88 
 2) A common supply shock. In each of the regions, let initial unemployment 
be zero, and let initial inflation be zero as well. Step one refers to the common 
supply shock. In terms of the model there is an increase in 
1
B of 3 units, as there 
is in 
1
A . And there is an increase in 
2
B of 3 units, as there is in 
2
A . Step two 
refers to the outside lag. Inflation in Europe goes from zero to 3 percent, as does 
inflation in America. Unemployment in Europe goes from zero to 3 percent, as 
does unemployment in America. 
 
 Step three refers to the policy response. According to the Nash equilibrium 
there is a reduction in European money supply of 4 units and a reduction in 
American money supply of 2 units. Step four refers to the outside lag. Inflation in 
Europe goes from 3 to zero percent. Inflation in America stays at 3 percent. 
Unemployment in Europe goes from 3 to 6 percent. And unemployment in 
America stays at 3 percent. Table 3.16 gives an overview. 
 
 
Table 3.16 
Monetary Interaction between Europe and America 
A Common Supply Shock 
 
 Europe America 
 Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Shock in A
1 
3 
Shock in A
2 
3 
Shock in B
1 
3 
Shock in B
2 
3 
Unemployment 3 Unemployment 3 
Inflation 3 Inflation 3 
Change in Money Supply 
− 4 
Change in Money Supply 
− 2 
Unemployment 6 Unemployment 3 
Inflation 0 Inflation 3    
Monetary Interaction between Europe and America: Case C  
89
 First consider the effects on Europe. As a result, given a common supply 
shock, monetary interaction produces zero inflation in Europe. However, as a 
side effect, it raises unemployment there. Second consider the effects on 
America. As a result, monetary interaction has no effect on inflation and 
unemployment in America. The initial loss of each central bank is zero. The 
common supply shock causes a loss to the European central bank of 9 units and a 
loss to the American central bank of 18 units. Then monetary interaction reduces 
the loss of the European central bank from 9 to zero units. On the other hand, it 
keeps the loss of the American central bank at 18 units.  
 3) A common mixed shock. In each of the regions, let initial unemployment 
be zero, and let initial inflation be zero as well. Step one refers to the common 
mixed shock. In terms of the model there is an increase in 
1
B of 6 units and an 
increase in 
2
B of equally 6 units. Step two refers to the outside lag. Inflation in 
Europe goes from zero to 6 percent, as does inflation in America. Unemployment 
in Europe stays at zero percent, as does unemployment in America.  
 Step three refers to the policy response. According to the Nash equilibrium 
there is a reduction in European money supply of 10 units and a reduction in 
American money supply of 8 units. Step four refers to the outside lag. Inflation in 
Europe goes from 6 to zero percent. Inflation in America goes from 6 to 3 
percent. Unemployment in Europe goes from zero to 6 percent. And 
unemployment in America goes from zero to 3 percent. For a synopsis see Table 
3.17.  
 First consider the effects on Europe. As a result, given a common mixed 
shock, monetary interaction produces zero inflation in Europe. However, as a 
side effect, it produces unemployment there. Second consider the effects on 
America. As a result, monetary interaction lowers inflation in America. On the 
other hand, it raises unemployment there. The initial loss of each central bank is 
zero. The common mixed shock causes a loss to the European central bank of 36 
units and a loss to the American central bank of equally 36 units. Then monetary 
interaction reduces the loss of the European central bank from 36 to zero units. 
Similarly, it reduces the loss of the American central bank from 36 to 18 units. 
2. Some Numerical Examples  
90 
Table 3.17 
Monetary Interaction between Europe and America 
A Common Mixed Shock  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Shock in A
1 
0 
Shock in A
2 
0 
Shock in B
1 
6 
Shock in B
2 
6 
Unemployment 0 Unemployment 0 
Inflation 6 Inflation 6 
Change in Money Supply 
− 10 
Change in Money Supply 
− 8 
Unemployment 6 Unemployment 3 
Inflation 0 Inflation 3    
 4) Another common mixed shock. In each of the regions, let initial 
unemployment be zero, and let initial inflation be zero as well. Step one refers to 
the common mixed shock. In terms of the model there is an increase in 
1
A of 6 
units and an increase in 
2
A of equally 6 units. Step two refers to the outside lag. 
Unemployment in Europe goes from zero to 6 percent, as does unemployment in 
America. Inflation in Europe stays at zero percent, as does inflation in America.  
 Step three refers to the policy response. According to the Nash equilibrium 
there is an increase in European money supply of 2 units and an increase in 
American money supply of 4 units. Step four refers to the outside lag. 
Unemployment in Europe stays at 6 percent. Unemployment in America goes 
from 6 to 3 percent. Inflation in Europe stays at zero percent. And inflation in 
America goes from zero to 3 percent. For an overview see Table 3.18.  
 First consider the effects on Europe. As a result, given another common 
mixed shock, monetary interaction produces zero inflation in Europe. However, 
as a side effect, it produces unemployment there. Second consider the effects on 
Monetary Interaction between Europe and America: Case C  
91
America. As a result, monetary interaction lowers unemployment in America. On 
the other hand, it raises inflation there. The initial loss of each central bank is 
zero. The common mixed shock causes a loss to the European central bank of 
zero units and a loss to the American central bank of 36 units. Then monetary 
interaction keeps the loss of the European central bank at zero units. And what is 
more, it reduces the loss of the American central bank from 36 to 18 units.   
Table 3.18 
Monetary Interaction between Europe and America 
Another Common Mixed Shock  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Shock in A
1 
6 
Shock in A
2 
6 
Shock in B
1 
0 
Shock in B
2 
0 
Unemployment 6 Unemployment 6 
Inflation 0 Inflation 0 
Change in Money Supply 2 Change in Money Supply 4 
Unemployment 6 Unemployment 3 
Inflation 0 Inflation 3    
 5) Summary. Given a common demand shock, monetary interaction produces 
zero inflation and zero unemployment in each of the regions. Given a common 
supply shock, monetary interaction produces zero inflation in Europe. And what 
is more, monetary interaction has no effect on inflation and unemployment in 
America. Given a common mixed shock, monetary interaction produces zero 
inflation in Europe. And what is more, monetary interaction lowers inflation in 
America. On the other hand, it raises unemployment there. 
 2. Some Numerical Examples  
92 
Chapter 4 
Monetary Cooperation 
between Europe and America: Case A    
 The model of unemployment and inflation can be characterized by a system 
of four equations:   
111 2
uAM0.5M=− + (1)  
222 1
uAM0.5M=− + (2)  
11 1 2
B M 0.5Mπ= + − (3)  
22 2 1
BM0.5Mπ= + − (4)  
 As to policy targets there are three distinct cases. In case A the targets of 
monetary cooperation are zero inflation in Europe and America. In case B the 
targets of monetary cooperation are zero inflation and zero unemployment in 
each of the regions. In case C the targets of monetary cooperation are zero 
inflation in Europe, zero inflation in America, and zero unemployment in 
America. This chapter deals with case A, and the next chapters deal with cases B 
and C.  
 The policy makers are the European central bank and the American central 
bank. The targets of monetary cooperation are zero inflation in Europe and 
America. The instruments of monetary cooperation are European money supply 
and American money supply. There are two targets and two instruments. We 
assume that the European central bank and the American central bank agree on a 
common loss function:   
22
12
L =π +π
 (5)  
L is the loss caused by inflation in Europe and America. We assume equal 
weights in the loss function. The specific target of monetary cooperation is to 
minimize the loss, given the inflation functions in Europe and America. Taking  
M. Carlberg, Monetary and Fiscal Strategies in the World Economy, 92
DOI 10.1007/978-3-642-10476-3_12, © Springer-Verlag Berlin Heidelberg 2010  
93
account of equations (3) and (4), the loss function under monetary cooperation 
can be written as follows:   
22
11 2 2 2 1
L (B M 0.5M ) (B M 0.5M )=+− ++−
 (6)  
Then the first-order conditions for a minimum loss are:   
121 2
5M 2B 4B 4M=−+ (7)  
212 1
5M 2B 4B 4M=−+ (8)  
Equation (7) shows the first-order condition with respect to European money 
supply. And equation (8) shows the first-order condition with respect to 
American money supply.  
 The cooperative equilibrium is determined by the first-order conditions for a 
minimum loss. The solution to this problem is as follows:   
112
3M 4B 2B=− − (9)  
221
3M 4B 2B=− − (10)  
Equations (9) and (10) show the cooperative equilibrium of European money 
supply and American money supply. As a result there is a unique cooperative 
equilibrium. An increase in 
1
B causes a reduction in both European and 
American money supply. Obviously, the cooperative equilibrium is identical to 
the corresponding Nash equilibrium. That is to say, monetary cooperation case A 
is equivalent to monetary interaction case A. For some numerical examples see 
Chapter 1.  
Monetary Cooperation between Europe and America: Case A  
94 
Chapter 5 
Monetary Cooperation 
between Europe and America: Case B    
 The model of unemployment and inflation can be represented by a system of 
four equations:   
111 2
uAM0.5M=− + (1)  
222 1
uAM0.5M=− + (2)  
11 1 2
B M 0.5Mπ= + − (3)  
22 2 1
BM0.5Mπ= + − (4)  
 The policy makers are the European central bank and the American central 
bank. The targets of monetary cooperation are zero inflation and zero 
unemployment in each of the regions. The instruments of monetary cooperation 
are European money supply and American money supply. There are four targets 
but only two instruments, so what is needed is a loss function. We assume that 
the European central bank and the American central bank agree on a common 
loss function:   
2222
1212
Luu=π +π + +
 (5)  
L is the loss caused by inflation and unemployment in each of the regions. We 
assume equal weights in the loss function. The specific target of monetary 
cooperation is to minimize the loss, given the inflation functions and the 
unemployment functions. Taking account of equations (1), (2), (3) and (4), the 
loss function under monetary cooperation can be written as follows:   
22
11 2 2 2 1
L (B M 0.5M ) (B M 0.5M )=+− ++− 
22
11 2 22 1
(A M 0.5M ) (A M 0.5M )+−+ + −+
 (6)   
M. Carlberg, Monetary and Fiscal Strategies in the World Economy, 94
DOI 10.1007/978-3-642-10476-3_13, © Springer-Verlag Berlin Heidelberg 2010  
95
Then the first-order conditions for a minimum loss are:   
11212 2
5M 2A A 2B B 4M=−−++ (7)  
221211
5M 2A A 2B B 4M=−−++ (8)  
Equation (7) shows the first-order condition with respect to European money 
supply. And equation (8) shows the first-order condition with respect to 
American money supply.  
 The cooperative equilibrium is determined by the first-order conditions for a 
minimum loss. The solution to this problem is as follows:   
11212
3M 2A A 2B B=+−− (9)  
22121
3M 2A A 2B B=+−− (10)  
Equations (9) and (10) show the cooperative equilibrium of European money 
supply and American money supply. As a result there is a unique cooperative 
equilibrium. An increase in 
1
A causes an increase in both European and 
American money supply. Obviously, the cooperative equilibrium is identical to 
the corresponding Nash equilibrium. That is to say, monetary cooperation case B 
is equivalent to monetary interaction case B. For some numerical examples see 
Chapter 2.  
Monetary Cooperation between Europe and America: Case B  
96 
Chapter 6 
Monetary Cooperation 
between Europe and America: Case C    
 The model of unemployment and inflation can be characterized by a system 
of four equations:   
111 2
uAM0.5M=− + (1)  
222 1
uAM0.5M=− + (2)  
11 1 2
B M 0.5Mπ= + − (3)  
22 2 1
BM0.5Mπ= + − (4)  
 The policy makers are the European central bank and the American central 
bank. The targets of monetary cooperation are zero inflation in Europe, zero 
inflation in America, and zero unemployment in America. The instruments of 
monetary cooperation are European money supply and American money supply. 
There are three targets but only two instruments, so what is needed is a loss 
function. We assume that the European central bank and the American central 
bank agree on a common loss function:   
222
122
L0.50.5u=π + π +
 (5)  
L is the loss caused by inflation in Europe, inflation in America, and 
unemployment in America. We assume equal weights in the loss function. The 
specific target of monetary cooperation is to minimize the loss, given the 
inflation functions and the unemployment function. Taking account of equations 
(2), (3) and (4), the loss function under monetary cooperation can be written as 
follows:  
M. Carlberg, Monetary and Fiscal Strategies in the World Economy, 96
DOI 10.1007/978-3-642-10476-3_14, © Springer-Verlag Berlin Heidelberg 2010  
97
 2
11 2
L(B M 0.5M)=+−  
2
22 1
0.5(B M 0.5M )++−  
2
22 1
0.5(A M 0.5M )+−+
 (6)  
Then the first-order conditions for a minimum loss are:   
12122
5M A 4B B 4M=− − + + (7)  
22121
5M 2A 2B 2B 4M=+−+ (8)  
Equation (7) shows the first-order condition with respect to European money 
supply. And equation (8) shows the first-order condition with respect to 
American money supply.  
 The cooperative equilibrium is determined by the first-order conditions for a 
minimum loss. The solution to this problem is as follows:   
12 12
3M A 4B B=− − (9)  
2212
3M 2A 2B 2B=−− (10)  
Equations (9) and (10) show the cooperative equilibrium of European money 
supply and American money supply. As a result there is a unique cooperative 
equilibrium. Obviously, the cooperative equilibrium is identical to the 
corresponding Nash equilibrium. That is to say, monetary cooperation case C is 
equivalent to monetary interaction case C. For some numerical examples see 
Chapter 3.   
Monetary Cooperation between Europe and America: Case C 
Part Four   
Fiscal Policies 
in Europe and America   
Absence of a Deficit Target   
101
Chapter 1 
Fiscal Interaction 
between Europe and America  
1. The Model    
 The world economy consists of two monetary regions, say Europe and 
America. The monetary regions are the same size and have the same behavioural 
functions. An increase in European government purchases lowers European 
unemployment. On the other hand, it raises European inflation. Correspondingly, 
an increase in American government purchases lowers American unemployment. 
On the other hand, it raises American inflation. An essential point is that fiscal 
policy in Europe has spillover effects on America and vice versa. An increase in 
European government purchases lowers American unemployment and raises 
American inflation. Similarly, an increase in American government purchases 
lowers European unemployment and raises European inflation.  
 The model of unemployment and inflation can be represented by a system of 
four equations:   
111 2
uAG0.5G=−− (1)  
222 1
uAG0.5G=−− (2)  
111 2
BG0.5Gπ= + + (3) 
 222 1
BG0.5Gπ= + + (4)  
 Here 
1
u denotes the rate of unemployment in Europe, 
2
u is the rate of 
unemployment in America, 
1
π is the rate of inflation in Europe, 
2
π is the rate of 
inflation in America, 
1
G is European government purchases, 
2
G is American 
government purchases, 
1
A is some other factors bearing on the rate of 
unemployment in Europe, 
2
A is some other factors bearing on the rate of 
unemployment in America, 
1
B is some other factors bearing on the rate of 
inflation in Europe, and 
2
B is some other factors bearing on the rate of inflation  
M. Carlberg, Monetary and Fiscal Strategies in the World Economy, 101
DOI 10.1007/978-3-642-10476-3_15, © Springer-Verlag Berlin Heidelberg 2010  
102 
in America. The endogenous variables are the rate of unemployment in Europe, 
the rate of unemployment in America, the rate of inflation in Europe, and the rate 
of inflation in America.  
 According to equation (1), European unemployment is a positive function of 
1
A , a negative function of European government purchases, and a negative 
function of American government purchases. According to equation (2), 
American unemployment is a positive function of 
2
A , a negative function of 
American government purchases, and a negative function of European 
government purchases. According to equation (3), European inflation is a 
positive function of 
1
B , a positive function of European government purchases, 
and a positive function of American government purchases. According to 
equation (4), American inflation is a positive function of 
2
B , a positive function 
of American government purchases, and a positive function of European 
government purchases.  
 Now consider the direct effects. According to the model, an increase in 
European government purchases lowers European unemployment. On the other 
hand, it raises European inflation. Correspondingly, an increase in American 
government purchases lowers American unemployment. On the other hand, it 
raises American inflation. Then consider the spillover effects. According to the 
model, an increase in European government purchases lowers American 
unemployment and raises American inflation. Similarly, an increase in American 
government purchases lowers European unemployment and raises European 
inflation.  
 According to the model, a unit increase in European government purchases 
lowers European unemployment by 1 percentage point. On the other hand, it 
raises European inflation by 1 percentage point. And what is more, a unit 
increase in European government purchases lowers American unemployment by 
0.5 percentage points and raises American inflation by 0.5 percentage points. For 
instance, let European unemployment be 2 percent, and let European inflation be 
2 percent as well. Further, let American unemployment be 2 percent, and let 
American inflation be 2 percent as well. Now consider a unit increase in 
European government purchases. Then European unemployment goes from 2 to 
1 percent. On the other hand, European inflation goes from 2 to 3 percent. And 
Fiscal Interaction between Europe and America 
103
what is more, American unemployment goes from 2 to 1.5 percent, and 
American inflation goes from 2 to 2.5 percent.  
 The target of the European government is zero unemployment in Europe. 
The instrument of the European government is European government purchases. 
By equation (1), the reaction function of the European government is:   
112
2G 2A G=− (5)  
Suppose the American government raises American government purchases. 
Then, as a response, the European government lowers European government 
purchases.  
 The target of the American government is zero unemployment in America. 
The instrument of the American government is American government purchases. 
By equation (2), the reaction function of the American government is:   
221
2G 2A G=− (6)  
Suppose the European government raises European government purchases. Then, 
as a response, the American government lowers American government 
purchases.  
 The Nash equilibrium is determined by the reaction functions of the 
European government and the American government. The solution to this 
problem is as follows:   
112
3G 4A 2A=− (7)  
221
3G 4A 2A=− (8)  
Equations (7) and (8) show the Nash equilibrium of European government 
purchases and American government purchases. As a result there is a unique 
Nash equilibrium. According to equations (7) and (8), an increase in 
1
A causes 
an increase in European government purchases and a decline in American 
government purchases. A unit increase in 
1
A causes an increase in European 
government purchases of 1.33 units and a decline in American government 
1. The Model  
104 
purchases of 0.67 units. As a result, given a shock, fiscal interaction produces 
zero unemployment in Europe and America.     
2. Some Numerical Examples    
 For easy reference, the basic model is summarized here:   
111 2
uAG0.5G=−− (1)  
222 1
uAG0.5G=−− (2)  
111 2
BG0.5Gπ= + + (3)  
222 1
BG0.5Gπ= + + (4)  
And the Nash equilibrium can be described by two equations:   
112
3G 4A 2A=− (5)  
221
3G 4A 2A=− (6)  
 It proves useful to study six distinct cases: 
- a demand shock in Europe 
- a supply shock in Europe 
- a mixed shock in Europe 
- another mixed shock in Europe 
- a common demand shock 
- a common supply shock.  
 1) A demand shock in Europe. In each of the regions, let initial 
unemployment be zero, and let initial inflation be zero as well. Step one refers to 
a decline in the demand for European goods. In terms of the model there is an 
increase in 
1
A of 3 units and a decline in 
1
B of equally 3 units. Step two refers 
Fiscal Interaction between Europe and America 
105
to the outside lag. Unemployment in Europe goes from zero to 3 percent. 
Unemployment in America stays at zero percent. Inflation in Europe goes from 
zero to – 3 percent. And inflation in America stays at zero percent.  
 Step three refers to the policy response. According to the Nash equilibrium 
there is an increase in European government purchases of 4 units and a reduction 
in American government purchases of 2 units. Step four refers to the outside lag. 
Unemployment in Europe goes from 3 to zero percent. Unemployment in 
America stays at zero percent. Inflation in Europe goes from – 3 to zero percent. 
And inflation in America stays at zero percent. Table 4.1 presents a synopsis.   
Table 4.1 
Fiscal Interaction between Europe and America 
A Demand Shock in Europe  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Shock in A
1 
3 
Shock in B
1 
− 3  
Unemployment 3 Unemployment 0 
Inflation 
− 3 
Inflation 0 
Change in Govt Purchases 4 Change in Govt Purchases 
− 2 
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0    
 As a result, given a demand shock in Europe, fiscal interaction produces zero 
unemployment and zero inflation in each of the regions. The loss functions of the 
European government and the American government are respectively:  
2. Some Numerical Examples  
106  
2
11
Lu=
 (7)  
2
22
Lu=
 (8)  
The initial loss of the European government is zero, as is the initial loss of the 
American government. The demand shock in Europe causes a loss to the 
European government of 9 units and a loss to the American government of zero 
units. Then fiscal interaction reduces the loss of the European government from 9 
to zero units. And what is more, fiscal interaction keeps the loss of the American 
government at zero units.  
 2) A supply shock in Europe. In each of the regions let initial unemployment 
be zero, and let initial inflation be zero as well. Step one refers to the supply 
shock in Europe. In terms of the model there is an increase in 
1
B of 3 units and 
an increase in 
1
A of equally 3 units. Step two refers to the outside lag. Inflation 
in Europe goes from zero to 3 percent. Inflation in America stays at zero percent. 
Unemployment in Europe goes from zero to 3 percent. And unemployment in 
America stays at zero percent.  
 Step three refers to the policy response. According to the Nash equilibrium 
there is an increase in European government purchases of 4 units and a reduction 
in American government purchases of 2 units. Step four refers to the outside lag. 
Unemployment in Europe goes from 3 to zero percent. Unemployment in 
America stays at zero percent. Inflation in Europe goes from 3 to 6 percent. And 
inflation in America stays at zero percent. Table 4.2 gives an overview.  
 First consider the effects on Europe. As a result, given a supply shock in 
Europe, fiscal interaction produces zero unemployment in Europe. However, as a 
side effect, it raises inflation there. Second consider the effects on America. As a 
result, fiscal interaction produces zero unemployment and zero inflation in 
America. The initial loss of each government is zero. The supply shock in Europe 
causes a loss to the European government of 9 units and a loss to the American 
government of zero units. Then fiscal interaction reduces the loss of the 
European government from 9 to zero units. And what is more, it keeps the loss of 
the American government at zero units.  
Fiscal Interaction between Europe and America 
107
Table 4.2 
Fiscal Interaction between Europe and America 
A Supply Shock in Europe  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Shock in A
1 
3 
Shock in B
1 
3 
Unemployment 3 Unemployment 0 
Inflation 3 Inflation 0 
Change in Govt Purchases 4 Change in Govt Purchases 
− 2 
Unemployment 0 Unemployment 0 
Inflation 6 Inflation 0    
 3) A mixed shock in Europe. In each of the regions, let initial unemployment 
be zero, and let initial inflation be zero as well. Step one refers to the mixed 
shock in Europe. In terms of the model there is an increase in 
1
A of 6 units. Step 
two refers to the outside lag. Unemployment in Europe goes from zero to 6 
percent. Unemployment in America stays at zero percent. Inflation in Europe 
stays at zero percent, as does inflation in America.  
 Step three refers to the policy response. According to the Nash equilibrium 
there is an increase in European government purchases of 8 units and a reduction 
in American government purchases of 4 units. Step four refers to the outside lag. 
Unemployment in Europe goes from 6 to zero percent. Unemployment in 
America stays at zero percent. Inflation in Europe goes from zero to 6 percent. 
And inflation in America stays at zero percent. For a synopsis see Table 4.3.  
 First consider the effects on Europe. As a result, given a mixed shock in 
Europe, fiscal interaction produces zero unemployment in Europe. However, as a 
side effect, it produces inflation there. Second consider the effects on America. 
2. Some Numerical Examples  
108 
As a result, fiscal interaction produces zero unemployment and zero inflation in 
America. The initial loss of each government is zero. The mixed shock in Europe 
causes a loss to the European government of 36 units and a loss to the American 
government of zero units. Then fiscal interaction reduces the loss of the 
European government from 36 to zero units. And what is more, it keeps the loss 
of the American government at zero units.   
Table 4.3 
Fiscal Interaction between Europe and America 
A Mixed Shock in Europe  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Shock in A
1 
6 
Shock in B
1 
0 
Unemployment 6 Unemployment 0 
Inflation 0 Inflation 0 
Change in Govt Purchases 8 Change in Govt Purchases 
− 4 
Unemployment 0 Unemployment 0 
Inflation 6 Inflation 0 
    4) Another mixed shock in Europe. In each of the regions, let initial 
unemployment be zero, and let initial inflation be zero as well. Step one refers to 
the mixed shock in Europe. In terms of the model there is an increase in 
1
B of 6 
units. Step two refers to the outside lag. Inflation in Europe goes from zero to 6 
percent. Inflation in America stays at zero percent. Unemployment in Europe 
stays at zero percent, as does unemployment in America.  
 Step three refers to the policy response. According to the Nash equilibrium 
there is no change in European government purchases, nor is there in American 
Fiscal Interaction between Europe and America 
109
government purchases. Step four refers to the outside lag. Inflation in Europe 
stays at 6 percent. Inflation in America stays at zero percent. Unemployment in 
Europe stays at zero percent, as does unemployment in America. For an 
overview see Table 4.4.  
 First consider the effects on Europe. As a result, given another mixed shock 
in Europe, fiscal interaction produces zero unemployment in Europe. However, 
as a side effect, it produces inflation there. Second consider the effects on 
America. As a result, fiscal interaction produces zero unemployment and zero 
inflation in America. The mixed shock in Europe causes no loss to the European 
government or American government.   
Table 4.4 
Fiscal Interaction between Europe and America 
Another Mixed Shock in Europe  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Shock in A
1 
0 
Shock in B
1 
6 
Unemployment 0 Unemployment 0 
Inflation 6 Inflation 0 
Change in Govt Purchases 0 Change in Govt Purchases 0 
Unemployment 0 Unemployment 0 
Inflation 6 Inflation 0    
 5) A common demand shock. In each of the regions, let initial unemployment 
be zero, and let initial inflation be zero as well. Step one refers to a decline in the 
demand for European and American goods. In terms of the model there is an 
increase in 
1
A of 3 units, a decline in 
1
B of 3 units, an increase in 
2
A of 3 units, 
2. Some Numerical Examples  
110 
and a decline in 
2
B of 3 units. Step two refers to the outside lag. Unemployment 
in Europe goes from zero to 3 percent, as does unemployment in America. 
Inflation in Europe goes from zero to – 3 percent, as does inflation in America.  
 Step three refers to the policy response. According to the Nash equilibrium 
there is an increase in European government purchases and American 
government purchases of 2 units each. Step four refers to the outside lag. 
Unemployment in Europe goes from 3 to zero percent, as does unemployment in 
America. Inflation in Europe goes from – 3 to zero percent, as does inflation in 
America. Table 4.5 presents a synopsis.   
Table 4.5 
Fiscal Interaction between Europe and America 
A Common Demand Shock  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Shock in A
1 
3 
Shock in A
2 
3 
Shock in B
1 
− 3 
Shock in B
2 
− 3 
Unemployment 3 Unemployment 3 
Inflation 
− 3 
Inflation 
 − 3 
Change in Govt Purchases 2 Change in Govt Purchases 2 
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0    
 As a result, given a common demand shock, fiscal interaction produces zero 
unemployment and zero inflation in each of the regions. The initial loss of each 
government is zero. The common demand shock causes a loss to the European 
government of 9 units and a loss to the American government of equally 9 units. 
Then fiscal interaction reduces the loss of the European government from 9 to 
Fiscal Interaction between Europe and America 
111
zero units. Correspondingly, it reduces the loss of the American government 
from 9 to zero units.  
 6) A common supply shock. In each of the regions, let initial unemployment 
be zero, and let initial inflation be zero as well. Step one refers to the common 
supply shock. In terms of the model there is an increase in 
1
B of 3 units, as there 
is in 
1
A . And there is an increase in 
2
B of 3 units, as there is in 
2
A . Step two 
refers to the outside lag. Inflation in Europe goes from zero to 3 percent, as does 
inflation in America. Unemployment in Europe goes from zero to 3 percent, as 
does unemployment in America.  
 Step three refers to the policy response. According to the Nash equilibrium 
there is an increase in European government purchases and American 
government purchases of 2 units each. Step four refers to the outside lag. 
Unemployment in Europe goes from 3 to zero percent, as does unemployment in 
America. Inflation in Europe goes from 3 to 6 percent, as does inflation in 
America. Table 4.6 gives an overview.  
 As a result, given a common supply shock, fiscal interaction produces zero 
unemployment in Europe and America. However, as a side effect, it raises 
inflation there. The initial loss of each government is zero. The common supply 
shock causes a loss to the European government of 9 units and a loss to the 
American government of equally 9 units. Then fiscal interaction reduces the loss 
of the European government from 9 to zero units. Correspondingly, it reduces the 
loss of the American government from 9 to zero units.  
 7) Summary. Given a demand shock in Europe, fiscal interaction produces 
zero unemployment and zero inflation in each of the regions. Given a supply 
shock in Europe, fiscal interaction produces zero unemployment in Europe. 
However, as a side effect, it raises inflation there. Given a mixed shock in 
Europe, fiscal interaction produces zero unemployment in Europe. However, as a 
side effect, it causes inflation there. Given a common demand shock, fiscal 
interaction produces zero unemployment and zero inflation in each of the 
regions. Given a common supply shock, fiscal interaction produces zero 
unemployment in Europe and America. However, as a side effect, it raises 
inflation there.  
2. Some Numerical Examples  
112 
Table 4.6 
Fiscal Interaction between Europe and America 
A Common Supply Shock  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Shock in A
1 
3 
Shock in A
2 
3 
Shock in B
1 
3 
Shock in B
2 
3 
Unemployment 3 Unemployment 3 
Inflation 3 Inflation 3 
Change in Govt Purchases 2 Change in Govt Purchases 2 
Unemployment 0 Unemployment 0 
Inflation 6 Inflation 6   
Fiscal Interaction between Europe and America 
113
Chapter 2 
Fiscal Cooperation 
between Europe and America  
   The model of unemployment and inflation can be characterized by a system 
of four equations:   
111 2
uAG0.5G=−− (1)  
222 1
uAG0.5G=−− (2)  
111 2
BG0.5Gπ= + + (3)  
222 1
BG0.5Gπ= + + (4)  
 The policy makers are the European government and the American 
government. The targets of fiscal cooperation are zero unemployment in Europe 
and America. The instruments of fiscal cooperation are European government 
purchases and American government purchases. There are two targets and two 
instruments. We assume that the European government and the American 
government agree on a common loss function:   
22
12
Lu u=+
 (5) 
 L is the loss caused by unemployment in Europe and America. We assume equal 
weights in the loss function. The specific target of fiscal cooperation is to 
minimize the loss, given the unemployment functions in Europe and America. 
Taking account of equations (1) and (2), the loss function under fiscal 
cooperation can be written as follows:   
22
11 2 2 2 1
L (A G 0.5G ) (A G 0.5G )=−− +−−
 (6)  
Then the first-order conditions for a minimum loss are:   
1122
5G 4A 2A 4G=+− (7)  
M. Carlberg, Monetary and Fiscal Strategies in the World Economy, 113
DOI 10.1007/978-3-642-10476-3_16, © Springer-Verlag Berlin Heidelberg 2010  
114  
2211
5G 4A 2A 4G=+− (8)  
Equation (7) shows the first-order condition with respect to European 
government purchases. And equation (8) shows the first-order condition with 
respect to American government purchases. 
  The cooperative equilibrium is determined by the first-order conditions for a 
minimum loss. The solution to this problem is as follows:   
112
3G 4A 2A=− (9)  
221
3G 4A 2A=− (10)  
Equations (9) and (10) show the cooperative equilibrium of European 
government purchases and American government purchases. As a result there is 
a unique cooperative equilibrium. An increase in 
1
A causes an increase in 
European government purchases and a decline in American government 
purchases. A unit increase in 
1
A causes an increase in European government 
purchases of 1.33 units and a decline in American government purchases of 0.67 
units. Obviously, the cooperative equilibrium is identical to the corresponding 
Nash equilibrium. That is to say, fiscal cooperation is equivalent to fiscal 
interaction. For some numerical examples see Chapter 1.  
Fiscal Cooperation between Europe and America