er
ch
s ha
pre
e ap
has
rspe
e of
oundings. The synergy multiplication coefficient is introduced into the evaluation
o study
s the e
ection,
evaluation approach, contemporary option-based asset evaluation the perspective of real optionswith reference to the analyses proposed
Economic Modelling 28 (2011) 1587–1594
Contents lists available at ScienceDirect
Economic M
e ls
approach, and the integrationof the above-mentioned approaches. It is
obvious that the pricing of the target enterprise of M&A is a critically
hot topic that has remained unsolved due to the uncertain surround-
ings of M&A. The existing evaluation approaches can be classified in
three categories: (1) the traditional NPV-based approaches, such as
the Rappaport model (Rappaport, 1998), Weston formula method
(Weston and Thomas, 1992),and others; (2) models based on the
perspective of real options (Black and Scholes, 1973; Lambrecht, 2003;
McDonald and Siegel, 1984; Merton, 1977; Smith et al., 1995); and (3)
models based on the game perspective (Burkart, 1995; Farrell and
by Dixit (Dixit and Pindyck, 1994). We then investigate how to price
the target enterprise by using the famous Rubinstein offer–counter-
offer theorem, which is improved for adaptation to the assumed
stochastic surroundings of M&A. The price formula of target enterprise
of M&A is then developed and some corresponding simulations show
the interpretation power of price formula to reality.
The rest of this paper is organized as follows. Section 2 discusses
how to evaluate the target enterprise of M&A from the perspective of
real options. How to price the target enterprise of M&A is investigated
in detail in Section 3. Some simulations are drawn to show how well
Shapiro, 1990; Grossman and Hart, 1980; Hir
Though extant literatures have investigated t
enterprises from the integration perspective
⁎ Corresponding author. Tel.: +86 10 62288613.
E-mail addresses: yujing3721@163.com (J. Yu), zhuo
(B. Xu).
0264-9993/$ – see front matter © 2011 Elsevier B.V. Al
doi:10.1016/j.econmod.2011.02.034
and so on. In addition,
eveloped to reveal the
value (NPV)-based asset
solution can be found in two critical factors: how to evaluate the target
enterprise of M&A and how to price the target enterprise of M&A. This
paper discusses the evaluation of the target enterprise of M&A from
many innovative approaches have been d
essence of M&A such as classical net present
1. Introduction
There are many extant literatures t
(M&A), in which the research include
factor analyses, target enterprise sel
surroundings. The price formula is further discussed on condition that the operating cost is more than or less
than profit flow, which is assumed to follow geometric Brownian motion process. The numeric simulations
show that the proposed formulas in this paper can perfectly well reflect the realistic practice of M&A.
© 2011 Elsevier B.V. All rights reserved.
merger and acquisition
valuation model, impact
approaches, simply using the famous Rubinstein offer–counteroffer
theorem to attain the price of the target enterprise has caused
imperfectly dynamic analyses process and the corresponding unprac-
tical price result in the distortion of M&A reality. The key to the
shleifer and Ping, 1990).
he pricing of M&A target
of the above-mentioned
the proposed pr
Section 5 conclu
the future are pr
2. Evaluating th
Generally spe
composed of tw
hongxubin@hotmail.com
l rights reserved.
in theorem, which is improved to fit for the stochastic
Game theory
Merger and acquisition
model to reflect the synergy management process of M&A, and the equilibrium price formula is proposed by
applying the famous offer–counteroffer Rubinste
Real option perspective
to price the target enterpris
theory under stochastic surr
The game analyses to price the target ent
the perspective of real options under sto
Jing Yu a,c, Bin Xu b,⁎
a School of International Auditing,Nanjing Audit University,211815,Nanjing,China
b School of Accountancy,Central University of Finance and Economics,100081,Beijing,China
c Research Center of Fictitious Economy and Data Science,CAS,100190,Beijing,China
a b s t r a c ta r t i c l e i n f o
Article history:
Accepted 10 February 2011
Keywords:
Decision analysis
Asset pricing
Although several approache
(M&A) such as classical net
pricing processes in all thes
target enterprise of M&A
perspective, real options pe
j ourna l homepage: www.
prise of merger and acquisition based on
astic surroundings
ve been developed to evaluate the target enterprise of merger and acquisition
sent value (NPV) evaluation model and real options techniques, the logic of
proaches is still faulty. The classical approach of NPV perspective to price the
been replaced by integration of contemporary perspectives such as NPV
ctive, game perspective, and so on. In this paper, the dynamic analyses model
M&A is developed from the perspective of real options integrated with game
odelling
ev ie r.com/ locate /ecmod
ice formulas match the reality of M&A in Section 4.
des the paper and some possible research direction in
oposed.
e target enterprise of M&A
aking, in this paper, the value of target enterprise is
o parts from the perspective of real options: the
delling 28 (2011) 1587–1594
intrinsic value and its corresponding implied value. The former can be
calculated based on the future forecasted cash flow in its sustainable
operating life cycle, which covers the whole operating process of
target enterprise after M&A, while the latter can be measured by its
corresponding real option values.
Hereafter, the value of the target enterprise is equal to the
summation of the above two mentioned parts without considering
the synergy effect of M&A, which is introduced into the above
summation model for a time. The following parts in this section
demonstrate how to develop in detail the evaluation formula
according to the above-proposed idea.
2.1. Evaluating the intrinsic value of target enterprise of M&A
For convenience, it is assumed that there are only two players in
the M&A process: the merger or acquiring enterprise and the merged
or acquired enterprise. They can be denoted as A and T respectively.
Dixit (1989) (Dixit and Pindyck, 1994) proposed an innovative idea to
measure the intrinsic value of enterprise and its corresponding
implied value of real options, which allows us to measure the value of
the above two mentioned parts. For convenience, the main content of
deducing process in literature (Dixit, 1989; Dixit and Pindyck, 1994) is
compactly introduced in this section.
Assume P to denote the future profit flow of the target enterprise,
which follows geometric Brownian motion process (Cox and Miller,
1965; Dixit, 1991; Dixit and Pindyck, 1994; Hull, 1989; Merton, 1971)
dP = αPdt + σPdz ð1Þ
where, the profit flow P increases with a velocity of α, which also
denotes the drifting coefficient, σ denotes fluctuation rate, and dz
denotes increment of Weiner stochastic process dz =
ffiffiffiffiffi
dt
p
. It is
apparent that if the foreseeable future profit flow P is discounted by
μ, the intrinsic value of T can be formulated as V = P= μ−αð Þ. We can
then conclude that the intrinsic value V also follows geometric
Brownian motion process with the same drifting coefficient α and the
same fluctuation rate σ.
Based on Capital Asset Pricing Model (CAPM) formulation, we
have the following formula:
μ = r + ϕσρpm ð2Þ
where δ=μ−α, the symbol r denotes the discount rate without risk,
ρpm denotes the correlation coefficient between the market portfolio
and the asset of tracking profit flow P, and ϕ denotes risk rate. As
V = P= μ−αð Þ is forever positive, the inequality μNαmust be assumed.
Without the loss of generality, we assume that the intrinsic value V of
T is only the function of profit flow P with its operating cost C. Thus, the
increment of profit flow P is exactly formulated as π(P)=max(P−C,0).
Based on the ITO lemma together with the feature of risk free portfolio
(Dixit, 1991; 1992; Dixit and Pindyck, 1994; Pindyck, 1991), the
following equation can be deduced:
1
2
σ2P2V ″ Pð Þ + r−δð ÞV′ Pð Þ−rV Pð Þ + π Pð Þ = 0: ð3Þ
Thus, the solution of Eq. (3) can be obtained on condition that PbC
and PNC, respectively. Details on the solving process can be seen from
the literature (Dixit and Pindyck, 1994).
If PbC, the solution can be formulated as:
V Pð Þ = K1Pβ1 + K2Pβ2 ; ð4Þ
and if PNC, the solution can also be formulated as
V Pð Þ = B1Pβ1 + B2Pβ2 +
P−C ð5Þ
1588 J. Yu, B. Xu / Economic Mo
δ r
where,
β1 =
1
2
− r−δ
σ2
+
ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
r−δ
σ2
−1
2
� �2
+
2r
σ2
s
N 1 ð6:1Þ
β2 =
1
2
− r−δ
σ2
−
ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
r−δ
σ2
−1
2
� �2
+
2r
σ2
s
b 0: ð6:2Þ
The coefficients K1,K2 and B1,B2 are undetermined, which can be
solved based on boundary conditions, and their general solutions can
be expressed as
V Pð Þ =
K1P
β1 ; P b C
B2P
β2 +
P
δ
−C
r
; P N C
8><
>: ð7Þ
where,
K1 =
C1−β1
β1−β2
β2
r
−β2−1
δ
� �
B2 =
C1−β2
β1−β2
β1
r
−β1−1
δ
� � ð8Þ
which is clearly K1N0, B2N0 and rNβ1(r−δ), rNβ2(r−δ).
2.2. Evaluating the implied value of target enterprise of M&A
Measuring the optionvalueof target enterprise is investigated in this
subsection. We can directly reference the formulation from the
literatures (Dixit, 1991; 1992; Merton, 1973; 1977; 1971; Pindyck,
1991).
F Pð Þ = A1Pβ1 + A2Pβ2 ð9Þ
From literatures (Dixit, 1989; 1991; 1992; Dixit and Pindyck, 1994),
both values match the condition and the smooth paste condition at the
optimum critical point P*, which can be expressed as follows:
F P�ð Þ = V P�ð Þ−I
F′ P�ð Þ = V′ P�ð Þ ð10Þ
where A1,A2 are undetermined coefficients, I denotes initial investment
cost. Substituting Eqs. (7) and (9) into Eq. (10), we have following:
A1 P
�ð Þβ1 = B2 P�ð Þβ2 +
P�
δ
−C
r
−I
β1A1 P
�ð Þβ1−1 = β2B2 P�ð Þβ2−1 +
1
δ
:
ð11Þ
It is apparent that the coefficient B2 can be known from Eq. (8);
therefore, the coefficients A1 and P* can be solved. Eq. (11) at the
critical point P* can be transferred to
β1−β2ð ÞB2 P�
� �β2 + β1−1ð ÞP�
δ
− β1
C
r
+ I
� �
= 0: ð12Þ
Unfortunately, it is difficult to acquire the analytic expression of
solutions P*,A1 except for some special coefficients β1,β2.
1589J. Yu, B. Xu / Economic Modelling 28 (2011) 1587–1594
2.3. Measuring the synergy effect of M&A
From Subsections 2.1 and 2.2, the value G(P) of target enterprise
can be formulated as
G Pð Þ = V Pð Þ + F Pð Þ =
(
F Pð Þ + K1Pβ1 ; P b C
F Pð Þ + B2Pβ2 +
P
δ
−C
r
; P N C
=
A1P
β1 + K1P
β1 ; P b C
A1P
β1 + B2P
β2 +
P
δ
−C
r
; P N C
:
8><
>:
ð13Þ
It is obviously improper not to consider the synergy effect of M&A
in Eq. (13), which is improved to reflect the synergy effect. In fact, the
synergy coefficient λ(t) is a function of time t (tN0), which covers the
sustainable operating life cycle of the target enterprise.
Generally speaking, the positive synergy effect of M&A can be
visually expressed as 1+1N2, which means λ(t)N1; whereas the
negative synergy effect can also be visually expressed as 1+1b2,
which means 0bλ(t)b1. It is obvious that the phenomena λ(t)≤0
would not occur in real practice. Based on the practice of M&A, the
synergy multiplication λ(t) is less than 1 at the beginning of M&A
because of the management entrenchment existing in the process of
M&A, and the positive synergy effect λ(t)N1 occurs after M&A due to
entrenchment lessening with the progress of M&A.
The function λ(t)=λ ln(t+1) (λN0, tN0) can obviously reflect the
feature of the process of M&A owing to the function chart trend
changing from small to big as time goes on. Hence, it is reasonable to
be selected as the synergy effective function. Thus, the formulation
(13) can be transformed to the following:
G Pð Þ = λ tð Þ V Pð Þ + F Pð Þð Þ = λ ln t + 1ð Þ V Pð Þ + F Pð Þð Þ: ð14Þ
Many types of functions can be selected as the synergy effect
function as long as they can adequately approximate the synergy
effective process of M&A according to the real practice of M&A. While
different functions can be selected as synergy effect functions, the
expressions of the equilibrium price proposed next may be different.
The deduced idea must be the same as our deduced analysis. In other
words, the deduced process in this paper does not lose the generality of
guiding the practitioners to price the target enterprise in M&A.
3. Pricing the target enterprise of M&A
3.1. Preliminary theorems
The process of pricing the target enterprise of M&A can be divided
into two main phases: evaluation and pricing of the target enterprise.
The first phase has been accomplished in Section 2; therefore, how to
price the target enterprise is the main task in this section. It is
apparent that merger/acquisition enterprise and its opposite merged/
acquired enterprise can be taken as two players in one game, and the
two players play an offer–counteroffer game to attain the equilibrium
price of the target enterprise of M&A. The classical Rubinstein
theorem can be directly applied to attain the equilibrium price
under certain surroundings. Unfortunately, the stochastic surround-
ings localized here cannot satisfy the preliminary condition of
Rubinstein equilibrium theorem because the game target value is of
uniform distribution, which is crucial to prove the Rubinstein theorem
in the following proof. Thus, it is necessary to improve the Rubinstein
theorem to fit the stochastic surroundings.
In order to smoothly understand the proposed improved Rubin-
stein theorem, the detailed proof process of classical Rubinstein
theorem, which is strictly different from that of Shaked and Sutton
(1984) in this section, is again proven. The following several
corollaries are then deduced to get the equilibrium price of target
enterprise M&A under different stochastic surroundings.
Theorem 1. (Rubinstein, 1982): Under the unlimited times of alternat-
ing offer–counteroffer game, the only NASH perfect equilibrium solution
of sub-game can be formulated as
x� =
1−θ2
1−θ1θ2
If θ1 = θ1 = θ; x
� =
1
1 + θ
where x* denotes the share of first mover player, 1−x* denotes that of
last mover player, the symbols θ1,θ2 denote their corresponding discount
rates respectively.
Theorem 1 tells us how to carve up the target value by deciding
their corresponding shares. In this paper, the following discloses an
inarguable fact implied in this theorem, which has long been ignored
intentionally or unintentionally. The fact is that the target value is of
uniform distribution in the closed interval [0, 1]. To illustrate the
importance of the implied fact, this study again proves the theorem to
illustrate the rationality of the above-hypothesized implied fact. The
improved proof process is based on that of Shaked and Sutton (1984).
Proof. Assume that the target value ξ is of uniform distribution in the
closed interval [0, 1], which density function can be expressed as
f xð Þ = 1; x∈ 0;1½ �0; x∉ 0;1½ � :
�
There are two players designated as Player 1 (first-move player)
and Player 2 (last-move player). Their strategy spaces can be
represented as S1={(0,M)|0≤M≤1} and S2={(M, 1)|0≤M≤1},
where M denotes the maximum attainable share for Player 1. Their
payoff functions can be represented as P{x≤M} and 1−P{x≤M},
which are equal to P{x≥1−M} without regard to their corresponding
discount rates θ1,θ2. Otherwise, their payoffs must be multiplied by
θ1,θ2 or their power, and so on, according to real discount situations.
Because the alternating offer–counteroffer game is a two-player
game with unlimited game time T=∞, which means there is no final
phase, themathematical induction cannot be directly applied to prove
the theorem. In fact any sub-game beginning from first-move Player 1
is equivalent to the game beginning from the first phase t=1;
therefore, the backward induction of alternating game with limited
game times can be directly employed to attain the perfect equilibrium
solution of sub-game.
If thefirstmover (Player1) canacquire themaximumvalueMat Phase
t≥3, themaximumshare (payoff) isP{x≤M}. To thefirstmover, the share
(payoff) P{x≤M} at Phase t is equivalent to the share (payoff) θ1P{x≤M}
at Phase t−1. The last mover (Player 2) knows that any offering share
(payoff) beingmore than θ1P{x≤M} at phase t−1 can be accepted by the
first mover (Player 1). The share (payoff) of last-move Player 2 cannot be
less than 1−θ1P{x≤M}, which is equivalent to θ2(1−θ1P{x≤M}) at
phase t−2. Player 1 knows that any offering share (payoff) x being less
than 1−θ2(1−θ1P{x≤M}) can be accepted by Player 2, so the Player 2's
payoff can attain θ2(1−θ1P{x≤M}). Since the sub-game beginning from
t−2 is equivalent to the sub-game beginning from t, the share (payoff) of
Player 1 at t must be equal to that of Player 1 at t−2. Thus, we have
following equation:
P x≤Mf g = 1−θ2 1−θ1P x≤Mf gð Þ
which makes it evident that P x≤Mf g = 1−θ21−θ1θ2.
Obviously, P{x≤M}=M due to the uniform distribution of ξ in the
closed interval [0, 1], so we can have M = 1−θ21−θ1θ2.
The above proof illustrates the maximum share offering of Player 1,
as well as his minimum share. Some corollaries are be deduced below.
1590 J. Yu, B. Xu / Economic Modelling 28 (2011) 1587–1594
Corollary 1. If the value ξ of target enterprise of M&A is of uniform
distribution in the closed interval [a,b](bNa≥0), the game equilibrium
price can be formulated as M = a + 1−θ21−θ1θ2 b−að Þ.
There are two players designated as Player 1 (first-move player)
and Player 2 (last-move player). Their strategy spaces can be
represented as S1={(a,M)|a≤M≤b} and S2={(M,b)|a≤M≤b},
where M denotes the maximum attainable share for Player 1. Their
payoff functions can be represented as P{x≤M} and 1−P{x≤M},
which are equal to P{x≥1−M} without regard to their corresponding
discount rates θ1,θ2. Otherwise, their payoffs must be multiplied by
θ1,θ2 or their power, and so on, according to real discount situations.
Based on Theorem 1, it is evident that P x≤Mf g = 1−θ21−θ1θ2; therefore,
∫
M
a
1
b−a dx =
1−θ2
1−θ1θ2
and M−a = 1−θ2
1−θ1θ2
b−að Þ, and we have M ¼
a +
1−θ2
1−θ1θ2
b−að Þ.
Corollary 2. If the value ξ of target enterprise of M&A, its density
function is f(x), which is of standard normal distribution N(0,1). Thus,
the equilibrium price Mmust satisfy ∫
M
−∞
f xð Þdx = 1−θ2
1−θ1θ2
, which means
Φ Mð Þ = 1−θ2
1−θ1θ2
and M = Φ−1
1−θ2
1−θ1θ2
� �
.
There are two players in M&A; one is merger enterprise and the
other is merged enterprise, which are represented as Player 1 (first-
move player) and Player 2 (last-move player), respectively, and their
strategy spaces can be represented as S1={(−∞,M)|M∈(−∞,∞)}
and S2={(M,+∞)|M∈(−∞,∞)} respectively, where M denotes the
maximum attainable share for Player 1. Their payoff functions can be
represented as P{x≤M} and 1−P{x≤M}, respectively, which is equal
to P{x≥1−M}, subject to x∈(−∞,∞) without regard to their
corresponding discount rates θ1,θ2; otherwise their payoffs must be
multiplied by θ1,θ2 or their power, and so on, according to real
discount situations.
Its proof process, which is similar to that of Corollary 1, can be
omitted; thus, we have Corollary 3.
Corollary 3. If the value variable ξ of target enterprise is distributed as
geometric Brownian motion with drifting feature, dx=αxdt+σxdz, the
equilibrium price M of target enterprise of M&A can be formulated as
M = M0 exp α−
1
2
σ2
� �
t + σ
ffiffi
t
p
Φ−1
1−θ2
1−θ1θ2
� ��
:
where x(0)=M0, the coefficients α and σ denote drifting rate and
variance rate, respectively.
Naturally, the expressions of the players, their strategy spaces
and payoff functions are the same with that of Corollary 2.
Apparently, if its density function f(x)(x∈R) is of normal distribution
N(μ,σ2), there will be ∫
M
−∞
f xð Þdx = 1−θ2
1−θ1θ2
, which can be normalized
as ∫
M−μ
σ
−∞
f yð Þdy = 1−θ2
1−θ1θ2
. Order y =
x−μ
σ
, we can have Φ
x−μ
σ
�
=
1−θ2
1−θ1θ2
; thus, the above formulation can be simply transformed to
x = μ + σΦ−1
1−θ2
1−θ1θ2
� �
.