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Applied Mathematical Sciences, Vol. 6, 2012, no. 110, 5487 - 5493
Goal Programming with Utility Function for
Funding Allocation of a University Library
Nasruddin Hassan* and Lim Lih Loon
School of Mathematical Sciences, Faculty of Science and Technology,
Universiti Kebangsaan Malaysia
43600 UKM Bangi, Selangor DE, Malaysia
[email protected]
Abstract
The funding of library is optimally utilized to achieve the need of users. We build
a goal programming model with utility functions to maximize the number of
reading materials bought and the utility for each field’s user for bought materials.
The model is then applied to a public university library. The goal programming
model illustrated an optimum solution for funding allocation with utility of each
field’s user of the library.
Keywords: Goal programming, Library fund, Utility function
1 Introduction
As a research university, Universiti Kebangsaan Malaysia (UKM) library
known as Perpustakaan Tun Seri Lanang (PTSL) is committed to be a source of
diversified information, from classical materials to digital reading materials. It
plays a vital role to ensure that UKM remains to be an institution of knowledge
relevant to current needs of education. As UKM aims to have a one to one ratio of
undergraduate to graduate intake by 2015 (Musa 2010), the library should not be
biased when allocating funds for academic areas. Thus, this gave rise to a
mathematic model that can give optimum and balanced solution for the allocation.
Due to limited funding but unlimited demand from library users, the library has to
properly apportioned its allocation. The total funding for the library has been
decreased from RM10905000 in 2011 to RM8395000 in 2012 (UKM 2011).Thus,
5488
N. Hassan and Lim Lih Loon
The importance of fair and unbiased allocation of funding for materials of
different academic fields is more obvious as resources are low.
The library may face multiple objectives. Goal programming is one technique that
can be used in such situations (Winston 2007) for solving multi criteria decision
making and multi objectives decision making problems by finding a set of
satisfying solutions (Chang et al. 2011). Hassan et al. (2010a, 2010b) and Hassan
and Tabar (2011) dealt with decision making of multiobjective resource allocation
problems. Hassan and Mohammad Basir (2009) and Hassan and Ayop (2012)
used goal programming for decision making in various applications.
Under some further mathematical assumptions, the preferences of the decision
maker can be modelled by the value or utility functions (Podinovski 2010). The
choice of a utility in portfolio selection in a given asset market is based on the
preferred degree of risk aversion, which is by nature subjective. In the financial
literature, except portfolio selection, a problem often includes consumption choice
as well (Yu et al. 2009). A multi-choice goal programming model with utility
functions is proposed so that the library not only can optimize the deviations of
variables from the goals, but also the utility of the decision being made.
2 Model Bulding
The two objectives of funding allocation are to:
i. maximize the use of funding to each field of knowledge.
ii. balance the purchase of materials with respect to the priority of the field of
knowledge.
The variables, constant, and constraints are listed below:
2.1 Decision variables
xi
= number of reading materials that should be bought for subject i
di
= under achievement of the ith goal
di +
= over achievement of the ith goal
e= under achievement of fund used from the total fund
+
e
= over achievement of fund used from the total fund
λi
= utility for the ith goal
fi
= dissatisfactory for ith goal
yi
= objective value of ith goal
Goal programming with utility function
5489
2.2 Coefficients and constants
average cost for reading materials of subject i
Ci =
T =
gmaxi
gmini
total funding available
= upper demand limit for subject i
= lower demand limit for subject i
2.3 Constraints
i.
Funding: Product of average cost for each reading material and its number
purchased must not exceed the total funding available. Also assume that the
amount of funding used, fund, should be at least half of the total funding
available, where dfund+ and dfund- are positive and negative deviations of the
product of average cost for each reading material and its number purchased.
m
∑ c x − dfund
i =1
i
+
i
1
T ≤ fund ≤ T ,
2
ii.
+ dfund − = fund
fund − e + + e − = T
Utility: Assume that if the number of reading materials purchased equal to
the greater of the amount purchased in the past two years, then utility is
maximized. Else utility is minimized. Thus gmini equals to the lesser
number purchased in that period for subject i while gmaxi equals to the
greater number.
g max n − d n+ + d n− = y n ,
g min n ≤ y n ≤ g max n
y n − g min n
λ n + f n− = 1
λn ≤
,
g max n − g min n
2.4 Objective function
The objective function is to minimize z, defined as the summation of all the
deviations from every goal.
m
min z = ∑ (d i+ + d i− + f i − ) + dfund + + dfund − + e + + e −
i =1
3 Application
The PTSL of UKM is the second largest library in South East Asia and
possesses collection of books running into millions of units. Based on the
library’s annual report of 2008, the total collection of books in is 657123 with RM
2250000 available for purchase of new materials. Nonetheless PTSL was
5490
N. Hassan and Lim Lih Loon
over-budgeted in the year 2008. PTSL has divided its collection of books into 32
areas. These include faculties, research centres, and other groupings as listed in
columns 1 and 2 of Table 1.
Table 1: Number of reading materials
i
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Faculty/Centre/Area
Engineering
Information Sci.&Tech
Env.Sci & Nat. Res.
Chem. Sci. & Food Tech
Mathematical Science
Applied Physics
Biosci.& Biotechnology
ANGKASA
IMEN
LESTARI
SEL FUEL
GENOME
SERI
IKON
IKMAS
History & Strategy
Education
Economy & Business
Language & Linguistic
Media & Comm.
Soc. Develop. & Env.
Psych & Human Dev.
Literature Lang. & Malay Culture
Islamic Collection
Media
Reference
S. E. Asia Collection
Document Collection
General Study
Thesis
Children Library
Co-Curriculum
TOTAL
Average
cost
407.680
278.877
393.296
579.785
341.712
530.188
428.849
339.112
649.163
405.931
437.141
628.910
442.013
97.418
334.650
260.687
249.829
263.697
246.165
343.251
211.871
341.520
82.165
90.752
400.103
517.509
79.025
165.057
202.820
294.517
15.374
343.479
Number in
year 2008
818
459
228
131
191
98
95
169
73
60
33
16
20
57
1
588
496
278
189
122
143
48
101
4,017
469
299
1,843
516
192
120
376
10
12256
Our mathematical model is
32
min z = ∑ ( d i+ + d i− + f i − ) + dfund + + dfund − + e + + e −
i =1
subject to
Number in
year 2007
897
1058
240
156
417
286
243
67
29
22
38
38
38
11
55
696
375
800
387
245
298
110
208
233
584
153
1399
401
57
268
180
58
10047
Optimum
number xi
818
459
228
131
191
98
95
67
29
22
33
16
20
27
1
588
375
278
189
122
145
48
208
4017
469
153
1843
437
57
120
376
10
8323
Goal programming with utility function
32
∑c
i =1
i
5491
xi − dfund + + dfund − = fund
1125000 ≤ fund ≤ 2250000 ,
fund − e + + e − = 2250000
g max n − d n+ + d n− = y n ,
g min n ≤ y n ≤ g max n
λn ≤
y n − g min n
,
g max n − g min n
λ n + f n− = 1
n = {1,2,3,…,32}
4 Result and Discussion
LINGO is used to solve this model. The optimal number of reading materials
to be bought is displayed in the last column of Table 1. Table 2 lists the values of
utility function, overachievement and underachievement variables.
Table 2: Deviational variables and utility values
i
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
Faculty/Centre/Area
Engineering
Information Science and Technology
Environmental Science & Natural Resources
Chemical Science & Food Technology
Mathematical Science
Applied Physics
Bioscience & Biotechnology
ANGKASA
IMEN
LESTARI
SEL FUEL
GENOME
SERI
IKON
IKMAS
Political History & Strategy
Education
Economy & Business
Language & Linguistic
Media & Communication
Development Social & Environment
Psychology & Human Development
Literature Language & Malay Culture
Islamic Collection
Media
Reference
South East Asia Collection
Document Collection
General Study
Thesis
Children Library
Co-Curriculum
d+
70
599
12
25
226
188
148
102
44
38
5
22
18
0
54
108
121
532
198
123
153
62
0
0
115
146
0
79
135
148
0
48
d0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Utility
0
0
0
0
0
0
0
0
0
0
0
0
0
1
0
0
0
0
0
0
0.013
0
1
1
0
0
1
0.313
0
0
1
0
5492
N. Hassan and Lim Lih Loon
dfund+ = 0.000000, dfund- = 0.5760000
e+
= 0.000000, e- = 0.000000
fund
= 2250000
It is found that fund = RM 2250000, implying that the funding has been fully
utilized. The dfund- small value of 0.576 shows that there is only RM 0.576 left.
Values of 0 for e+ and e- mean that the total of funding used equals to the total
funding available. d+ is the reduction of the number of reading materials bought
from the greater number of the past two years, and vice versa for d-. The values of
d 2+ for Information Science and Technology and d18+ for Economy and Business
are greater than the others. These might probably be due to the big difference
between the number of reading materials bought in the past two years. If too many
books were bought last year, the need for new books will be lower for the present
year.
5 Conclusion
Goal programming with utility functions to overcome the funding allocation
problem in purchasing reading materials has been successfully applied to a
university library. The utility value approach will help libraries make better
decisions in optimizing funding allocation in order to maximize utility with
limited resources such as this library funding allocation problem.
Acknowledgement
We are indebted to Universiti Kebangsaan Malaysia for funding this research
under the grant UKM-GUP-2011-159.
References
[1] C.T. Chang, 2011. Multi-choice goal programming with utility functions.
European Journal of Operational Research, 215: 439-445.
[2] N. Hassan and Z. Ayop, 2012. A goal programming approach for food
product distribution of small and medium enterprises. Advances in
Environmental Biology, 6(2): 510-513.
[3] N. Hassan and S.B. Mohammad Basir, 2009. Goal programming model for
scheduling political campaign visits in Kabupaten Kampar, Riau, Indonesia.
Journal of Quality Measurement and Analysis, 5(2): 99-107 (in Malay).
[4] N. Hassan and M.M. Tabar, 2012.The relationship of multiple objectives
linear programming and data envelopment analysis. Australian Journal of
Basic and Applied Sciences, 5(11): 1711-1714.
Goal programming with utility function
5493
[5] N. Hassan, M.M. Tabar and P. Shabanzade, 2010a. A ranking model of data
envelopment analysis as a centralized multi objective resource allocation
problem tool. Australian Journal of Basic and Applied Sciences, 4(10):
5306-5313.
[6] N. Hassan, M.M. Tabar and P. Shabanzade, 2010b. Resolving multi
objectives resource allocation problem based on inputs and outputs using
data envelopment analysis method. Australian Journal of Basic and Applied
Sciences, 4(10): 5320-5325.
[7] S.Musa, 2010. UKM aims at having a fifty-fifty ratio of undergraduate to
graduate students intake by 2015. UKM News Portal. http://www.ukm.my/
news/index.php/en/extras/377-ukm-aims-at-having-a-fifty-fifty-ratio-ofunder graduate -to-graduate-students-intake-by-2015.html [Accessed 5 May
2012]
[8] V.V. Podinovski, 2010. Set choice problems with incomplete information
about the preferences of the decision maker. European Journal of Operational
Research, 207: 371–379.
[9] UKM. 2012. Statistik perpustakaan UKM 2011. http://www.ukm.my/library/
download/ STATISTIK RINGKAS PERPUSTAKAAN 2011.pdf [Accessed
5 May 2012]
[10] W. L. Winston, Operations Research: Applications and Algorithms,
Thomson Learning, New York, 2007.
[11] B.W.T. Yu, W.K. Pang, M.D. Troutt and S.H. Hou, 2009. Objective
comparisons of the optimal portfolios corresponding to different utility
functions. European Journal of Operational Research, 199: 604–610.
Received: May, 2012