112
MATHEMATICAL APPENDIX to Optimal continuous cover forest management: - Economic and environmental effects and legal considerations Professor Dr Peter Lohmander http://www.Lohmander.com [email protected] BIT's 5 th Low Carbon Earth Summit (LCES 2015 & ICE-2015) Theme: "Take Actions for Rebuilding a Clean World" September 24-26, 2015 Venue: Xi'an, China 1

MATHEMATICAL APPENDIX to - lohmander.comlohmander.com/PL_LCES_Ap_2015.pdfThis mathematical appendix includes derivations of most of the results ... dt dt dtdc §·S S S ¨¸ ... In

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MATHEMATICAL APPENDIX to

Optimal continuous cover forest management:- Economic and environmental effects and legal considerations

Professor Dr Peter Lohmander http://www.Lohmander.com

[email protected]

BIT's 5th Low Carbon Earth Summit (LCES 2015 & ICE-2015)

Theme: "Take Actions for Rebuilding a Clean World"

September 24-26, 2015

Venue: Xi'an, China

1

This mathematical appendix includes derivations of most of the results presented in:

”Optimal continuous cover forest management:- Economic and environmental effects and legal considerations”

by

Professor Dr Peter Lohmanderhttp://www.Lohmander.com

[email protected]

BIT's 5th Low Carbon Earth Summit (LCES 2015 & ICE-2015)

Theme: "Take Actions for Rebuilding a Clean World"September 24-26, 2015

Venue: Xi'an, China

2

3

Lohmander 150824 China File

One and two dimensional optimization and comparative statistics in the

volume and time interval dimensions

Peter Lohmander 2015-08-24

One dimensional optimization and comparative statistics in the time interval dimension

General Problem Definition

1 1( , ) ( , )max ( )

1rt

P v t Q v t cR h

e

0 1

. .s t

h v v

Obs: Generalized P(.), Q(.) and R(.). Assumption: r > 0.

4

Derivation of optimal General Principles

2

11 0

1

rt rt

rt

d dP dQQ P e PQ c re

dt dt dte

21 0

1

rtrt

rt

d e dP dQQ P e PQ c r

dt dt dte

2

(.) 01

rt

rt

ek

e

(.) 1 0rtdP dQM Q P e PQ c r

dt dt

(.) 0M

5

(.) 0M

Optimal principles in the time dimension that can be given economic interpretations:

1

1 rt

dP dQQ P

dt dt r

PQ ce

1

rt

rt

dP dQQ P

dt dt rc e PQ

PQe

6

1

1 rt

dP dQQ P r PQ c

dt dt e

1

rt

rt

c e PQdP dQQ P r PQ

dt dt e

1 rt

dP dQQ P

rdt dt

PQ c e

7

Comparative statistics analyses based on one dimensional optimization:

How is the optimal time interval affected if the parameter c marginally increases (ceteres paribus)?

The time intervals are optimized:

0d

dt

If parameter changes take place, we still want the time interval to be optimal:

0d

ddt

8

2 2*

20

d d dd dt dc

dt dt dtdc

2 2*

2

d ddt dc

dt dtdc

2

*

2

2

d

dtdcdt

dc d

dt

A unique optimum is assumed in the time interval dimension. As a consequence:

2

20

d

dt

9

2

(.) 0d

k rdtdc

2

*

2

2

0

d

dtdcdt

dc d

dt

Conclusion:

The optimal time interval is a strictly increasing function of the parameter c.

10

Comparative statistics analyses based on one dimensional optimization:

How is the optimal time interval affected if the parameter r marginally increases (ceteres paribus)?

The time intervals are optimized:

0d

dt

If parameter changes take place, we still want the time interval to be optimal:

0d

ddt

11

2 2*

20

d d dd dt dr

dt dt dtdr

2 2*

2

d ddt dr

dt dtdr

2

*

2

2

d

dtdrdt

dr d

dt

A unique optimum is assumed in the time interval dimension. As a consequence:

2

20

d

dt

12

2

?d

dtdr

2d dk dMM k

dtdr dr dr

2

0 0d d dM

M kdt dtdr dr

2

0 sgn sgnd dM

kdtdr dr

13

(.) 1 0rtdP dQM Q P e PQ c r

dt dt

rtdM dP dQQ P te PQ c

dr dt dt

rtdM dP dQr Q P rte PQ c r

dr dt dt

1rt rtdM dP dQr M Q P rte e

dr dt dt

14

_

0dP dQ

w Q Pdt dt

1rt rtw rte e

_

sgn 0 sgn sgndM

r ww wdr

15

The usual case:

2

0 sgn sgn sgnd dM

r wdtdr dr

1rt rtw rte e

x rt

1x xw xe e

( ) 1 1xw x x e

16

(0) 0w

1 1x xdwe x e

dx

xdwxe

dx

0

0x

dw

dx

0

0x

dw

dx

17

0x rt

0( ) 0

xw x

2

sgn sgn 0d

wdtdr

18

The unusual case:

2

0 sgn sgn sgnd dM

r wdtdr dr

0x rt

0( ) 0

xw x

2

sgn sgn 0d

wdtdr

19

In both cases:

2

0d

dtdr

2

*

2

2

0

d

dtdrdt

dr d

dt

Conclusion:

The optimal time interval is a strictly decreasing function of the parameter r.

20

Comparative statistics analyses based on one dimensional optimization:

How is the optimal time interval affected if the future prices marginally increase (ceteres paribus)?

In order to study the effects of prices on the optimal time interval, useful parameters are needed.

The problem is originally:

1 1( , ) ( , )max ( )

1rt

P v t Q v t cR h

e

Here, we replace this problem by this problem:

1( , )max ( )

1rt

pQ v t cR h

e

21

How is the optimal time interval affected if the parameter p marginally increases (ceteres paribus)?

The time intervals are optimized:

0d

dt

If parameter changes take place, we still want the time interval to be optimal:

0d

ddt

22

2 2*

20

d d dd dt dp

dt dt dtdp

2 2*

2

d ddt dp

dt dtdp

2

*

2

2

d

dtdpdt

dp d

dt

23

A unique optimum is assumed in the time interval dimension. As a consequence:

2

20

d

dt

2

11 0

1

rt rt

rt

d dQp e pQ c re

dt dte

21 0

1

rtrt

rt

d e dQp e pQ c r

dt dte

24

2

(.) 01

rt

rt

ek

e

1(.) 1 0rtdQM p e pQ c r

dt

2

(.) 1 rtd dQk e Q r

dtdp dt

2

(.) 1 rtd dQp k p e pQ r

dtdp dt

25

2

(.)d d

p k crdtdp dt

2

( 0) ( 0) 0 0d d

p crdt dtdp

2

*

2

2

0

d

dtdpdt

dp d

dt

Conclusion:

The optimal time interval is a strictly decreasing function of the parameter p.

26

One dimensional optimization and comparative statistics in the volume dimension

General Problem Definition

1 1( , ) ( , )max ( )

1rt

P v t Q v t cR h

e

0 1

. .s t

h v v

Obs: Generalized P(.), Q(.) and R(.). t > 0. Assumption: r > 0.

27

1 1 1 1

1(.) 0

1rt

d dR dh dP dQQ P

dv dh dv e dv dv

1

1dh

dv

The first order optimum condition implies:

1 1

1(.)

1rt

dR dP dQQ P

dh e dv dv

28

Assumption: A unique maximum in the volume dimension:

2

2

1

0d

dv

Assumption:

0dR

dh

1 1 1

0 0 0 (.) 0dR d dP dQ

rt Q Pdh dv dv dv

Assumption:

2

1 1 1

(.) 01

rt

rt

d e dP dQQ P

dv dr e dv dv

29

Comparative statistics analyses based on one dimensional optimization:

How is the optimal volume affected if the parameter r marginally increases (ceteres paribus)?

The volume is optimized:

1

0d

dv

If parameter changes take place, we still want the volume to be optimal:

1

0d

ddv

30

2 2*

12

1 1 1

0d d d

d dv drdv dv dv dr

2 2*

12

1 1

0d d

dv drdv dv dr

2 2

*

12

1 1

d ddv dr

dv dv dr

2

*11

2

2

1

0

d

dv drdv

dr d

dv

Conclusion:

The optimal volume is a strictly decreasing function of the parameter r.

31

Comparative statistics analyses based on one dimensional optimization:

How is the optimal volume affected if the future prices marginally increase (ceteres paribus)?

In order to study the effects of prices on the optimal time interval, useful parameters are needed.

The problem is originally:

1 1( , ) ( , )max ( )

1rt

P v t Q v t cR h

e

Here, we replace this problem by this problem:

1( , )max ( )

1rt

pQ v t cR h

e

32

1 1 1

10

1rt

d dR dh dQp

dv dh dv e dv

2

1 1

1

1rt

d dQ

dv dp e dv

The first order optimum condition implies:

1

1

1rt

dR dQp

dh e dv

Assumption: A unique maximum in the volume dimension:

2

2

1

0d

dv

33

Assumption:

0dR

dh

1 1

10 0 0 0 0

1rt

dR d dQrt p

dh dv e dv

2

1 1

10

1rt

d dQ

dv dp e dv

2 2*

12

1 1 1

0d d d

d dv dpdv dv dv dp

34

2 2*

12

1 1

0d d

dv dpdv dv dp

2 2

*

12

1 1

d ddv dp

dv dv dp

2

*11

2

2

1

0

d

dv dpdv

dp d

dv

Conclusion:

The optimal volume is a strictly increasing function of the parameter p.

35

Comparative statistics analyses based on one dimensional optimization:

How is the optimal volume affected if the parameter c marginally increases (ceteres paribus)?

2 2*

12

1 1

0d d

dv dcdv dv dc

2

*11

2 2

2 2

1 1

00

d

dv dcdv

dc d d

dv dv

Conclusion:

The optimal volume is not affected by changes of the parameter c.

36

Observation:

If the volume is constrained (by law or something else), we may study the effects of the volume

constraint on the optimal time interval, via one dimensional optimization and

comparative statics using 2

1

d

dv dt

.

Also, since 2 2

1 1

d d

dv dt dtdv

, we may perform the corresponding analysis of optimal volume based on

constrained t.

In both cases, it is necessary to know somehing about 2

1

d

dv dt

.

Below, we will also use 2

1

d

dv dt

in another way, in two dimensional optimization of the time interval

and the volume.

37

We will soon discover that 2

1

0d

dv dt

.

In ”one dimensional optimization” and comparative statics analysis, we come to the following

conclusions:

2

*1

21

2

0

d

dtdvdt

dv d

dt

and

2

*11

2

2

1

0

d

dv dtdv

dt d

dv

38

Two dimensional optimization and comparative statistics in the volume and

time interval dimensions

General Problem Definition

1( , )max ( )

1rt

pQ v t cR h

e

0 1

. .s t

h v v

39

The first order optimum conditions:

1

0

0

d

dv

d

dt

1 1

2

10

1

1 01

rt

rtrt

rt

dR dh dQp

dh dv e dv

e dQp e pQ c r

dte

40

Assumption: A unique maximum exists. The following conditions hold:

2 2

22 21 1

2 2 2 21

2

1

0, 0, 0

d d

dv dv dtd d

dv dt d d

dtdv dt

For a unique maximum, it is sufficient that:

2 2

221 1

2 2 21

2

1

0, 0

d d

dv dv dtd

dv d d

dtdv dt

41

In the analysis, it will turn out that it is important to know something about

2 2

1 1

d d

dv dt dtdv

, at least the sign.

2 2

2 2 2 2 21 1

2 22 21 1 1

2

1

0 0

d d

dv dv dt d d d dD

dv dt dtdv dv dtd d

dtdv dt

42

22 2 2 2 2

2 2

1 1 1 1

d d d d d

dv dt dtdv dv dt dv dt

Observation:

22

1

d

dv dt

is usually small in relation to 2 2

2 2

1

d d

dv dt

.

2

1

d

dv dt

is however a function of several parameters

and decision variables, which makes it complicated to give general and explicit functions describing

the signs and absolute values of 2

1

d

dv dt

. In any case, the sign of

2

1

d

dv dt

will be determined.

43

Determination of the sign of 2

1

d

dv dt

:

1 1

10

1rt

d dR dQp

dv dh e dv

2 2

2

1 1 1

1

11

rt

rtrt

d re dQ d Qp p

dv dt dv e dv dte

44

2 2

1 1 11 1rt rt

d p d Q r dQ

dv dt e dtdv e dv

2

11 0

1

rt rt

rt

d dQp e pQ c re

dt dte

2 2

1 1 11 1rt rt

d p d Q r dQ

dtdv e dtdv e dv

45

Observation:

2 2 2

1 1 1 11 1rt rt

d d p d Q r dQ

dv dt dtdv e dtdv e dv

2

1

sgn sgnd

dv dt

2

1 11 rt

d Q r dQ

dv dt e dv

46

With relevant growth functions:

2 2

1 10

td Q d Q

ds tdv dt dv dt

2

1 10

td Q dQ

dsdv dt dv

2

1 1

d Q dQt

dv dt dv

21

1

, 0

dQ

dvd Qk k

dv dt t

47

2

1 11 rt

d Q r dQ

dv dt e dv

1

11 rt

dQ

dv r dQk

t e dv

1

1

1 rt

dQ rk

dv t e

Observation:

1

10 sgn sgn

1 rt

dQ rk

dv t e

48

Let 1 rt

rw

e

W(r=0) = ? Observation: Division by zero is not allowed.

0

1 1lim

1 1rt rtrtr

dr

r dr

e te td e

dr

01 1

1 1lim 0r

dQ dQk k

dv t t dv

49

1

1

1 rt

dQ rk

dv t e

2

1

1(1 )

1

rt rt

rt

e r ted dQ

dr dv e

2

1

11

1

rt rt

rt

d dQe rte

dr dv e

50

Let

1 (1 )rte rt

Observation:

sgn sgnd

dr

( 0) 0r

(1 )rt rtdte rt e t

dr

2 rtdrt e

dr

51

0 0 0d

r tdr

0 0 0r t

sgn sgnd

dr

0d

dr

52

0

lim 0 0 0r

d

dr

2

1

sgn sgnd

dv dt

2

1

0d

dv dt

53

Comparative statics analysis based on two dimensional optimization:

2 2 2 2 2

2 *1 1 1 1 11

*2 2 2 2 2

2

1

d d d d ddc dp dr

dv dv dt dv dc dv dp dv drdv

dtd d d d ddc dp dr

dtdv dt dtdc dtdp dtdr

54

First, we study the effects of changes in c , when 0dp dr .

2

1

0d

dv dc

2

20

1

rt

rt

d re

dtdc e

55

2 2 2

2 *1 1 1 1

*2 2 2

2

1

d d ddc

dv dv dt dv dv dc

dtd d ddc

dtdv dt dtdc

2 2 2 2

1 1 1 1

2 2 2 2

* 2 21

2 2

2

1 1

2 2

2

1

d d d d

dv dc dv dt dv dc dv dt

d d d d

dv dtdc dt dtdc dt

dc Dd d

dv dv dt

d d

dtdv dt

56

2

1

2 22 2

* 21 1

0d

dv dt

d dd d

dv dtdc dv dtdtdc dt

dc D D

*2 2

1

1

0 0 sgn sgndvd d

Ddtdc dc dv dt

Observation:

2

1

0d

dv dt

. As a consequence,

*

1 0dv

dc .

57

2 2 2

2 2

1 1 1

2 2 2 2 2 2

2*1 1 1

2 2

2

1 1

2 2

2

1

0

0

d d d

dv dv dc dv

d d d d d d

dtdv dtdc dtdv dtdc dv dtdcdt

dc D Dd d

dv dv dt

d d

dtdv dt

58

Second, we study the effects of changes in p , when 0dc dr .

2

1 1

10

1rt

d dQ

dv dp e dv

2

2

11

1

rt rt

rt

d dQe Q re

dtdp dte

2

2

11

1

rt rt

rt

d dQp p e pQ re

dtdp dte

59

2

2

10

1

rt

rt

d dp cre

dtdp dt e

2

0 0 0d d

pdt dtdp

2 2 2

2 *1 1 11

*2 2 2

2

1

d d ddp

dv dv dt dv dpdv

dtd d ddp

dtdv dt dtdp

60

2 2 2 2

1 1 1 1

2 2 2 2

2 2*

1

2 2

2

1 1

2 2

2

1

d d d d

dv dp dv dt dv dp dv dt

d d d d

dtdp dt dtdp dtdv

dp Dd d

dv dv dt

d d

dtdv dt

2 2

1 1

2 2 2 2 2 2

2* 2

1 1 1 0

d d

dv dp dv dt

d d d d d d

dtdp dtdv dv dp dt dtdp dv dt

dp D D

61

2 2

2

1 1

2 2 2 2 2 2

2*1 1 1 1 0

d d

dv dv dp

d d d d d d

dtdv dtdp dv dtdp dtdv dv dpdt

dp D D

62

Third, we study the effects of changes in r , when 0dc dp .

2

1

2

1

01

rt

rt

dQpte

dvd

dv dr e

We have already determined that that:

2

0d

dtdr

2 2 2

2 *1 1 1 1

*2 2 2

2

1

d d ddr

dv dv dt dv dv dr

dtd d ddr

dtdv dt dtdr

63

2 2 2 2

1 1 1 1

2 2 2 2

* 2 21

2 2

2

1 1

2 2

2

1

d d d d

dv dr dv dt dv dr dv dt

d d d d

dv dtdr dt dtdr dt

dr Dd d

dv dv dt

d d

dtdv dt

2 2

1 1

2 2 2 22 2

* 221 1 1

d d

dv dr dv dt

d d d dd d

dv dv dr dt dtdr dv dtdtdr dt

dr D D

2

1

d

dv dt

is negative but has a low absolute value. As a result:

*

1 0dv

dr

64

2 2

2

1 1

2 2 2 2 2 2

2*1 1 1 1

2 2

2

1 1

2 2

2

1

d d

dv dv dr

d d d d d d

dtdv dtdr dv dtdr dtdv dv drdt

dr Dd d

dv dv dt

d d

dtdv dt

2

1

d

dv dt

is negative but has a low absolute value. As a result:

*

0dt

dr

Optimal continuous cover forest management

First, we study:

One dimensional optimization inthe time interval dimension

(of relevance when the stock levelafter harvest is determined by law

or can not be determined for some other reason)

65

66

1 1( , ) ( , )max ( )

1rt

P v t Q v t cR h

e

0 1

. .s t

h v v

67

21 0

1

rtrt

rt

d e dP dQQ P e PQ c r

dt dt dte

1 0rtdP dQQ P e PQ c r

dt dt

(.) 0M

Optimal principle in the time dimension:

68

1

rt

rt

dP dQQ P

dt dt rc e PQ

PQe

How is the optimal time interval affected if the parameter c marginally increases (ceteresparibus)?

69

0d

dt

2 2*

20

d d dd dt dc

dt dt dtdc

2

*

2

2

d

dtdcdt

dc d

dt

A unique optimum is assumed in the time interval dimension

70

2

20

d

dt

2

(.) 0d

k rdtdc

2

*

2

2

0

d

dtdcdt

dc d

dt

Conclusion:

The optimal time interval

is a strictly increasing

function of c.

How is the optimal time interval affected if the parameter r marginally increases (ceteres paribus)?

71

2

*

2

2

0

d

dtdrdt

dr d

dt

Conclusion:

The optimal time interval is

a strictly decreasing function

of the parameter r.

How is the optimal time interval affected if the future prices marginally increase (ceteres paribus)?

72

1( , )max ( )

1rt

pQ v t cR h

e

73

2

*

2

2

0

d

dtdpdt

dp d

dt

Conclusion:

The optimal time interval is a

strictly decreasing function of the

parameter p.

Optimal continuous cover forest management

Now, we study:

One dimensional optimization inthe volume dimension

(of relevance when the time interval is determined by law

or can not be determined for some other reason)

74

75

1 1( , ) ( , )max ( )

1rt

P v t Q v t cR h

e

0 1

. .s t

h v v

76

1 1 1 1

1(.) 0

1rt

d dR dh dP dQQ P

dv dh dv e dv dv

1

1dh

dv

1 1

1(.)

1rt

dR dP dQQ P

dh e dv dv

Optimal principle in the

volume dimension:

How is the optimal volume affected if one

parameter marginally increases (ceteres

paribus)?

- The optimal volume is not affected by changes of c.

- The optimal volume is a strictly decreasing function of r.

- The optimal volume is a strictly increasing function of p.

77

Observation:

• If the volume is constrained (by law or something else), we may studythe effects of the volume constraint on the optimal time interval, via one dimensional optimization.

78

2

1

0d

dv dt

2

*1

21

2

0

d

dtdvdt

dv d

dt

Observation (extended):

• If the time interval is constrained (by law or something else), we maystudy the effects of the time interval constraint on the volume, via onedimensional optimization.

79

2

*11

2

2

1

0

d

dv dtdv

dt d

dv

2

1

0d

dv dt

Optimal continuous cover forest management

Now, we study:

Two dimensional optimization in the volume AND time interval dimensions

80

81

1( , )max ( )

1rt

pQ v t cR h

e

0 1

. .s t

h v v

The first order optimum conditions:

82

1

0

0

d

dv

d

dt

1 1

2

10

1

1 01

rt

rtrt

rt

dR dh dQp

dh dv e dv

e dQp e pQ c r

dte

Assumption: A unique maximum exists. The

following conditions hold:

83

2 2

22 21 1

2 2 2 21

2

1

0, 0, 0

d d

dv dv dtd d

dv dt d d

dtdv dt

84

2 2

2 2 2 2 21 1

2 22 21 1 1

2

1

0 0

d d

dv dv dt d d d dD

dv dt dtdv dv dtd d

dtdv dt

22 2 2 2 2

2 2

1 1 1 1

d d d d d

dv dt dtdv dv dt dv dt

Comparative statics analysis based on two

dimensional optimization:

85

2 2 2 2 2

2 *1 1 1 1 11

*2 2 2 2 2

2

1

d d d d ddc dp dr

dv dv dt dv dc dv dp dv drdv

dtd d d d ddc dp dr

dtdv dt dtdc dtdp dtdr

86

2 2 2

2 *1 1 1 1

*2 2 2

2

1

d d ddc

dv dv dt dv dv dc

dtd d ddc

dtdv dt dtdc

87

2

1

2 22 2

* 21 1

0

0

d

dv dt

d dd d

dv dtdc dv dtdtdc dt

dc D D

88

2 2 2

2 2

1 1 1

2 2 2 2 2 2

2*1 1 1

2 2

2

1 1

2 2

2

1

0

0

d d d

dv dv dc dv

d d d d d d

dtdv dtdc dtdv dtdc dv dtdcdt

dc D Dd d

dv dv dt

d d

dtdv dt

89

2 2

1 1

2 2 2 2 2 2

2* 2

1 1 1 0

d d

dv dp dv dt

d d d d d d

dtdp dtdv dv dp dt dtdp dv dt

dp D D

90

2 2

2

1 1

2 2 2 2 2 2

2*1 1 1 1 0

d d

dv dv dp

d d d d d d

dtdv dtdp dv dtdp dtdv dv dpdt

dp D D

91

2 2

1 1

2 2 2 22 2

* 221 1 1 0

d d

dv dr dv dt

d d d dd d

dv dv dr dt dtdr dv dtdtdr dt

dr D D

92

2 2

2

1 1

2 2 2 2 2 2

2*1 1 1 1

2 2

2

1 1

2 2

2

1

0

d d

dv dv dr

d d d d d d

dtdv dtdr dv dtdr dtdv dv drdt

dr Dd d

dv dv dt

d d

dtdv dt

93

Graphical

illustrations

based on

specified

functions

and

parameters

94

tv1

Present

value

95

Present

value

tv1

96

Present

value

tv1

97

Present

value

t

v1

98

99

100

Case c = 25:

Local optimal solution found.

Objective value: 6112.837

Infeasibilities: 0.1421085E-13

Total solver iterations: 33

Variable Value Reduced Cost

V0 200.0000 0.000000

P 20.00000 0.000000

C 25.00000 0.000000

R 0.3000000E-01 0.000000

M0 30.00000 0.000000

C0 50.00000 0.000000

Y 6112.837 0.000000

R0 4614.702 0.000000

Q 60.39070 0.000000

T 19.39833 0.000000

H 148.8702 0.000000

V1 51.12982 0.000000

MP 20.35565 0.000000

A -0.1833333 0.000000

B 0.1666667E-02 0.000000

101

Case c = 75:

Local optimal solution found.

Objective value: 6059.922

Infeasibilities: 0.1818989E-11

Total solver iterations: 36

Variable Value Reduced Cost

V0 200.0000 0.000000

P 20.00000 0.000000

C 75.00000 0.000000

R 0.3000000E-01 0.000000

M0 30.00000 0.000000

C0 50.00000 0.000000

Y 6059.922 0.000000

R0 4678.431 0.000000

Q 79.22597 0.000000

T 24.61475 0.000000

H 152.0811 0.000000

V1 47.91893 0.000000

MP 19.33378 0.000000

A -0.1833333 0.000000

B 0.1666667E-02 0.000000

102

Case r = 0.01:

Local optimal solution found.

Objective value: 11288.77

Infeasibilities: 0.1818989E-11

Total solver iterations: 39

Variable Value Reduced Cost

V0 200.0000 0.000000

P 20.00000 0.000000

C 50.00000 0.000000

R 0.1000000E-01 0.000000

M0 30.00000 0.000000

C0 50.00000 0.000000

Y 11288.77 0.000000

R0 3708.662 0.000000

Q 122.3903 0.000000

T 27.48465 0.000000

H 112.9925 0.000000

V1 87.00750 0.000000

MP 29.43645 0.000000

A -0.1833333 0.000000

B 0.1666667E-02 0.000000

103

Case r = 0.05:

Local optimal solution found.

Objective value: 5438.774

Infeasibilities: 0.1421085E-13

Total solver iterations: 31

Variable Value Reduced Cost

V0 200.0000 0.000000

P 20.00000 0.000000

C 50.00000 0.000000

R 0.5000000E-01 0.000000

M0 30.00000 0.000000

C0 50.00000 0.000000

Y 5438.774 0.000000

R0 4935.135 0.000000

Q 30.30823 -0.2519769E-08

T 14.87958 0.1972276E-07

H 167.4356 0.000000

V1 32.56436 0.000000

MP 13.97205 0.000000

A -0.1833333 0.000000

B 0.1666667E-02 0.000000

104

Case p= 15:

Local optimal solution found.

Objective value: 5744.222

Infeasibilities: 0.1421085E-13

Total solver iterations: 33

Variable Value Reduced Cost

V0 200.0000 0.000000

P 15.00000 0.000000

C 50.00000 0.000000

R 0.3000000E-01 0.000000

M0 30.00000 0.000000

C0 50.00000 0.000000

Y 5744.222 0.000000

R0 4855.214 0.000000

Q 87.63010 0.000000

T 29.49081 0.2944944E-08

H 162.0924 0.000000

V1 37.90758 0.000000

MP 15.92702 0.000000

A -0.1833333 0.000000

B 0.1666667E-02 0.000000

105

Case p = 25:

Local optimal solution found.

Objective value: 6485.002

Infeasibilities: 0.9094947E-12

Total solver iterations: 33

Variable Value Reduced Cost

V0 200.0000 0.000000

P 25.00000 0.000000

C 50.00000 0.000000

R 0.3000000E-01 0.000000

M0 30.00000 0.000000

C0 50.00000 0.000000

Y 6485.002 0.000000

R0 4412.308 0.000000

Q 58.10996 0.000000

T 17.22910 0.000000

H 139.5701 0.000000

V1 60.42991 0.2916067E-08

MP 23.12150 0.000000

A -0.1833333 0.000000

B 0.1666667E-02 0.000000

106

Case m0 = 25:

Local optimal solution found.

Objective value: 5358.305

Infeasibilities: 0.9094947E-12

Total solver iterations: 39

Variable Value Reduced Cost

V0 200.0000 0.000000

P 20.00000 0.000000

C 50.00000 0.000000

R 0.3000000E-01 0.000000

M0 25.00000 0.000000

C0 50.00000 0.000000

Y 5358.305 0.000000

R0 3713.153 0.000000

Q 61.67188 0.000000

T 18.06485 0.000000

H 139.4981 0.000000

V1 60.50189 0.000000

MP 18.14178 0.000000

A -0.1833333 0.000000

B 0.1666667E-02 0.000000

107

Case m0 = 35:

Local optimal solution found.

Objective value: 6863.473

Infeasibilities: 0.9094947E-12

Total solver iterations: 35

Variable Value Reduced Cost

V0 200.0000 0.000000

P 20.00000 0.000000

C 50.00000 0.000000

R 0.3000000E-01 0.000000

M0 35.00000 0.000000

C0 50.00000 0.000000

Y 6863.473 0.000000

R0 5637.867 0.000000

Q 82.08137 0.000000

T 27.74400 0.000000

H 160.7782 0.000000

V1 39.22175 0.000000

MP 21.39327 0.000000

A -0.1833333 0.000000

B 0.1666667E-02 0.000000

The following pages include general second order conditions with notation following Chiang, A., Fundamental methods of mathematical economics, McGraw-Hill, 2 ed., 1974

108

Appendix:

On the second order total differential and the second order maximum and minimum conditions:

2 2 2

xx xy yx yyd z f dx f dxdy f dydx f dy

2 2 22xx xy yyd z f dx f dxdy f dy

2 22q au huv bv

109

2 22q au huv bv

2 22 2 2 22

h hq au huv v bv v

a a

2 22 2 2

2

2h h hq a u uv v b v

a a a

2 22h ab h

q a u v va a

110

Results:

If: 20 0 0a ab h q , the quadratic form is said to be negative definite.

If: 20 0 0a ab h q , the quadratic form is said to be positive definite.

In other words: Assumption: A unique (local) maximum exists. The following conditions hold:

2 2

22 2

2 2 2 2

2

0, 0, 0

d f d f

dx dxdyd f d f

dx dy d f d f

dydx dy

111

For a unique (local) maximum, it is sufficient that:

2 2

22

2 2 2

2

0, 0

d f d f

dx dxdyd f

dx d f d f

dydx dy

For a unique (local) minimum, it is sufficient that:

2 2

22

2 2 2

2

0, 0

d f d f

dx dxdyd f

dx d f d f

dydx dy

MATHEMATICAL APPENDIX to

Optimal continuous cover forest management:- Economic and environmental effects and legal considerations

Professor Dr Peter Lohmander http://www.Lohmander.com

[email protected]

BIT's 5th Low Carbon Earth Summit (LCES 2015 & ICE-2015)

Theme: "Take Actions for Rebuilding a Clean World"

September 24-26, 2015

Venue: Xi'an, China

112