218 
unemployment functions, and the structural deficit functions. Taking account of 
equations (1) to (6), the loss function under policy cooperation can be written as 
follows: 
 
 
2
11 21 2
2
22 12 1
2
11 21 2
2
22 12 1
22
11 2 2
L(B M 0.5M G 0.5G)
(B M 0.5M G 0.5G )
(A M 0.5M G 0.5G )
(A M 0.5M G 0.5G )
(G T ) (G T )
=+− ++
++− ++
+−+ −−
+−+ −−
+− + −
 (8) 
 
Then the first-order conditions for a minimum loss are: 
 
 112121 2
5M 2A A 2B B 3G 4M=−−+−+ (9)  
2212121
5M 2A A 2B B 3G 4M=−−+−+ (10)  
11212112
7G 2A A 2B B 2T 3M 4G=+−−+−− (11)  
22121221
7G 2A A 2B B 2T 3M 4G=+−−+−− (12)  
Equation (9) shows the first-order condition with respect to European money 
supply. Equation (10) shows the first-order condition with respect to American 
money supply. Equation (11) shows the first-order condition with respect to 
European government purchases. And equation (12) 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. We assume 
12
TT T
=
= . The solution to this problem is as 
follows:   
11212
3M 2A A 2B B 9T=+−−− (13) 
 22121
3M 2A A 2B B 9T=+−−− (14)  
1
GT= (15)  
2
GT= (16)  
Monetary and Fiscal Cooperation between Europe and America 
219
Equations (13) to (16) show the cooperative equilibrium of European money 
supply, American money supply, 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 money supply, an increase in 
American money supply, no change in European government purchases, and no 
change in American government purchases. A unit increase in 
1
A causes an 
increase in European money supply of 0.67 units and an increase in American 
money supply of 0.33 units.  
 As a result, monetary and fiscal cooperation can reduce the loss caused by 
inflation, unemployment, and the structural deficit. Monetary and fiscal 
cooperation is different from monetary and fiscal interaction. This applies to 
cases A, B and C of monetary and fiscal interaction, see Part Seven. On the other 
hand, monetary and fiscal cooperation is equivalent to pure monetary cooperation 
of type B. And what is more, monetary and fiscal cooperation is equivalent to 
pure monetary interaction of type B, see Part Three.  
1. The Model 
220 
2. Some Numerical Examples    
 It proves useful to study eight 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 
-
 a common mixed shock 
-
 another common mixed shock.  
 1) A demand shock in Europe. In each of the regions, let initial 
unemployment be zero, let initial inflation be zero, and let the initial structural 
deficit 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 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. Inflation in America 
stays at zero percent. The structural deficit in Europe stays at zero percent, as 
does the structural deficit in America.  
 Step three refers to the policy response. What is needed, according to the 
model, is an increase in European money supply of 4 units, an increase in 
American money supply of 2 units, no change in European government 
purchases, and no change in American government purchases. 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. Inflation in America stays at zero percent. The structural deficit 
in Europe stays at zero percent, as does the structural deficit in America. For a 
synopsis see Table 7.19.  
 As a result, given a demand shock in Europe, monetary and fiscal 
cooperation produces zero inflation, zero unemployment, and a zero structural 
deficit in each of the regions. The loss function under policy cooperation is: 
Monetary and Fiscal Cooperation between Europe and America 
221 
222222
121212
Luuss=π+π++++
 (1)  
The initial loss is zero. The demand shock in Europe causes a loss of 18 units. 
Then policy cooperation brings the loss down to zero again.   
Table 7.19 
Monetary and Fiscal Cooperation between Europe and America 
A Demand Shock in Europe  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 0 
Shock in A
1 
3 
Shock in B
1 
− 3  
Unemployment 3 Unemployment 0 
Inflation 
− 3 
Inflation 0 
Change in Money Supply 4 Change in Money Supply 2 
Change in Govt Purchases 0 Change in Govt Purchases 0 
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 0    
 2) A supply shock in Europe. In each of the regions let initial unemployment 
be zero, let initial inflation be zero, and let the initial structural deficit 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. 
2. Some Numerical Examples 
222  
 Step three refers to the policy response. What is needed, according to the 
model, is no change in European money supply, no change in American money 
supply, no change in European government purchases, and no change in 
American government purchases. Step four refers to the outside lag. Inflation in 
Europe stays at 3 percent. Inflation in America stays at zero percent. 
Unemployment in Europe stays at 3 percent. Unemployment in America stays at 
zero percent. The structural deficit in Europe stays at zero percent, as does the 
structural deficit in America. For an overview see Table 7.20.  
 As a result, given a supply shock in Europe, monetary and fiscal cooperation 
is ineffective. The initial loss is zero. The supply shock in Europe causes a loss of 
18 units. Then policy cooperation keeps the loss at 18 units.   
Table 7.20 
Monetary and Fiscal Cooperation between Europe and America 
A Supply Shock in Europe  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 0 
Shock in A
1 
3 
Shock in B
1 
3 
Unemployment 3 Unemployment 0 
Inflation 3 Inflation 0 
Change in Money Supply 0 Change in Money Supply 0 
Change in Govt Purchases 0 Change in Govt Purchases 0 
Unemployment 3 Unemployment 0 
Inflation 3 Inflation 0 
Structural Deficit 0 Structural Deficit 0  
Monetary and Fiscal Cooperation between Europe and America 
223
 3) A mixed shock in Europe. In each of the regions, let initial unemployment 
be zero, let initial inflation be zero, and let the initial structural deficit 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. What is needed, according to the 
model, is a reduction in European money supply of 4 units, a reduction in 
American money supply of 2 units, no change in European government 
purchases, and no change in American government purchases. Step four refers to 
the outside lag. Inflation in Europe goes from 6 to 3 percent. Inflation in America 
stays at zero percent. Unemployment in Europe goes from zero to 3 percent. 
Unemployment in America stays at zero percent. The structural deficit in Europe 
stays at zero percent, as does the structural deficit in America. Table 7.21 
presents a synopsis.  
 First consider the effects on Europe. As a result, given a mixed shock in 
Europe, monetary and fiscal cooperation lowers inflation in Europe. On the other 
hand, it raises unemployment there. And what is more, it produces a zero 
structural deficit. Second consider the effects on America. As a result, monetary 
and fiscal cooperation produces zero inflation, zero unemployment, and a zero 
structural deficit in America. The initial loss is zero. The mixed shock in Europe 
causes a loss of 36 units. Then policy cooperation brings the loss down to 18 
units.  
2. Some Numerical Examples 
224 
Table 7.21 
Monetary and Fiscal Cooperation between Europe and America 
A Mixed Shock in Europe  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 0 
Shock in A
1 
0 
Shock in B
1 
6 
Unemployment 0 Unemployment 0 
Inflation 6 Inflation 0 
Change in Money Supply 
− 4 
Change in Money Supply 
− 2 
Change in Govt Purchases 0 Change in Govt Purchases 0 
Unemployment 3 Unemployment 0 
Inflation 3 Inflation 0 
Structural Deficit 0 Structural Deficit 0    
 4) Another mixed shock in Europe. In each of the regions, let initial 
unemployment be zero, let initial inflation be zero, and let the initial structural 
deficit 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. What is needed, according to the 
model, is an increase in European money supply of 4 units, an increase in 
American money supply of 2 units, no change in European government 
purchases, and no change in American government purchases. Step four refers to 
the outside lag. Unemployment in Europe goes from 6 to 3 percent. 
Monetary and Fiscal Cooperation between Europe and America 
225
Unemployment in America stays at zero percent. Inflation in Europe goes from 
zero to 3 percent. Inflation in America stays at zero percent. The structural deficit 
in Europe stays at zero percent, as does the structural deficit in America. Table 
7.22 gives an overview.  
 First consider the effects on Europe. As a result, given another mixed shock 
in Europe, monetary and fiscal cooperation lowers unemployment in Europe. On 
the other hand, it raises inflation there. And what is more, it produces a zero 
structural deficit. Second consider the effects on America. As a result, monetary 
and fiscal cooperation produces zero inflation, zero unemployment, and a zero 
structural deficit in America. The initial loss is zero. The mixed shock in Europe 
causes a loss of 36 units. Then policy cooperation brings the loss down to 18 
units.   
Table 7.22 
Monetary and Fiscal Cooperation between Europe and America 
Another Mixed Shock in Europe  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 0 
Shock in A
1 
6 
Shock in B
1 
0 
Unemployment 6 Unemployment 0 
Inflation 0 Inflation 0 
Change in Money Supply 4 Change in Money Supply 2 
Change in Govt Purchases 0 Change in Govt Purchases 0 
Unemployment 3 Unemployment 0 
Inflation 3 Inflation 0 
Structural Deficit 0 Structural Deficit 0  
2. Some Numerical Examples 
226 
 5) A common demand shock. In each of the regions, let initial unemployment 
be zero, let initial inflation be zero, and let the initial structural deficit 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, 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. What is needed, according to the 
model, is an increase in European money supply of 6 units, an increase in 
American money supply of 6 units, no change in European government 
purchases, and no change in American government purchases. 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. And the structural deficit in Europe stays at zero 
percent, as does the structural deficit in America. For a synopsis see Table 7.23.  
 As a result, given a common demand shock, monetary and fiscal cooperation 
achieves zero inflation, zero unemployment, and a zero structural deficit in each 
of the regions. The initial loss is zero. The common demand shock causes a loss 
of 36 units. Then policy cooperation brings the loss down to zero again.   
Monetary and Fiscal Cooperation between Europe and America 
227
Table 7.23 
Monetary and Fiscal Cooperation between Europe and America 
A Common Demand Shock  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 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 6 Change in Money Supply 6 
Change in Govt Purchases 0 Change in Govt Purchases 0 
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 0    
 6) A common supply shock. In each of the regions, let initial unemployment 
be zero, let initial inflation be zero, and let the initial structural deficit 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. What is needed, according to the 
model, is no change in European money supply, no change in American money 
supply, no change in European government purchases, and no change in 
American government purchases. Step four refers to the outside lag. Inflation in 
Europe stays at 3 percent, as does inflation in America. Unemployment in 
2. Some Numerical Examples 
228 
Europe stays at 3 percent, as does unemployment in America. The structural 
deficit in Europe stays at zero percent, as does the structural deficit in America. 
For an overview see Table 7.24.  
 As a result, given a common supply shock, monetary and fiscal cooperation 
is ineffective. The initial loss is zero. The common supply shock causes a loss of 
36 units. Then policy cooperation keeps the loss at 36 units.   
Table 7.24 
Monetary and Fiscal Cooperation between Europe and America 
A Common Supply Shock  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 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 0 Change in Money Supply 0 
Change in Govt Purchases 0 Change in Govt Purchases 0 
Unemployment 3 Unemployment 3 
Inflation 3 Inflation 3 
Structural Deficit 0 Structural Deficit 0    
 7) A common mixed shock. In each of the regions, let initial unemployment 
be zero, let initial inflation be zero, and let the initial structural deficit 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 
Monetary and Fiscal Cooperation between Europe and America 
229
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. What is needed, according to the 
model, is a reduction in European money supply of 6 units, a reduction in 
American money supply of 6 units, no change in European government 
purchases, and no change in American government purchases. Step four refers to 
the outside lag. Inflation in Europe goes from 6 to 3 percent, as does inflation in 
America. Unemployment in Europe goes from zero to 3 percent, as does 
unemployment in America. The structural deficit in Europe stays at zero percent, 
as does the structural deficit in America. Table 7.25 presents a synopsis.   
Table 7.25 
Monetary and Fiscal Cooperation between Europe and America 
A Common Mixed Shock  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 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 
− 6 
Change in Money Supply 
− 6 
Change in Govt Purchases 0 Change in Govt Purchases 0 
Unemployment 3 Unemployment 3 
Inflation 3 Inflation 3 
Structural Deficit 0 Structural Deficit 0  
 2. Some Numerical Examples 
230 
 As a result, given a common mixed shock, monetary and fiscal cooperation 
lowers inflation. On the other hand, it raises unemployment. And what is more, it 
produces zero structural deficits. The initial loss is zero. The common mixed 
shock causes a loss of 72 units. Then policy cooperation brings the loss down to 
36 units.  
 8) Another common mixed shock. In each of the regions, let initial 
unemployment be zero, let initial inflation be zero, and let the initial structural 
deficit 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. What is needed, according to the 
model, is an increase in European money supply of 6 units, an increase in 
American money supply of 6 units, no change in European government 
purchases, and no change in American government purchases. Step four refers to 
the outside lag. Unemployment in Europe goes from 6 to 3 percent, as does 
unemployment in America. Inflation in Europe goes from zero to 3 percent, as 
does inflation in America. And the structural deficit in Europe stays at zero 
percent, as does the structural deficit in America. Table 7.26 gives an overview. 
  As a result, given another common mixed shock, monetary and fiscal 
cooperation lowers unemployment. On the other hand, it raises inflation. And 
what is more, it produces zero structural deficits. The initial loss is zero. The 
common mixed shock causes a loss of 72 units. Then policy cooperation brings 
the loss down to 36 units.  
Monetary and Fiscal Cooperation between Europe and America 
231
Table 7.26 
Monetary and Fiscal Cooperation between Europe and America 
Another Common Mixed Shock  
 Europe America  
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
Structural Deficit 0 Structural Deficit 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 6 Change in Money Supply 6 
Change in Govt Purchases 0 Change in Govt Purchases 0 
Unemployment 3 Unemployment 3 
Inflation 3 Inflation 3 
Structural Deficit 0 Structural Deficit 0    
 9) Summary. Given a demand shock in Europe, policy cooperation achieves 
zero inflation, zero unemployment, and a zero structural deficit in each of the 
regions. Given a supply shock in Europe, policy cooperation is ineffective. Given 
a mixed shock in Europe, policy cooperation lowers inflation in Europe. On the 
other hand, it raises unemployment there. And what is more, it produces a zero 
structural deficit. Given another type of mixed shock in Europe, policy 
cooperation lowers unemployment in Europe. On the other hand, it raises 
inflation there. And what is more, it produces a zero structural deficit.  
 10) Comparing policy cooperation with other regimes. First, monetary and 
fiscal cooperation is equivalent to pure monetary cooperation of type B, see Part 
Three. Second, monetary and fiscal cooperation is equivalent to pure monetary 
2. Some Numerical Examples 
232 
interaction of type B, see Part Three. Third, monetary and fiscal cooperation is 
superior to monetary and fiscal interaction of type B, see Part Seven. 
Monetary and Fiscal Cooperation between Europe and America 
233
Chapter 5 
Cooperation within Regions, 
Interaction between Regions    
 1) Introduction. The framework of analysis is as follows. There is policy 
cooperation between the European central bank and the European government. 
Similarly, there is policy cooperation between the American central bank and the 
American government. On the other hand, there is policy interaction between 
Europe and America. The targets of policy cooperation within Europe are zero 
inflation, zero unemployment, and a zero structural deficit in Europe. The targets 
of policy cooperation within America are zero inflation, zero unemployment, and 
a zero structural deficit in America.  
 The model of unemployment, inflation, and the structural deficit can be 
represented by a system of six equations:   
111 21 2
uAM0.5MG0.5G=−+ −− (1)  
222 12 1
uAM0.5MG0.5G=− + −− (2)  
11 1 21 2
B M 0.5M G 0.5Gπ= + − + + (3)  
22 2 12 1
B M 0.5M G 0.5Gπ= + − + + (4)  
111
sGT=− (5)  
222
sGT=− (6)  
 2) Policy cooperation within Europe. The policy makers are the European 
within Europe are zero inflation, zero unemployment, and a zero structural deficit 
in Europe. The instruments of policy cooperation within Europe are European 
money supply and European government purchases. 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 European government agree on a common loss 
function:   
M. Carlberg, Monetary and Fiscal Strategies in the World Economy, 233
central bank and the European government. The targets of policy cooperation 
DOI 10.1007/978-3-642-10476-3_25, © Springer-Verlag Berlin Heidelberg 2010  
234  
222
1111
Lus=π + +
 (7)  
1
L is the loss caused by inflation, unemployment, and the structural deficit in 
Europe. We assume equal weights in the loss function. The specific target of 
policy cooperation within Europe is to minimize the loss, given the inflation 
function, the unemployment function, and the structural deficit function. Taking 
account of equations (1), (3) and (5), the loss function under policy cooperation 
within Europe can be written as follows:   
2
111 21 2
2
11 21 2
2
11
L(BM0.5MG0.5G)
(A M 0.5M G 0.5G )
(G T )
=+− ++
+−+ −−
+−  
Then the first-order conditions for a minimum loss are:   
111 12 2
2M A B 2G G M=−− −+ (9) 
 1111 1 22
3G A B T 2M M G=−+− + − (10)  
Equation (9) shows the first-order condition with respect to European money 
supply. And equation (10) shows the first-order condition with respect to 
European government purchases.  
 The cooperative equilibrium in Europe is determined by the first-order 
conditions for a minimum loss. The solution to this problem is as follows:   
111 12 2
2M A B 2T G M=−− −+ (11)  
11
GT= (12)  
Equations (11) and (12) show the cooperative equilibrium of European money 
supply and European government purchases. Equation (11) is the reaction 
function of the European central bank. And equation (12) is the reaction function 
of the European government.  
 3) Policy cooperation within America. The policy makers are the American 
central bank and the American government. The targets of policy cooperation 
(8) 
Cooperation within Regions, Interaction between Regions  
235
within America are zero inflation, zero unemployment, and a zero structural 
deficit in America. The instruments of policy cooperation within America are 
American money supply and American government purchases. There are three 
targets but only two instruments, so what is needed is a loss function. We assume 
that the American central bank and the American government agree on a 
common loss function:   
222
2222
Lus=π + +
 (13)  
2
L is the loss caused by inflation, unemployment, and the structural deficit in 
America. We assume equal weights in the loss function. The specific target of 
policy cooperation within America is to minimize the loss, given the inflation 
function, the unemployment function, and the structural deficit function. Taking 
account of equations (2), (4) and (6), the loss function under policy cooperation 
within America can be written as follows:   
2
222 12 1
2
22 12 1
2
22
L(BM0.5MG0.5G)
(A M 0.5M G 0.5G )
(G T )
=+− ++
+−+ −−
+−  
Then the first-order conditions for a minimum loss are:   
222 211
2M A B 2G G M=−− −+ (15)  
2222 211
3G A B T 2M M G=−+− +− (16)  
Equation (15) shows the first-order condition with respect to American money 
supply. And equation (16) shows the first-order condition with respect to 
American government purchases.  
 The cooperative equilibrium in America is determined by the first-order 
conditions for a minimum loss. The solution to this problem is as follows:   
222 211
2M A B 2T G M=−− −+ (17)  
22
GT= (18)  
(14) 
Cooperation within Regions, Interaction between Regions 
 236 
Equations (17) and (18) show the cooperative equilibrium of American money 
supply and American government purchases. Equation (17) is the reaction 
function of the American central bank. And equation (18) is the reaction function 
of the American government.  
 4) Policy interaction between Europe and America. The Nash equilibrium is 
determined by the reaction functions of the European central bank, the American 
central bank, the European government, and the American government. We 
assume 
12
TT T==. The solution to this problem is as follows:   
11212
3M 2A A 2B B 9T=+−−− (19)  
22121
3M 2A A 2B B 9T=+−−− (20)  
1
GT= (21)  
2
GT= (22)  
Equations (19) to (22) show the Nash equilibrium of European money supply, 
American money supply, European government purchases, and American 
government purchases. As a result there is a unique Nash equilibrium. An 
increase in 
1
A causes an increase in European money supply, an increase in 
American money supply, no change in European government purchases, and no 
change in American government purchases.  
 5) Comparing the system of cooperation and interaction with other types of 
systems. First, the system of cooperation and interaction is equivalent to the 
system of monetary and fiscal cooperation, see Part Seven. Second, the system of 
cooperation and interaction is equivalent to the system of monetary cooperation 
B, see Part Three. Third, the system of cooperation and interaction is equivalent 
to the system of monetary interaction B, see Part Three. 
Cooperation within Regions, Interaction between Regions  
238 
Synopsis   
Table 8.1 
Monetary Policies in Europe and America   
Monetary Interaction 
between Europe and America 
Unique 
Nash Equilibrium  
Monetary Cooperation 
between Europe and America  
Unique 
Solution  
Cooperative Solution 
Is Identical to 
Nash Equilibrium       
Table 8.2 
Fiscal Policies in Europe and America 
Presence of a Deficit Target   
Fiscal Interaction 
between Europe and America 
Unique 
Nash Equilibrium  
Fiscal Cooperation 
between Europe and America  
Generally, 
Cooperative Solution 
Is Different from 
Nash Equilibrium  
Unique 
Solution   
238 
239
Table 8.3 
Monetary and Fiscal Policies in Europe and America 
Absence of a Deficit Target   
Monetary and Fiscal Interaction 
between Europe and America 
No 
Nash Equilibrium  
Monetary and Fiscal Cooperation 
between Europe and America  
Multiple 
Solutions      
Table 8.4 
Monetary and Fiscal Policies in Europe and America 
Presence of a Deficit Target 
  Monetary and Fiscal Interaction 
between Europe and America 
Unique 
Nash Equilibrium  
Monetary and Fiscal Cooperation 
between Europe and America  
Generally, 
Cooperative Solution 
Is Different from 
Nash Equilibrium  
Unique 
Solution   
Synopsis   
241
Conclusion  
1. Monetary Policies in Europe and America  
1.1. Monetary Interaction between Europe and America: 
 Case A  
   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 money supply lowers European 
unemployment. On the other hand, it raises European inflation. Correspondingly, 
an increase in American money supply lowers American unemployment. On the 
other hand, it raises American inflation. An essential point is that monetary 
policy in Europe has spillover effects on America and vice versa. An increase in 
European money supply raises American unemployment and lowers American 
inflation. Similarly, an increase in American money supply raises European 
unemployment and lowers European inflation.  
 In the numerical example, a unit increase in European money supply 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 money supply raises American unemployment by 0.5 percentage 
points and lowers 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 money 
supply. Then European unemployment goes from 2 to 1 percent. On the other 
hand, European inflation goes from 2 to 3 percent. And what is more, American 
unemployment goes from 2 to 2.5 percent, and American inflation goes from 2 to 
1.5 percent.  
 The target of the European central bank is zero inflation in Europe. The 
instrument of the European central bank is European money supply. From this 
follows the reaction function of the European central bank. Suppose the  
241  
242 
American central bank lowers American money supply. Then, as a response, the 
European central bank lowers European money supply. The target of the 
American central bank is zero inflation in America. The instrument of the 
American central bank is American money supply. From this follows the reaction 
function of the American central bank. Suppose the European central bank 
lowers European money supply. Then, as a response, the American central bank 
lowers American money supply.  
 The Nash equilibrium is determined by the reaction functions of the 
European central bank and the American central bank. It yields the equilibrium 
levels of European money supply and American money supply. As a result, given 
a shock, monetary interaction produces zero inflation in Europe and America.  
 2) A demand shock in Europe. Let initial unemployment in Europe be 3 
percent, and let initial unemployment in America be zero percent. Let initial 
inflation in Europe be – 3 percent, and let initial inflation in America be zero 
percent. Step one refers to the policy response. According to the Nash 
equilibrium there is an increase in European money supply of 4 units and an 
increase in American money supply of 2 units. Step two 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 9.1 presents a synopsis. As 
a result, given a demand shock in Europe, monetary interaction produces zero 
inflation and zero unemployment in each of the regions.  
 3) A supply shock in Europe. Let initial inflation in Europe be 3 percent, and 
let initial inflation in America be zero percent. Let initial unemployment in 
Europe be 3 percent, and let initial unemployment in America be zero percent. 
Step one 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 two refers to the outside lag. Inflation in Europe 
goes from 3 to zero percent. Inflation in America stays at zero percent. 
Unemployment in Europe goes from 3 to 6 percent. And unemployment in 
America stays at zero percent. Table 9.2 gives an overview. First consider the 
effects on Europe. As a result, given a supply shock in Europe, monetary 
interaction produces zero inflation in Europe. However, as a side effect, it raises 
Conclusion 
243
unemployment there. Second consider the effects on America. As a result, 
monetary interaction produces zero inflation and zero unemployment in America.   
Table 9.1 
Monetary Interaction between Europe and America 
A Demand Shock in Europe  
 Europe America  
Unemployment 3 Unemployment 0 
Inflation 
− 3 
Inflation 0 
Change in Money Supply 4 Change in Money Supply 2 
Unemployment 0 Unemployment 0 
Inflation 0 Inflation 0 
   Table 9.2 
Monetary Interaction between Europe and America 
A Supply Shock in Europe  
 Europe America  
Unemployment 3 Unemployment 0 
Inflation 3 Inflation 0 
Change in Money Supply 
− 4 
Change in Money Supply 
− 2 
Unemployment 6 Unemployment 0 
Inflation 0 Inflation 0      
1. Monetary Policies in Europe and America   
244 
1.2. Monetary Interaction between Europe and America: 
 Case B   
  1) The model. The targets of the European central bank are zero inflation and 
zero unemployment in Europe. The instrument of the European central bank is 
European money supply. There are two targets but only one instrument, so what 
is needed is a loss function. We assume that the European central bank has a 
quadratic loss function. The amount of loss depends on inflation and 
unemployment in Europe. The European central bank sets European money 
supply so as to minimize its loss. From this follows the reaction function of the 
European central bank.  
 The targets of the American central bank are zero inflation and zero 
unemployment in America. The instrument of the American central bank is 
American money supply. There are two targets but only one instrument, so what 
is needed is a loss function. We assume that the American central bank has a 
quadratic loss function. The amount of loss depends on inflation and 
unemployment in America. The American central bank sets American money 
supply so as to minimize its loss. From this follows the reaction function of the 
American central bank.  
 The Nash equilibrium is determined by the reaction functions of the European 
central bank and the American central bank. It yields the equilibrium levels of 
European money supply and American money supply. As a rule, inflation in 
Europe and America is not zero. And unemployment in Europe and America is 
not zero either.  
 2) A demand shock in Europe. We assume equal weights in each of the loss 
functions. Let initial unemployment in Europe be 3 percent, and let initial 
unemployment in America be zero percent. Let initial inflation in Europe be – 3 
percent, and let initial inflation in America be zero percent. Step one refers to the 
policy response. According to the Nash equilibrium there is an increase in 
European money supply of 4 units and an increase in American money supply of 
2 units. Step two refers to the outside lag. Unemployment in Europe goes from 3 
to zero percent. Unemployment in America stays at zero percent. Inflation in 
Conclusion