Page 1 of 6
Journal for Studies in Management and Planning
Available at http://internationaljournalofresearch.org/index.php/JSMaP
e-ISSN: 2395-0463
Volume 01 Issue 02
March 2015
P a g e | 230 Available online: http://internationaljournalofresearch.org/
Forecast of Adult Literacy in Sudan
Dr. Elfarazdag Mahjoub Mohammed Hussein,
Department of Statistics-Faculty of Science-Tabuk University (KSA), Sudan
Abstract:
The main objective of this paper is to
find out a time series model to monitor
and forecast the Adult Literacy rate in
Sudan. To achieve this objective, a
series of Adult Literacy ranged from
1990 to 2009 was obtained from the
Sudan Central Bureau of statistics and
United Nation Annual Reports, time
series analysis technique mainly box
and Jenkins were used to find the
required model .Analysis done by e- views package. The paper conclude
that The most proper time series
model to forecast the Adult Literacy
rate in Sudan is the ARIMA model,
The general trend of Adult Literacy is
an increasing trend with annual
increase Less than 3%.
Keywords: Adult Literacy, box and
Jenkins, auto regressive moving average,
Sudan.
Literacy is typically described as the ability to
read and write. It is a concept claimed and
defined by a range of different theoretical
fields. The United Nations Educational,
Scientific and Cultural Organization
(UNESCO) provides a useful and reasonably
definition of literacy, it is defined as the
"ability to identify, understand, interpret,
create, communicate, compute and use printed
and written materials associated with varying
contexts. Literacy involves a continuum of
learning in enabling individuals to achieve
their goals, to develop their knowledge and
potential, and to participate fully in their
community and wider society."
The aim of the study is to find out a time series
model based on annual basis for the Adult
Literacy rate in Sudan for the period 1990-
2009.
The importance of this study concentrated at
the serious need of constructing a time series
model for the future forecast to detect the
pattern of change in Adult Literacy which
helps for the future planning.
The used Adult literacy data was compiled
from the annual United Nations Development
Program Reports starting from 1990 up to 2009
will be used.
2. Theoretical framework
Time series analysis techniques, namely Box
and Jenkins technique was used, the series
extends over the period 1990-2013, which is
fairly long; Autoregressive Integrated Moving
Average (ARIMA) was chose for the analysis.
2.1 Time Series Components
Time series consists of several components,
which are:
(A) Trend
(B) Cyclical Variations.
(C) Seasonal Variations.
(D) Irregular fluctuations.
2.2 Time Series Decomposition Model
If a time series exhibits trend effects and
seasonal effects, it can be useful to decompose
it in order to isolate these effects. One model
that allows us to do this is the multiplicative
decomposition model, it’s the most popular
decomposition model, and it’s expressed as
Page 2 of 6
Journal for Studies in Management and Planning
Available at http://internationaljournalofresearch.org/index.php/JSMaP
e-ISSN: 2395-0463
Volume 01 Issue 02
March 2015
P a g e | 231 Available online: http://internationaljournalofresearch.org/
follows:
t t t t t Y = T * S * C * I
Also there is decomposition model known as
the additive model, which expressed as
follows:
t t t t t Y = T + S + C + I
Where:
Yt: The observed value of the time series in
time period t.
Tt: The trend components in time period t.
St: The seasonal components in time period t.
Ct: The cyclical components in time period t.
It: The erratic components in time period t.
2. 3 Forecasting Methods
There are many forecasting methods that can
be divided into two basic types which are:
(A) Qualitative Forecasting Methods
Qualitative forecasting methods generally use
the opinion of the expert to subjectively predict
future events.
(B) Quantitative Forecasting Methods
Quantitative forecasting models are grouped
into two main models, which are:
(I) Univariate Models
Univariate models predict the future events of
time series on the basis of the past values of the
time series (Powerman, 1979) .When a
univariate model is used; historical data are
analyzed in an attempt to identify a data
pattern, then assuming that it will continue in
the future. Univariate forecasting models are
most useful when conditions are expected to
remain the same.
(II) Causal Models
The use of such models involves the
identification of other variables that are related
to the variable to be predicted, once these
related variables have been identified, a
statistical model that describes the
relationships between these variables and the
variable to be forecasted is developed. The
statistical relationship derived is then used for
forecasting the variable of interest.
Generally we can say that quantitative
forecasting methods are used when historical
data are available univariate models predict
future values of the variable of interest on the
basis of historical pattern of that variable,
assuming the historical pattern will continue;
causal models predict future values of the
variable of interest based on the relation
between that variable and other variables.
Qualitative forecasting techniques are used
when historical data are scarce or not available
at all and depend on the opinions of experts
2.4 Choosing the Forecast Technique
In choosing the forecasting technique the
forecaster must consider the following factors
1. The nature of the study variable.
2. The time frame.
3. The pattern of data.
4. The cost of forecasting.
5. The accuracy desired.
6. The availability of data.
7. The ease of operation and understanding.
The first factor to be considered in choosing a
forecasting method is the form in which the
forecast is desired i.e. determine whether the
forecaster will use point or interval forecast.
The second factor that can influence the choice
of forecasting method is the time frame of the
forecasting situation. Forecast are generated for
point in time may be a number of days , weeks,
months, quarters or years in the future. This
Page 3 of 6
Journal for Studies in Management and Planning
Available at http://internationaljournalofresearch.org/index.php/JSMaP
e-ISSN: 2395-0463
Volume 01 Issue 02
March 2015
P a g e | 232 Available online: http://internationaljournalofresearch.org/
length of time is called the time frame; the
length of the time frame is usually categorized
as follows:
1. Immediate less than month.
2. Short term more than three months to less
than two years.
3. Long term two years or more.
The length of the time frame influence the
choice of forecasting technique, typically a
longer time frame makes accurate forecasting
more difficult.
The pattern of data must also be considered
when choosing forecasting model. Thus, it is
important to identify the existing data pattern.
One of the most important factor that affect the
choice of forecasting technique is the desired
accuracy of the forecast, the availability of
information and last the ease with which the
forecasting method is operated and understood
is important.
2.5 The Box-Jenkins Methodology
This methodology developed by G. E. P. Box
and G. M. Jenkins, consists of four basic steps.
The first step, called tentative identification
step, involves tentatively identifying a model.
Once a model has been identified, we estimate
the model parameters in the second step that
called the estimation step. The third step is
called the diagnostic checking step, here we
check the adequacy of the model, if the model
proves to be inadequate, it must be modified.
When a final model is determined, we use the
model to forecast future time series values; this
fourth step is called the forecasting step.
There are many Box-Jenkins models; these
models can be grouped into the following three
basic classes:
(A) Autoregressive models.
(B) Moving average models.
(C) Mixed autoregressive- moving average
models.
Box-Jenkins models are often called ARIMA
models [Autoregressive Integrated Moving
Average]. The Univariate Box – Jenkins
models have proven to provide accurate
forecast in short term forecasting applications.
2.6 Stationary and Non-Stationary Time
Series
The classical Box – Jenkins models describe
stationary time series, thus in order to
tentatively identify a Box – Jenkins models, we
must first determine whether or not a time
series under investigation is stationary, if it is
not, we must transform it into a series of
stationary time series values either by using the
log or the reciprocal. A time series is said to be
stationary if the statistical properties such as
mean and variance of time series are constant
through time , if we have observed n values y1,
y2, y3, ...., yn , of a time series, we can use a
plot of these values against time to help us to
determine whether the time series is stationary
or not. If the n values seem to fluctuate with
constant variation around a constant mean,
then it is reasonable to believe that the time
series is stationary, if the n values do not
fluctuate with constant variation, then it is
reasonable to believe that the time series is no
stationary. If we decided that the time series is
not stationary we can transform it from non- stationary to stationary by taking the first
differences of the non-stationary time series.
2.7Unit Root Test -Augmented Dickey- Fuller (DF) Test
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