In the market for financial capital, the quantity supplied must equal the quantity demanded. Which equation states this as the national saving and investment identity, where S is private saving, I is private investment, G is government spending, T is net taxes, M is imports, and X is exports?
S + (M - X) = I + (G - T)
✓
S + (X - M) = I + (G - T)
S + (M - X) = I + (T - G)
S + (G - T) = I + (M - X)
Correct Answer
S + (M - X) = I + (G - T)
Financial capital is supplied by private saving and by the inflow of foreign saving that matches a trade deficit, M - X, and it is demanded by private investment and by government borrowing to cover the deficit, G - T. S + (X - M) = I + (G - T) uses the trade surplus, which is an outflow, on the supply side. S + (M - X) = I + (T - G) puts public saving where the government's borrowing belongs. S + (G - T) = I + (M - X) swaps the government deficit and the foreign inflow between the two sides.
Category: Saving and Investment Identity
Question 2
In the national saving and investment identity, which term represents the amount the government must borrow to cover its budget deficit?
T - G
G - T
✓
M - X
X - M
Correct Answer
G - T
When government spending G exceeds net taxes T, the difference G - T is the budget deficit the government must borrow. T - G is public saving, which is negative when there is a deficit. M - X is the trade deficit, equal to the inflow of foreign saving. X - M is the trade surplus, which corresponds to an outflow of financial capital.
Category: Saving and Investment Identity
Question 3
A country has private saving of $1,000 billion, net taxes of $600 billion, government spending of $800 billion, imports of $500 billion, and exports of $400 billion. Using I = S + (T - G) + (M - X), what is private investment?
$1,300 billion
$700 billion
$900 billion
✓
$1,100 billion
Correct Answer
$900 billion
I = 1,000 + (600 - 800) + (500 - 400) = 1,000 - 200 + 100 = $900 billion. $1,300 billion treats the $200 billion budget deficit as positive public saving. $700 billion subtracts the $100 billion trade deficit instead of adding it. $1,100 billion makes both sign errors at once, adding the deficit and subtracting the foreign inflow.
Category: Identity Calculations
Question 4
Private investment is $700 billion, private saving is $600 billion, and the government runs a budget deficit of $150 billion. What must the trade deficit be for the financial capital market to balance?
$100 billion
$50 billion
$1,450 billion
$250 billion
✓
Correct Answer
$250 billion
Supply must equal demand: S + (M - X) = I + (G - T), so 600 + (M - X) = 700 + 150, which gives M - X = $250 billion. $100 billion covers only the gap between investment and private saving and ignores the government's borrowing. $50 billion treats the deficit as if it supplied funds. $1,450 billion simply adds all three numbers.
Category: Identity Calculations
Question 5
A government runs a budget surplus of $100 billion. Private investment is $500 billion and the trade deficit is $150 billion. How much private saving does the economy have?
$250 billion
✓
$450 billion
$550 billion
$750 billion
Correct Answer
$250 billion
With a surplus, the government supplies funds, so I = S + (T - G) + (M - X) becomes 500 = S + 100 + 150, and S = $250 billion. $450 billion subtracts the trade deficit but adds the surplus. $550 billion subtracts the surplus but adds the trade deficit. $750 billion adds all three figures together.
Category: Identity Calculations
Question 6
When a government runs a budget surplus, what role does it play in the market for financial capital?
A demander of financial capital
A supplier of financial capital
✓
A source of the trade deficit
A borrower from foreign investors
Correct Answer
A supplier of financial capital
A surplus means net taxes exceed spending, so the government is saving and its funds join private saving on the supply side of the market. A demander of financial capital describes a government running a deficit. A source of the trade deficit confuses public saving with the gap between imports and exports. A borrower from foreign investors also describes a deficit, not a surplus.
Category: Saving and Investment Identity
Question 7
A government's budget deficit rises by $80 billion. If private saving and the trade balance do not change, what must happen according to the national saving and investment identity?
Public saving rises by $80 billion
Private investment rises by $80 billion
Private investment falls by $80 billion
✓
Exports rise by $80 billion
Correct Answer
Private investment falls by $80 billion
With the other sources of funds fixed, every extra dollar the government borrows comes out of financial capital that private firms would have invested, so investment falls by the full $80 billion. Public saving rises by $80 billion is backward, since a larger deficit lowers public saving. Private investment rises by $80 billion reverses the direction of crowding out. Exports rise by $80 billion would change the trade balance, which is held constant.
Category: Crowding Out and Growth
Question 8
A country's budget deficit falls by $50 billion. If private saving and private investment stay the same, what happens to its trade deficit?
It rises by $50 billion
It stays the same
It falls by $100 billion
It falls by $50 billion
✓
Correct Answer
It falls by $50 billion
In S + (M - X) = I + (G - T), a $50 billion drop in G - T with S and I fixed requires M - X to drop by $50 billion, since the country needs that much less foreign financial capital. It rises by $50 billion moves the trade deficit the wrong way. It stays the same would leave the identity out of balance. It falls by $100 billion double counts the change.
Category: Twin Deficits
Question 9
What does the term twin deficits describe?
A budget deficit and a trade deficit at the same time
✓
Budget deficits in two consecutive years
Trade deficits with two major trading partners
Budget deficits at both the federal and state level
Correct Answer
A budget deficit and a trade deficit at the same time
Twin deficits refers to a country running a government budget deficit and a trade deficit together, which the national saving and investment identity links. Budget deficits in two consecutive years is simply a run of deficits. Trade deficits with two major trading partners describes bilateral trade. Budget deficits at both the federal and state level involves no trade at all.
Category: Twin Deficits
Question 10
Foreign investors buy large amounts of U.S. Treasury bonds to help finance a budget deficit, raising the value of the dollar. What is the expected effect on U.S. trade?
Exports rise and imports fall
Exports fall and imports rise
✓
Exports and imports both rise
Exports and imports both fall
Correct Answer
Exports fall and imports rise
A stronger dollar makes U.S. goods more expensive for foreign buyers and foreign goods cheaper for Americans, so exports fall, imports rise, and the trade deficit widens. Exports rise and imports fall is the effect of a weaker dollar. Exports and imports both rise ignores that a price change for foreign buyers moves the two in opposite directions. Exports and imports both fall makes the same mistake in the other direction.
Category: Twin Deficits
Question 11
Which theory holds that rational households increase their private saving to offset higher government borrowing?
Twin deficits hypothesis
Crowding out
Ricardian equivalence
✓
Comparative advantage
Correct Answer
Ricardian equivalence
Ricardian equivalence says households anticipate the future taxes needed to repay government debt and save more today to cover them. The twin deficits hypothesis links budget deficits to trade deficits. Crowding out describes government borrowing reducing private investment. Comparative advantage explains gains from trade and has nothing to do with saving decisions.
Category: Ricardian Equivalence
Question 12
Suppose households fully offset every change in government saving with an equal and opposite change in their own saving. How would private saving respond to a $100 billion increase in the government budget deficit?
It would rise by $30 billion
It would fall by $100 billion
It would stay the same
It would rise by $100 billion
✓
Correct Answer
It would rise by $100 billion
A complete offset, as Ricardian equivalence describes in its strongest form, means private saving changes by an equal and opposite amount to government saving, so a $100 billion larger deficit is matched by $100 billion more private saving, leaving investment and the trade balance unchanged. It would rise by $30 billion describes a partial offset, closer to what U.S. studies find. It would fall by $100 billion moves saving in the wrong direction. It would stay the same describes no offset at all.
Category: Ricardian Equivalence
Question 13
Suppose private saving rises by 30 cents for every $1 of additional government borrowing. If borrowing rises by $200 billion and the trade balance does not change, by how much does private investment fall?
$140 billion
✓
$60 billion
$200 billion
$260 billion
Correct Answer
$140 billion
Private saving rises by 0.30 x $200 billion = $60 billion, so the remaining $200 billion - $60 billion = $140 billion must come out of private investment. $60 billion is the increase in private saving, not the drop in investment. $200 billion assumes no saving response at all. $260 billion adds the saving response instead of subtracting it.
Category: Ricardian Equivalence
Question 14
Under which conditions is crowding out from a larger budget deficit likely to be smallest?
The economy is at potential GDP and the central bank raises interest rates
The economy is well below potential GDP and the central bank holds interest rates low
✓
Private firms want to borrow heavily and the central bank tightens policy
Foreign investors are pulling financial capital out of the country
Correct Answer
The economy is well below potential GDP and the central bank holds interest rates low
When the economy is weak, a central bank is likely to ease policy and keep interest rates low, which limits the rise in rates that discourages private investment. The economy is at potential GDP and the central bank raises interest rates compounds the upward pressure on rates. Private firms want to borrow heavily and the central bank tightens policy also pushes rates higher. Foreign investors are pulling financial capital out of the country reduces the funds available and worsens crowding out.
Category: Crowding Out and Growth
Question 15
Gross private investment equals 16% of GDP, and half of it only replaces worn-out or obsolete capital. If a budget deficit of 2% of GDP came entirely out of private investment, what share of net new investment would be crowded out?
12.5%
50%
25%
✓
2%
Correct Answer
25%
Net new investment is half of 16%, or 8% of GDP, and 2 / 8 = 0.25, so a quarter of it would be crowded out. 12.5% divides the deficit by gross investment, ignoring that half of it only replaces old capital. 50% confuses the replacement share with the crowded-out share. 2% repeats the size of the deficit relative to GDP.
Category: Crowding Out and Growth
Question 16
Between the mid-1990s and 2000, the U.S. federal budget swung from deficit to surplus while private investment rose as a share of GDP. Which idea is this pattern consistent with?
Full Ricardian equivalence
Twin deficits rising together
Higher rates from more borrowing
Less crowding out of investment
✓
Correct Answer
Less crowding out of investment
As the government stopped borrowing and began saving, more financial capital was left for private firms, so investment rose, which fits reduced crowding out. Full Ricardian equivalence would predict that private saving falls one-for-one with the surplus, leaving investment unchanged. Twin deficits rising together describes budget and trade deficits growing at the same time, not a move to surplus. Higher rates from more borrowing would go with larger deficits, not a surplus.
Category: Crowding Out and Growth
Question 17
Head Start is a federal program that represents government investment in which area?
Early childhood education
✓
Highway and bridge construction
Military research
Small business loans
Correct Answer
Early childhood education
Head Start provides early childhood education for families with limited educational and financial resources, a public investment in human capital. Highway and bridge construction is public investment in physical capital. Military research is part of federal research and development spending. Small business loans are a form of credit support, not an education program.
Category: Public Investment
Question 18
Which of the following is an example of government investment in physical capital?
Hiring more public school teachers
Building a new seaport
✓
Paying for job training programs
Funding college scholarships
Correct Answer
Building a new seaport
Physical capital is long-lasting equipment and structures, so a seaport, like roads, bridges, and airports, is public physical capital that can raise private-sector productivity. Hiring more public school teachers is investment in human capital. Paying for job training programs also builds human capital. Funding college scholarships supports education, which is human capital as well.
Category: Public Investment
Question 19
A country runs a government budget deficit and a trade surplus. Which equation correctly describes its market for financial capital?
S + (X - M) = I + (G - T)
S + (G - T) = I + (X - M)
S = I + (G - T) + (X - M)
✓
S = I + (T - G) + (M - X)
Correct Answer
S = I + (G - T) + (X - M)
Private saving is the only source of funds here, and it must cover private investment, government borrowing G - T, and the net outflow of financial capital abroad that matches the trade surplus X - M. S + (X - M) = I + (G - T) wrongly treats the outflow as a source of funds. S + (G - T) = I + (X - M) treats the government's borrowing as a supply of funds. S = I + (T - G) + (M - X) uses public saving and a trade deficit, which are negative numbers in this case.
Category: Saving and Investment Identity
Question 20
Which fiscal policy tool is designed to encourage private firms to spend more on research and development?
Higher taxes on new equipment
Cuts in university research grants
Higher payroll taxes on scientists
Tax credits that grow with research spending
✓
Correct Answer
Tax credits that grow with research spending
An R&D tax credit lowers a firm's taxes as its research spending rises, giving it an incentive to invest in new technology; government also funds research directly through labs and grants. Higher taxes on new equipment would discourage investment. Cuts in university research grants reduce public support for research. Higher payroll taxes on scientists would raise the cost of research work.
Category: Public Investment