs, there will be twice as many job openings
and then we must have twice as many unemployed workers competing for jobs or else there
would be upward pressure on wages.
Shocks to the steady state. Illustrate the effects on the steady state capital stock of the following shocks
and explain the results:
(a) An increase in the depreciation rate
b) An increase in the mark-up.
c) Consumers become more impatient
An increase in the depreciation rate will reduce the net return on investments (given by
f ′(k)/(1 + μ) − δ) for any given level of the capital stock. This is represented by a downward
shift of the net returns curve.
But since the equilibrium value of the net return should still be equal to r, and r has not
changed, something other than the net return must adjust. In this case, the marginal product
of capital – f ′(k) – will increase so as to keep the net return equal to the original value of r.
Given that capital is subject to the law of diminishing returns, the way to get the marginal
product of capital to rise is for the stock of capital to fall, and this is the result of the downward
shift of the net returns curve
The intuition here is very similar to the previous part of the question. When the
mark-up μ rises, then the net return to capital will be lower for any given level of capital, and
this is represented by a downward shift in the net returns curve.
Because the required rate of return r has not changed, a downward adjustment will be made to
the stock of capital.
Intuitively, an increase in the mark-up means that firms set higher prices and invest less so the
steady state capital stock is reduced.
Unlike the previous parts of the question, here we are not changing the net return
for a given level of capital (i.e. we are not shifting the net returns curve), but instead we are
changing the required return r. The required long run return is given by r = ρ + g. If consumers
become more impatient, they require a higher return on lending, and this is represented by
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moving to a higher point on a given net returns curve. Once again, the way to achieve higher
returns in practice is to decrease the stock of capital so as to increase the marginal product of
capital and therefore the gross (and net) returns. Intuitively, greater impatience, reduces the
amount of investment and so the steady state capital stock is reduced