INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 5, ISSUE 06, JUNE 2016
ISSN 2277-8616
Using Computer Techniques To Predict OPEC Oil
Prices For Period 2000 To 2015 By Time-Series
Methods
Mohammad Esmail Ahmad, Ali Jalal Hussian, Monem A. Mohammed
Abstract: The instability in the world (and OPEC) oil process results from many factors through a long time. The problems can be summarized as that
the oil exports don’t constitute a large share of N.I. only, but it also makes up most of the saving of the oil states. The oil prices affect their market
through the interaction of supply and demand forces of oil. The research hypothesis states that the movement of oil prices caused shocks, crises, and
economic problems. These shocks happen due to changes in oil prices need to make a prediction within the framework of economic planning in a short
run period in order to avoid shocks through using computer techniques by time series models.
Keywords: Fluctuations in oil prices, prediction, Time-Series Forecasting, computer techniques, Holt Winter, Exponential Smoothing, Analyzing
Techniques, Stationary, information technology.
————————————————————
INTRODUCTION
Oil is important for the entire world, so it doesn’t play as
good as a vital role in economic life as the oil play in
underdeveloped countries. Clearly, oil is the economic life
for countries that have oil, such as Venezuela, Middle East,
Arabian Gulf and North Africa. Oil exports do not constitute
a large share of national income only. Also, it makes up
most of the saving of the oil states. Therefore, Oil is the
primary Source of capital needed for economic
development. Also, Oil as fuel is indispensable for modern
agriculture and industry sector in addition to being a major
fuel meets needs to secure the necessary consumption. So
we can summarize importance of Oil and the role in the
following properties: [2]
1. It could be considered as a key driver of the global
economy.
2. It could be considered as a major or source of energy
within the global economy.
3. It could be considered as more strategic goods traded.
4. It significantly contributes to the G.D.P of underdeveloped countries.
5. It significantly contributes to the government revenues
of underdeveloped countries.
6. It significantly contributes to the balance of payments of
underdeveloped countries.
7. It can contribute to creating interdependence between
industry, agriculture, and services.
_____________________
Assis. Lect. Mohammad Esmail Ahmad is a lecturer at
University of Sulaimani, M.Sc. in the field of Computer
Science, E-mail: mohammad.ahmad@univsul.edu.iq
Assis. Prof. Dr. Ali Jalal Hussian is a lecturer at
University of Sulaimani, PhD in the field of Economics,
E-mail: alijalal4@yahoo.com
Prof. Dr. Monem A. Mohammed is a lecturer at
University of Sulaimani, PhD in the field of Statistics,
E-mail: monem_aziz2003@yahoo.com
1.1 The Research Problem:
Can be summarized as that oil prices affect their market
through the interaction of supply and demand forces of oil
according to tracker for evolution of oil prices to historic
periods of times characterized by large and volatile swings,
sometimes up and down movement due to upward and
downward economic activity for global economy between
stagnation and growth, which is reflects positively or
negatively impact on prices.
1.2 The Research Hypothesis:
The research hypothesis states:
―The movement of oil prices (downward and upward)
caused shocks, crises, and economic problems.‖ These
shocks happen due to changes in oil prices need to make
forecasts within the framework of economic planning in a
short run period in order to avoid shocks.
1.3 The Research Importance:
Time-Series is one of the most important predictive
methods in short-run term because of its importance in the
field of economic planning in general and in particular of
prices. The researchers resorted to use computer
techniques (Microsoft Excel, Statistical Analysis Software
Package-SPSS) and forecasting method (Time-series), in
addition to the analytical method for analyzing the reality of
oil prices in the period of research.
1. THEORETICAL FRAMEWORK
The importance of forecasting in economics field had been
expanded due to increasing of economic problems, it make
adoption of economic planning to avoid these problems. It
came when economic fluctuation happened to avoid losses
in potential resources. The forecasting conducts demands
and prices to make the possibility to apply economic
policies in order to affect demands and prices in different
levels. So predictability needs to increase using economic
indicators such as price elasticity to make policies in order
to overcome problems. The evolution in the field of
computer and information systems generate accuracy of
predictions. [11]
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2.1 The Stages of Forecasting:
The prediction process doing through following stages: [1]
1. Building model: It makes through building model.
2. Estimating model: It makes that building model to find
the data for economic variables in the models, and
choice the relevance method for estimating according
to computer requirement and prediction specification.
3. Evaluate model: It makes building model to analyze the
economic indicators from where the sign and value of
estimated coefficient within the framework of economic
theory.
4. Preparing forecasts through using data accurate
predictions.
2.2 Forecasting Methods:
There are different methods and techniques for forecasting
according to the different level of complexity, the theoretical
foundations, and Statistical requirement. So the methods
used vary about the accuracy of forecasts. The major
technique for forecasting is time-series. It’s interested in
analyzing the time – trend of the economic phenomenon to
be predictable. Forecasting is very important for prediction
of the feature events .Science and computer technology
together has made significant advances over the past
several years and using those advanced technologies and
few past patterns, it grows the ability to predict the future
.Feature prediction is a process of choosing the best subset
of the features available from the selected input data .The
best subset contains the minimum number of dimensions
that contribute more accuracy. [12]
2.3 Time Series Model:
Some models such as the Oil pricing model and the
arbitrage pricing model described as time series data.
However, there is much to be said for analyzing data
without imposing constraints that are implied by a theory.
The aim of time series analysis is to find the most
appropriate statistical model for the data and to use this
model for prediction. In this way, the variables are allowed
to speak for themselves. Without the confine of economic
theories. In Oil markets, the modelling procedures for return
data and for price data are different to understand why. On
needs to draw the basic distinction between stationary and
non-stationary time series Daily and Monthly return data on
most Oil markets are generated by stationary processes
and consequently returns. In fact, they are often rapidly
mean-reverting since there is very little autocorrelation in
many oil market returns. The statistical concepts and
methods that apply to return data do not apply to price data.
For example volatility and correlation are concepts that only
apply to stationary processes it makes no sense to try to
estimate volatility or correlation on price data. Daily (log)
price data are commonly assumed to be generated by a
non-stationary stochastic process. [7]
2.4 Concept of Information Technology:
Human started from ancient to think about how to arrange
their works with methods that guarantee them the best use
of time and effort, with the appearance of computerized
machines which have had a significant role in the conduct
of business, and gradually the computer programmer
emerged, causing a growth in all aspects of scientific,
technical and administrative life as it began this
ISSN 2277-8616
renaissance leading investment into the world of
technology.The term Information Technology (IT) has
appeared in the early seventies with the emergence of
electronic computer on a commercial scale, and the
concept of information technology means all the things that
include computers of various types and data processing in
all its forms and information and all the centers and
functions related to technology and services in
organizations and institutions, as well as software and
programming packages that are used in doing business,
jobs, and product marketing. [8] ―Information Technology
(IT) may be defined as the technology that is used to
acquire, store, organize, process, and disseminate
processed data which can be used in specified applications.
Information is processed data that improves our knowledge,
enabling us to take decisions and initiate actions‖. [13]
2.5 Importance of Information Technology:
The Importance of (IT) can be summarized as the following:
[16]
1. Information Technology works on major changes in the
entire organization, as in their products, markets, and
gives employees the flexibility to work anywhere either
in their organizations or at home.
2. Provide more information to assist controlling the
decisions taken by their users.
3. Help to create new communication channels, therefore,
it increases flowing, processing and exchanging
information and develop modern management
methods.
4. Works to improve and increase business opportunities
between organizations, and between organizations and
the government, which led to a wider spread of
information.
5. Helps detecting deviations to prevent the aggravation
and work on a specialized processor.
6. Helps to improve customer service by meeting their
demands via terminals.
7. Improves the quality of work through the adoption of
new technological methods and thus achieve high
accuracy, shorten the time, reduce costs and risk of
humanitarian unprepared interpretation of the
information and data.
8. Contributes to reduce the volume of the costs which
allocated to provide factors of production.
9. Improves the process of collecting, processing, storing,
retrieving, updating and reducing cost of data as it
would reduce the cost of administrative work.
10. Creating the most effective managerial tools to apply
what can be applied in the normal conditions and
leading the renewal process.
2.6 Component of Information Technology:
Information technology consists of the following five parts,
as shown in (Figure 1): [10]
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the next period. Mathematically, a moving average forecast
of order k is as follows: [5]
𝐹
=
∑
Where;
2.
3.
4.
5.
𝐹
= 𝑓𝑜𝑟𝑒𝑐𝑎𝑠𝑡 𝑜𝑓 𝑡𝑒 𝑡𝑖𝑚𝑒𝑠 𝑠𝑒𝑟𝑖𝑒𝑠 𝑓𝑜𝑟 𝑝𝑒𝑟𝑖𝑜𝑑 𝑡
+1
𝑌 = 𝑎𝑐𝑡𝑢𝑎𝑙 𝑣𝑎𝑙𝑢𝑒 𝑜𝑓 𝑡𝑒 𝑡𝑖𝑚𝑒 𝑠𝑒𝑖𝑟𝑒𝑠 𝑖𝑛 𝑝𝑒𝑟𝑖𝑜𝑑 𝑡
The term moving is used because every time a new
observation becomes available for the time series, it
replaces the oldest observation in the equation and a new
average is computed. As a result, the average will change,
or move, as new observations become available.
Fig. 1: Component of Information Technology
1.
(1)
=
People: The most important part as they make endusers more productive.
Procedure: Refer to rules or guidelines people follow
when using software, hardware, and data. Documented
in manuals written by computer specialists and
provided by software/hardware manufacturers of the
product.
Software: It is the term for programs or sets of
computer instructions written in a special computer
language that enables a computer to accomplish a
given task. It consists of step-by-step instructions,
which the computer can use to convert data into
information.
Hardware: Refers to physical, touchable pieces or
equipment.
Data: Raw, unprocessed facts including text, numbers,
images and sounds. Data describes something that is
stored electronically in a file.
2.7 Statistics by MS-Excel:
There are a number of commonly used, powerful tools for
carrying out statistical analyses. The most popular of these
are Statistical Package for the Social Sciences (SPSS),
Statistical Analysis System (SAS), Stata, Minitab and R.
Many researchers choose to apply Excel as their major
analysis tool or as a complementary to each other tools for
any of the following reasons: [19]
1. It is widely available and so many researchers already
know how to use it.
2. It is not necessary to pay the cost of another tool (as
some of the popular tools are quite expensive).
3. It is not necessary to learn new methods of manipulating
data and drawing graphs.
4. It provides numerous built-in statistical functions and
data analysis tools.
5. It is much easier to see what is going on since, unlike
the more commonly used statistical analysis tools, very
little is hidden from the user.
6. It provides the user with a lot of control and flexibility.
2.8. Techniques Used:
2.8.1 Moving Average:
The moving averages method uses the average of the most
recent k data values in the time series as the forecast for
2.8.2 Exponential Smoothing:
Exponential smoothing uses a weighted average of past
time series values as a forecast; it is a special case of the
weighted moving averages method in which we select only
one weight—the weight for the most recent observation.
The weights for the other data values are computed
automatically and become smaller as the observations
move farther into the past. The exponential smoothing
equation follows: [6]
𝐹
Where;
= 𝛼𝑌 + 1 − 𝛼 𝐹
(2)
𝐹 = 𝑓𝑜𝑟𝑒𝑐𝑎𝑠𝑡 𝑜𝑓 𝑡𝑒 𝑡𝑖𝑚𝑒 𝑠𝑒𝑟𝑖𝑒𝑠 𝑓𝑜𝑟 𝑝𝑒𝑟𝑖𝑜𝑑 𝑡 + 1
𝑌 = 𝑎𝑐𝑡𝑢𝑎𝑙 𝑣𝑎𝑙𝑢𝑒 𝑜𝑓 𝑡𝑒 𝑡𝑖𝑚𝑒 𝑠𝑒𝑟𝑖𝑒𝑠 𝑖𝑛 𝑝𝑒𝑟𝑖𝑜𝑑 𝑡
𝐹 = 𝑓𝑜𝑟𝑒𝑐𝑎𝑠𝑡 𝑜𝑓 𝑡𝑒 𝑡𝑖𝑚𝑒 𝑠𝑒𝑟𝑖𝑒𝑠 𝑓𝑜𝑟 𝑝𝑒𝑟𝑖𝑜𝑑 𝑡
𝛼 = 𝑠𝑚𝑜𝑜𝑡𝑖𝑛𝑔 𝑐𝑜𝑛𝑠𝑡𝑎𝑛𝑡 0 ≤ 𝛼 ≤ 1
2.8.3 Double Exponential Smoothing:
Charles Holt developed a version of exponential smoothing
that can be used to forecast a time series with a linear
trend. The smoothing constant α to ―smooth out‖ the
randomness or irregular fluctuations in a time series; and,
forecasts for time period t + 1 are obtained using the
equation: [6]
𝐹
=𝐿 +𝐵 𝐾 +𝜖
(3)
Forecasts for Holt’s linear exponential smoothing method
are obtained using two smoothing constants, α and _, and
three equations:
𝐿̂ = 𝛼𝑌 + 1 − 𝛼 𝐿̂
+ 𝐵̂
𝑏̂ = 𝛽(𝐿̂ − 𝐿̂ ) + 1 − 𝛽 𝑏̂
𝐹 = 𝐿̂ + 𝑏̂ 𝑘
(K=1,2,…,n)
(4)
(5)
(6)
Where;
𝐿 = 𝑒𝑠𝑡𝑖𝑚𝑎𝑡𝑒 𝑜𝑓 𝑡𝑒 𝑙𝑒𝑣𝑒𝑙 𝑜𝑓 𝑡𝑒 𝑡𝑖𝑚𝑒 𝑠𝑒𝑟𝑖𝑒𝑠 𝑖𝑛 𝑝𝑒𝑟𝑖𝑜𝑑 𝑡
𝑏 = 𝑒𝑠𝑡𝑖𝑚𝑎𝑡𝑒 𝑜𝑓 𝑡𝑒 𝑠𝑙𝑜𝑝𝑒 𝑜𝑓 𝑡𝑒 𝑡𝑖𝑚𝑒 𝑠𝑒𝑟𝑖𝑒𝑠 𝑖𝑛 𝑝𝑒𝑟𝑖𝑜𝑑 𝑡
𝛼 = 𝑠𝑚𝑜𝑜𝑡𝑖𝑛𝑔 𝑐𝑜𝑛𝑠𝑡𝑎𝑛𝑡 𝑓𝑜𝑟 𝑡𝑒 𝑙𝑒𝑣𝑒𝑙 𝑜𝑓 𝑡𝑒 𝑡𝑖𝑚𝑒 𝑠𝑒𝑟𝑖𝑒𝑠
𝛽 = 𝑠𝑚𝑜𝑜𝑡𝑖𝑛𝑔 𝑐𝑜𝑛𝑠𝑡𝑎𝑛𝑡 𝑓𝑜𝑟 𝑡𝑒 𝑠𝑙𝑜𝑝𝑒 𝑜𝑓 𝑡𝑒 𝑡𝑖𝑚𝑒 𝑠𝑒𝑟𝑖𝑒𝑠
𝐹 = 𝑓𝑜𝑟𝑒𝑐𝑎𝑠𝑡 𝑓𝑜𝑟 𝑘 𝑝𝑒𝑟𝑖𝑜𝑑𝑠 𝑎𝑒𝑎𝑑
𝑘 = 𝑡𝑒 𝑛𝑢𝑚𝑏𝑒𝑟 𝑜𝑓 𝑝𝑒𝑟𝑖𝑜𝑑𝑠 𝑎𝑒𝑎𝑑 𝑡𝑜 𝑏𝑒 𝑓𝑜𝑟𝑒𝑐𝑎𝑠𝑡
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2.8.4 Holt-Winters: (Triple exponential smoothing):
Holt (1957) and Winters (1960) extended Holt’s method to
capture seasonality. The Holt-Winters seasonal method
comprises the forecast equation and three smoothing
equations—one for the level ℓ , one for trend 𝑏 , and one
for the seasonal component denoted by 𝑆 , with smoothing
parameters 𝛼, 𝛽 and 𝛾. We use 𝑚 to denote the period of
the seasonality, i.e., the number of seasons in a year. There
are two variations to this method that differ in the nature of
the seasonal component. The additive method is preferred
when the seasonal variations are roughly constant through
the series, while the multiplicative method is preferred when
the seasonal variations are changing proportionally to the
level of the series. With the additive method, the seasonal
component is expressed in absolute terms in the scale of
the observed series, and in the level equation, the series is
seasonally adjusted by subtracting the seasonal
component. Within each year, the seasonal component will
add up to approximately zero. With the multiplicative
method, the seasonal component is expressed in relative
terms (percentages) and the series is seasonally adjusted
by dividing through by the seasonal component. Within
each year, the seasonal component will sum up to
approximately. [22]
It contains three equations: [11]
𝑆 =
+ 1 − 𝑎 {𝑆
+ 𝑏̂
for t= (1,2,..,n) and L=12
}
(7)
Time-Trend Preliminary Equation
(9)
+ 1−𝛽 𝑖
From the three equations above, we get the following
Preliminary Exponential Tripartitly equation:
= {𝑆 + 𝑏̂ 𝑚 }𝐼
(10)
for m=(1,2,…)
2.9 Stationary Time Series:
Let, we have stationary time series {𝑍 ; 𝑡 = 0 ± ,1 ± 2, … },
then, we have the following ARMA (P, q) process: [18]
𝑍 = ∅𝑍 + ∅ 𝑍
− . . . −𝜃 𝛼
Where 𝑍 = 𝑍̃ – μ
+
Then, ARMA (1, 1) distributed Gaussian or normal
distribution.
By using (𝐵) operator we get:
𝑍 {1 − ∅ 𝐵 − ∅ 𝐵 −. . . −∅ 𝐵 }
= {1 − 𝜃 𝐵 − 𝜃 𝐵 −
∴𝑍 =
{𝑍 =
{
{
∅
∅
𝑎}
... ∅
Where
}
}
𝑎
−𝜃 𝐵 }𝑎
(12)
are
𝛩 𝐵 𝑎𝑛𝑑 𝛷 𝐵
the
polynomial functions of order (q) and (p) in (B) respectively.
𝑜𝑟 { 𝑍 = 𝜓 𝐵 𝑎 } where:
1
=𝜓 𝐵 +𝜓 𝐵 +𝜓 𝐵 +𝜓 𝐵 +
𝜓 𝐵 =
(13)
=∑
𝜓 𝐵 =
𝜓 𝐵 ,𝜓 = 1
,𝜓 =
𝜓 = 1, 𝜓 , 𝜓 , ψ , … are the weights.
-
+∅ 𝑍
+
+
With (k = 0, 1, 2 ...), and by using covariance form with lag
(k) is (𝑅 ) then, we have:
Seasonal Preliminary Equation
𝜃𝛼
Covariance of (𝜕 , 𝜕 ± ) = 0, for all k ≠ 0.
Let the auto correlation with lag (k) is:
𝐸 𝑍 .𝑍
= ∅ 𝐸 𝑍 .𝑍
+∅ 𝐸 𝑍 .𝑍
∅ 𝐸 𝑍 .𝑍
+ 𝐸 𝑎 .𝑍
− 𝜃 𝐸 𝑎 .𝑍
−
𝜃 𝐸 𝑎 .𝑍
− −𝜃 𝐸 𝑎 .𝑍
(15)
for t= (1,2,..,n)
𝑍
and
By using Yule – walker equations we get the (ACF) as
follows:
for t=(1,2,..,n) and L= 4
𝐼 =
Variance of (𝜕 )= E (𝜕 )2 =𝜎
For St. Time series (𝑍 , (t = 1, 2, 3… n) [17]
𝑍 = ∅ 𝑍 +∅ 𝑍
+ ....+ ∅ 𝑍
+𝑎 - 𝜃 𝑎 - 𝜃 𝑎
... - 𝜃 𝑎
(14)
(8)
+ 1−𝛾 𝑏
For each (t), (μ) is the mean of time series and {𝑎 }is a
purely random error (white noise) distributed Gaussian with
E (𝜕 )= 0,
2.10 Autocorrelation Function of the Autoregressive
Moving Average Model:
General Preliminary Exponential Equation
𝑏 =𝛾 𝑠 −𝑠
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+𝛼 −𝜃 𝛼
𝑅 = ∅ 𝑅
+∅ 𝑅
+ +∅ 𝑅
+ 𝐸 𝑎 .𝑍
−
𝜃 𝐸 𝑎 .𝑍
− 𝜃 𝐸 𝑎 .𝑍
− − 𝜃 𝐸 𝑎 .𝑍
(16)
Now, 𝐸 𝑎 . 𝑍
= 0 𝑓𝑜𝑟 𝑘 > 𝑡 .
So, 𝑅 = ∅ 𝑅
+∅ 𝑅
+ +∅ 𝑅
, with (k ≥
q+1)
Let the (ACF) is: 𝜌 =
, (k = 0 ± ,1 ± 2, … .
Then, 𝜌 = ∅ 𝜌
q+1)
∴ 𝜌 =
−
(11)
∑
∑
+∅ 𝜌
+
+∅ 𝜌
, (k = 0 ± ,1 ± 2, …
with (k ≥
(17)
For example: for AR(1) process we have:
𝜓 = ∅ , with |∅ | < 1
By substituting in AR(1) process we get the ACF of AR(1)
as follows:
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∑
=
∑
=0 ± ,1 ± 2, … .
∑
∑
∅ ∅
∅
=
∅
∅
∅
= ∅ ,
With
(k
2.11 The Partial Autocorrelation Function:
The autocorrelation function of an MA series exhibits
different behavior from that of AR and general ARMA series.
The (ACF) of an (MA) series cuts of sharply whereas those
for (AR) and (ARMA) series exhibit exponential decay (with
possible Sinusoidal behavior superimposed). This makes it
possible to identify an (ARMA) series as being a purely
(MA) one just by plotting its autocorrelation function. The
partial autocorrelation function provides a similar way of
identifying a series as a purely (AR) one. Given a stretch of
time series values:
𝑍
,𝑍
,…,𝑍
+
+∅ 𝑍 + 𝑎
Denoted the (i) regression parameters and (𝑎 ) is a
normal error term, uncorrelated with 𝑋
for 𝑗 ≥ 1 But
the additional correlation between (𝑍 ) and (𝑍 ) after their
mutual linear dependency on the intervening variables
{𝑍 , 𝑍 , … , 𝑍
, } has been removed which is usually
followed by a conditional autocorrelation as:
∅
= Cor Z , Z
|Z
So the results shown in the bellow table:
Table 1: Time series model indicators:
,𝑍 ,…
The partial correlation of (𝑍 ) and (𝑍 ) is the correlation
between these random variables which is not conveyed
through the intervening values. If the (𝑍 ) values are
normally distributed, the partial autocorrelation between (𝑍 )
and (𝑍 ) can be defined as the partial autocorrelation
function can be thought of as the partial regression
coefficition ∅ in the representation: [14]
𝑍 =∅ 𝑍
+∅ 𝑍
Where: ∅ ; 𝑖 = 1,2, … , 𝑘
3.1 Descriptive model:
The researchers used Microsoft Excel to estimate the
following time series methods forecasting OPEC oil prices
for period (2000-2015):
1. Time series moving average smoothing.
2. Time series exponential smoothing.
3. Time series Double exponential smoothing.
4. Time series Holt winter-(additive) model.
5. Time series Holt winter-(Multiplicative) model.
6. Time series Holt winter-(No Trend) model.
∅
,
∅
,
And
=
= ∅ −∅
∑
,
∅
,
, (j=1, 2, ... k)
3. PRACTICAL FRAMEWORK
b
55.030
c
56.943
d
55.357
e
57.455
f
54.847
120
100
80
60
40
20
0
Jan-00
(18)
∅
66.444
140
,…,Z
∅
M.S.E.
a
Time Plot of Actual Vs. Forecast
And after solving the equations of general formula to
determining the initial estimates for parameters (∅ ) and
(∅ ) under the stationary condition we have: [11]
∑
Model
The above table shows that the mean squares error
(M.S.E) indicates that the minimum value is (54.847) in
spite of (Holt winter no-trend), but this value is still high
level. We can show, in (Figure 2), the time plot of actual Vs.
Forecast data as bellow.
US $/Barrel
𝜌 =
ISSN 2277-8616
Forecast
Actual
Sep-02
Jun-05 Mar-08 Dec-10 Sep-13
Jun-16
months
Fig. 2: represent the actual price oil Vs. Forecast price oil
(19)
In our research, we gather data of Oil basket price for the
period of Jan 2000 to Feb 2016. We use different methods
to predict the price for next 6 months with the help of
computer system using Microsoft Excel and SPSS
technology, then carried out a comparative study of nine
different forecasting technique. The data set is used, was
collected from the OPEC & OAPEC organization. [21]
We conclude that the model above (f) suffer from
Autocorrelation
problem,
because
the
estimators
characterized by non-stationary estimators.
3.2 Box and Jenkins models analysis:
To analysis the data of (Oil-Price) by using (Box and
Jenkins) models to show the problem of the data in time
series, we can applied the following steps in order to
overcome the problem by using SPSS system:
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INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 5, ISSUE 06, JUNE 2016
Step (1): The actual Sequence Series plot:
ISSN 2277-8616
Step (4): The ACF and PACF of the first difference of
sequence series Plots:
Fig 3: represent the actual Sequence Series plot
Step (2): The (ACF and PACF) of actual sequence series
Plots:
Fig. 7: represent the (ACF and PACF) of the first difference
of sequence series plot
Step (5): From analysis all (Box and Jenkins) models, we
consider the following (ARIMA) Models to forecasting the
(Oil –Prices) in year (2016):
Table 2: Represented the (ARIMA) models:
Fig. 4: represent the (ACF and PACF) of actual sequence
series plot.
Models
R-Square
R MSE
BIC
ARIMA(0,1,2)
0.949
7.350
4.072
ARIMA(2,1,2)
0.949
7.347
4.126
ARIMA(2,1,0)
0.949
7.368
4.077
ARIMA(2,1,1)
0.949
7.386
4.109
From above table we show that the best model is ARIMA (0,
1, 2) has the less values of (R MSE = 7.350, Bic = 4.072)
and has the greatest (R- square = 0.949).
Table 3: Represent Forecasting (ARIMA) models in year
(2016):
Fig. 5: represent the first difference of actual sequence
series plot
Step (3): Take the first difference for Sequence series plot
as follows:
Models
193
194
195
196
197
198
199
200
ARIMA
(0,1,2)
ARIMA
(2,1,2)
ARIMA
(2,1,0)
ARIMA
(2,1,1)
33.
27
32.
33
33.
29
33.
29
31.
87
34.
01
32.
20
32.
14
31.
90
35.
43
32.
21
32.
06
31.
94
34.
28
32.
06
31.
89
31.
97
33.
04
32.
10
31.
90
32.
00
33.
91
32.
10
31.
90
32.
04
35.
12
32.
13
31.
92
32.
07
34.
62
32.
16
31.
95
From above table we show the range of predicted oil prices
for (6) months, approximately between 31 $ to 33 $ for
barrel.
Step (6): We can find the estimate the parameters of
(ARIMA (0, 1, 2) Model as follows:
Fig. 6: represent the first difference of actual sequence
series plot
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INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 5, ISSUE 06, JUNE 2016
Table 4e: Forecast:
t
Sig.
.605
.054
.957
Difference
1
.748
.456
Lag 1
.054
.072
Lag 2
-.193
.072 -2.680
.008
Table 4b: Model Statistics:
ztModel
0
.036
Rsquare
d
Model
Number of
Predictors
Model Fit statistics
Stationa
ry
Rsquared
MA
E
Ljung-Box Q(18)
Normalize
Statisti
d
DF Sig.
cs
BIC
4.31
0
.949
Model
SE
.033
4.072
193
194
195
196
197
198
199
zt-Model_1
U
Forec
C
ast
L
Estimate
Constant
200
33.27 31.87 31.90 31.94 31.97 32.00 32.04
32.07
47.77 51.83 57.81 62.66 66.85 70.60 74.01
77.18
18.77 11.91
-13.04
L
C
L
No
Transformatio
n
Zt
zt-Model_1
Table 4a: ARIMA model Parameters:
MA
ISSN 2277-8616
6.00
1.21
-2.91
-6.59
-9.94
For each model, forecasts start after the last non-missing in
the range of the requested estimation period.
10.467 16 .841
Mod
el
Table 4c-1: Residual ACF:
1
2
3
4
ztModel_1
ACF .003 -.006 .017
SE
.072
.072
5
6
-.031 -.046
.040
.072 .072 .072 .073
Fig. 8: Time plot of actual VS Forecast. ARIMA estimated
model
ztModel
_1
Mo
del
Table 4c-2: Residual ACF:
7
8
9
10
11
12
ACF -.066 -.116 -.058 .073 .097
SE
.073
.073
From the figure above, we show that the actual values VS
predicted values are very approach, which means the
estimators are best and stationary.
.074 .074 .075
.040
4. CONCLUSIONS
.075
ztMod
el_1
Mod
el
Table 4d-1: Residual PACF:
1
2
3
4
5
6
PACF
.003
-.006
.017
-.040
-.031
-.047
SE
.072
.072
.072
.072
.072
.072
ztModel
_1
Model
Table 4d-2: Residual PACF:
7
8
9
10
11
12
PACF
-.065
-.118
-.062
.067
.095
.031
SE
.072
.072
.072
.072
.072
.072
The researcher reaches to the following major conclusion:
1. The oil price was fluctuates through long-term period.
And it causes shocks, crises and many economic
problems for OPEC countries.
2. The necessity of oil price in economies of oil generates
to make prediction for oil prices in order to subjugate
that in planning to avoid the economic problems.
3. The famous and the best method or forecasting is time
series, that it plays important role for this purpose.
4. The estimated model, (Moving average, exponential
smoothing, and Holt winter) suffer from Autocorrelation
problem, so we must to overcome this problem.
5. By using (Box and Jenkins) models we proved that
ARIMA (0,1,2) is the best estimated model which
become greater stationary and has less Mean squared
Error (M.S.E).
6. The range predicted (oil –prices) of OPEC for next six
months approximately between 31 $ to 33 $ for barrel.
7. Any change upper or down the range above is affected
by exogenous variables.
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INTERNATIONAL JOURNAL OF SCIENTIFIC & TECHNOLOGY RESEARCH VOLUME 5, ISSUE 06, JUNE 2016
5. REFERENCES
5.1 Books and Researches:
[1] Abraham, B. and LEDOTER, J. 1983, ―Statistical methods for
forecasting‖, Johan Wiley, NEWYORK.
[2] Al-HEETY, A., 2000, ―Economies of petrol, Mosel University
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[3] Al-MAZINI, E., 2013, ―The factors affect the fluctuations in
world oil prices (2000-2010)‖, Al-AZHAR University Journal –
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[4] Anderson, T.W, 1971, ―The statistical analysis of Time series,
John Wiley, NEWYORK.
[5] Anderson, D., Sweeney, D., 2015, ―Modern Business statistic
with Microsoft Excel‖, CENGAGE learning Pub., NEWYORK.
ISSN 2277-8616
[17] TSAY, R.S., and TIAO, G.C., 1948, ―Consistent estimates
Autoregressive Parameters and extended sample
Autocorrelation function for stationary and non-stationary
ARIMA models‖, JASA, Vol.79, No.384.
[18] WEI, w.w.s.1990, ―Time series methods‖.
[19] ZAIONTS, C., 2015, ―Statistics using EXCIL Succinctly, Sync
fusion Inc.
5.2 Electronic Websites:
[20] www.marketoracle.co.uk
[21] www.opec.org
[22] www.otexts.org/fpp/7/5
[6] Anderson, D., Sweeney, D., Williams, T., 2011, ―Statistics for
Business and Economics‖, Eleventh Edition, CENGAGE
Learning pub., NEWYORK.
[7] Box, G.E.P. and Jenkins, G.M., 1976, ―Time series analysis
Forecasting and control, Holden-Day Inc., San Francisco.
[8] El-DABAGH, M., 2010, ―Design of Instant-Mail System using
infrastructure of information and communication technology‖,
Higher Diploma thesis, Mosul University – college of
Administration and Economic, (Arabic Reference).
[9] ESMAEEL, N., 1981, ―Determine the Arabian Crude oil
Prices in the world Market‖, AL-RASHID Pub., Baghdad
(Arabic reference).
[10] JAWAD, B., 2013, ―Wide Preaching and Information
Technology and their Impact on Achieving customers
satisfaction‖, Master thesis, Karbala University – college of
Administration and Economic, (Arabic Reference).
[11] MONEM M.A. 2011, ―The analysis and Forecasting in Time
series‖, SULIMANI University Pub., SULIMANI. (Arabic
reference).
[12] PADHY, N., and PANIGRAHI, R., 2012, ―Engineering
information Technology, International Journal of computer,
Vol.2, NO.5, Oct.
[13] RAJARAMAN, V., 2013, ―Introduction to Information
Technology‖, second edition, PHI learning Private Limited.
[14] SIM, C.H., 1978, ―AMIXED GAMMA ARAMA (1, 1) Model for
river flow Time Series‖, Water resources research, Vol.23,
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[15] SPYROS, M., Steven, C., and ROB, J., 1998, ―Forecasting
methods and applications‖.
[16] SULTAN, S., 2005, ―Health information technology and its
impact on job satisfaction – a study on opinions of sample of
health technologies users in Ibn Sina & El-Khansa
educational Hospital‖, Master thesis, University of MosulCollege of Administration and Economic, (Arabic Reference).
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