Econometric: Modification Technique of Fuzzy Time Series First
Order and Time-invariant Chen and Hsu to Increase the Forecasting
Accuracy of Value Stock Index in Indonesia
Rizka Zulfikar
1
, Ade Prihatini Mayvita
2
, Purboyo
3
Faculty of Economic- Islamic University Of Kalimantan Muhammad Arsyad Al Banjari Banjarmasin
Keywords: Stocks Forecasting, Fuzzy Time Series, Chen and Hsu, First Order And Time Invariant.
Abstract: This econometric research aims to develop the fuzzy time series - Chen and Hsu first order and time-
invariant for forecasting the value of stocks. Process modifications made to the methods of fuzzy time
series - Chen and Hsu because there are still some significant fluctuation variances in some period of data
and trend predictions do not fully follow the actual trend of the stock price movement. The modifications
had conducted at the redivided interval step and assuming that all group intervals data have the same
opportunity to improve the accuracy of forecasting. The data used in this research are the index of Jakarta
Stock Exchange (JSX) and index of LQ-45 from July to August 2017. The results of this research have
found that the modification of fuzzy time series at intervals redivided step able to provide better
forecasting accuracy.
1 INTRODUCTION
Fuzzy Time series Techniques is one of the
techniques that are currently developed for
forecasting and are widely used in predicting the
movement of the stock value. This technique uses a
first order time-invariant method which is included
in the concept of artificial intelligence and used to
conduct forecasting and economic magnitudes. This
technique was first proposed by Song and Chissom
(1993) which used the concept of logical fuzzy to
develop the basis of fuzzy time series using time-
invariant and time-variant for forecasting. Several
methods of fuzzy time series forecasting which have
been developed are a method of Chen (1996 and
2002) and Chen and Hsu (2004), the method of
Markov Chain (Sullivan and Woodall, 1994), the
method of percentage change (Stevenson and Porter,
2009), the implementation of the network back
propagation (Huarng and Yu,2006), and multiple-
attribute fuzzy time series (Cheng et al, 2008).
Forecasting with fuzzy time series has also been
tested by some researchers as practiced by Hansun
(2012) and Fauziah et al (2016) with Fuzzy Time
Series Chen, Rahmadiani (2012) with Fuzzy Neural
network, Handayani and Anggraini (2015) by the
method of Chen and the method of Lee, Rukhansyah
Et all (2015) with Fuzzy Time Series Markov Chain,
Hasudungan (2016) with Fuzzy Time Series-Genetic
Algorithm and Elfajar et al (2017) with fuzzy time
series invariant.
Further research on fuzzy time series conducted
by Zulfikar and Mayvita (2017) who conducted tests
on Fuzzy Time Series Chen and Hsu to predict the
value of the sharia stock index in Jakarta Islamic
Index. The results obtained were tested methods
provide predictions quite well with the value of
Mean Square Error (MSE) = 1.88 and an error
Average Forecasting Error Rate (Afer) = 0.006%,
although still found the existence of some
fluctuation variance was significant in a period of
data and looks that the trend prediction of stock
movement within some period of time did not fully
follow the actual trend of sharia stock price
movement in the Jakarta Islamic Index. Based on
this, it can be said that the method of fuzzy time
series - Chen and Hsu still gave the weakness in
predicting the stock value for some period of time.
2 METHODS
Our population and sample used in this research
were daily data index of the Jakarta Stock Exchange
Zulfikar, R., Mayvita, A. and , P.
Econometric: Modification Technique of Fuzzy Time Series First Order and Time-invariant Chen and Hsu to Increase the Forecasting Accuracy of Value Stock Index in Indonesia.
DOI: 10.5220/0009022100002297
In Proceedings of the Borneo International Conference on Education and Social Sciences (BICESS 2018), pages 421-428
ISBN: 978-989-758-470-1
Copyright
c
2022 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved
421
(JSX) and the LQ-45 index period from January 10,
2017, until August 10, 2017 Data used in this
research is secondary data obtained from sites
finance google (www.finance.google. com).
This method is used 5 (five) following steps:
(1) Defining the universal of data collection,
(2) SDistributing Data to the universal of data
collection, (3) Defining the fuzzy sets, (4)
Performing the Fuzzy Logical Relationship (FLR)
and (5) Determining the difference of data n-1 and
n-2 Data based on 3 (three) rules of fuzzy time series
first order and time-invariant Chen and Hsu as
explained in Table 1 below.
Table 1. Rule Fuzzy Time Series First Order Time-Invariant (Chen and Hsu, 2004)
Rule 1 Rule 2 Rule 3
If the data does not have data n-2
and n-3, then used is the middle
value of Fuzzy set A
j.
If the data does not have data n-3,
then:
a. if the difference between n-1
and n-2> half intervals A
j
then
the value is expressed as
upward forecast 0.75 point
interval A
j.
b. if the difference between n-1
and n-2 = half interval A
j
then
the value is expressed as a
middle-value prediction
intervals A
j.
c. if the difference between n-1
and n-2 <half the interval A
j
then the value is expressed as
downward interval forecast A
j.
If DIFF is worth positive then:
a. if the value (DIFF x 2 + Data
n-1) Not in the interval A
j
then
the value is expressed as
upward forecast 0.75 point
interval A
j.
b. if the value (DIFF / 2 + Data
n-1) Not in the interval A
j
then
the value is expressed as
downward 0:25 forecasts point
interval A
j.
c. Point (a) and point (b) is not
met, then the value of the
forecast stated at the middle
interval value A
j
If DIFF is negative then:
a. if the value (DIFF / 2 + Data
n-1) No in the interval A
j
then
the value is expressed as
downward 0:25 forecasts point
interval A
j.
b. if the value (DIFF x 2 + Data
n-1) No in the interval A
j
then
the value is expressed as
upward forecast 0.75 point
interval A
j.
c. If Point (a) and point (b) is not
met, then the value of the
forecast stated at the middle-
value intervals A
j.
2.1 Modification Technique
Technique modifications made in this study is
performed at redivided interval step in which is
conducted by dividing the interval by the number
smallest data first into two parts of equal length, the
interval with the amount of data the second smallest
to 3 equal lengths, interval by the number of data
third smallest into 4 parts of equal length, and so on
until the entire interval is divided into several
subintervals of equal length.
2.2 Operational Definitions
The operational definition used in this study are:
1. Mean Square Error (MSE), MSE is used to
compare the accuracy of various methods of
forecasting (Chen and Hsu, 2004)[4], where the
formula for calculating the MSE is as follows:
MSE =(Historical data -Data actual results of
forecasting2)/Total Data
(1)
2. Average Forecasting Error Rate (AFER),
AFER is used to determine the amount of data
errors occurring in forecasting results against
actual data (Jilani, Burney and Ardil, 2007)
which is calculated based on the following
equation:
AFER =
| |

x 100%
(2)
3 RESULT
Data description that used in this research for JSX
and LQ-45 are showed in Table 2.
Table 2. Data Description (Stock Exchange Index of JSX
and LQ-45)
No Description JSX LQ-45
1 Number 150 data 150 data
2 Maximum 5250.97 875.51
3 Minimum 5915.36 997.51
4 Variance Maximum 59.81 13.46
5 Variance Minimum -146.43 -28.95
6 Number of Intervals 7 7
7 Length of Intervals 100 100
BICESS 2018 - Borneo International Conference On Education And Social
422
After knowing the length and number of intervals,
the next step is distributed all data into each interval
and the results showed in Table 3 and Table 4 which
is explained intervals before and after modification
for JSX (Table 3) dan LQ-45 (Table 4).
Table 3. Comparison Redivided Interval between Fuzzy Time Series Before Modification and After Modification For JSX
Index Data
No Code Length Number
Of
Data
Before Modification After Modification
1 U1 [5250-5350] 18 Divided
Into 2
Intervals
U1.1, U1.2 Divided
Into 5
Intervals
U1.1,U1.2,
U1.3,U1.4,
U1.5
2 U2 [5350-5450] 28 Divided
Into 3
Intervals
U2.1,
U.2.2, U2.3
Divided
Into 6
Intervals
U2.1,U2.2,
U2.3, U2.4,
U2.5, U2.6,
U2.7
3 U3 [5450-5550] 6 Not Change U3 Divided
Into 2
Intervals
U3.1,U3.2
4 U4
[
5550 -5650] 17 Not Change U4 Divided
Into 4
Intervals
U4.1,U4.2,
U4.3,U4.4
5 U5
[
5650 -5750] 35 Divided
Into 4
Intervals
U5.1, U5.2,
U5.3, U5.4
Divided
Into 7
Intervals
U5.1,U5.2,
U5.3,U5.4,
U5.6,U5.7
6 U6
[
5750 -5850] 35 Divided
Into 4
Intervals
U6.1, U6.2,
U6.3, U6.4
Divided
Into 7
Intervals
U6.1,U6.2,
U6.3,U6.4,
U6.6,U6.7
7 U7
[
5850 -5950] 11 Not Change U7. Divided
Into 3
Intervals
U7.1,
U7.2,U7.3
Table 4. Comparison Redivided Step Interval between Before and After Modification for LQ-45 Index Data
No Code Interval Number O
f
Data
Universe Before
Modification
Universe After
Modification
1 U1 [875-895] 35 Divided
Into 4
intervals
U1.1, U1.2,
U1.3, U1.4
Divided
Into 6
intervals
U1.1, U1.2,
U1.3, U1.4,
U1.5, U1.6
2 U2 [895 - 915] 11 Not Change U2 Divided
Into 2
intervals
U2.1, U2.2,
3 U3 [915 - 935] 20 Not Change U3 Divided
Into 3
intervals
U3.1, U3.2,
U3.3
4 U4 [935 - 955] 27 Divided
Into 2
interval2
U4.1, U4.2 Divided
Into 4
intervals
U4.1, U4.2,
U4.3, U4.4
5 U5 [955 - 975] 34 Divided
Into 3
interval2
U5.1, U5.2,
U5.3
Divided
Into 5
intervals
U5.1, U5.2,
U5.3, U5.4,
U5.5
6 U6 [975 - 995] 22 Not Change U6 Divided
Into 4
intervals
U6.1, U6.2,
U6.3, U6.4
7 U7 [995-1015] 1 Not Change U7 Not Change U7
Econometric: Modification Technique of Fuzzy Time Series First Order and Time-invariant Chen and Hsu to Increase the Forecasting
Accuracy of Value Stock Index in Indonesia
423
Furthermore, redivided step results as shown in table
3 and 4 are distributed into each new interval and
followed by a phase of defining the fuzzy set which
describe in Table 5 (for JSX) and Table 6 (for LQ-
45).
Table 5. Defining the fuzzy sets After Modification For JSX Index Data
Fuzzy
Set
Length Min Max
Fuzzy
Set
Length Min Max
A1 50.00 5250 5300 A9 25.00 5675 5700
A2 50.00 5300 5350 A10 25.00 5700 5725
A3 33.33 5350 5383 A11 25.00 5725 5750
A4 33.33 5383 5417 A12 25.00 5750 5775
A5 33.33 5417 5450 A13 25.00 5775 5800
A6 100.00 5450 5550 A14 25.00 5800 5825
A7 100.00 5550 5650 A15 25.00 5825 5850
A8 25.00 5650 5675 A16 100.00 5850 5950
Table 6. Defining Fuzzy Set After Modification for LQ-45 Index Data
Fuzzy
Set
Length Min Max
Fuzzy
Set
Length Min Max
A1
2.50
875 877.5 A19
3.33
945 948
A2
2.50
878 880 A20
3.33
948 952
A3
2.50
880 882.5 A21
3.33
952 955
A4
2.50
882.5 885 A22
2.86
955 958
A5
2.50
885 887.5 A23
2.86
958 961
A6
2.50
887.5 890 A24
2.86
961 964
A7
2.50
890 893 A25
2.86
964 966
A8
2.50
893 895 A26
2.86
966 969
A9
6.67
895 902 A27
2.86
969 972
A10
6.67
902 908 A28
2.86
972 975
A11
6.67
908 915 A29
4.00
975 979
A12
5.00
915 920 A30
4.00
979 983
A13
5.00
920 925 A31
4.00
983 987
A14
5.00
925 930 A32
4.00
987 991
A15
5.00
930 935 A33
4.00
991 995
A16
3.33
935 938 A34
10.00
995 1005
A17
3.33
938 942 A35
10.00
1005 1015
A18
3.33
942 945
The advanced stages such as forming Fuzzy
Logical Relationship (FLR) and determine the
difference of the data n-1, n-2 and n-3 by 3 (three)
rule fuzzy time Chen - Hsu carried out in accordance
technique Chen fuzzy time - Hsu without any
modifications (see also Zulfikar and Mayvita, 2017)
After analysis of actual data, the final result and
the predicted value of the JSX and LQ-45 which
presented to 30 dataobtained after modification of
the technique is showed in Table 7 (for JSX) and
Table 8 (for LQ-45).
BICESS 2018 - Borneo International Conference On Education And Social
424
Table 7. Actual and Predicted JSX Index with Modified Technique
No Tanggal FLR Actual Predicted Variance AFER
1
10-Jan-17
A3 A2 5292.75 885.63 -2.250 -0.04%
2
11-Jan-17
A2 A2 5272.98 883.75 -7.020 -0.13%
3
12-Jan-17
A2 A1 5270.01 878.75 -9.990 -0.19%
4
13-Jan-17
A1 A3 5266.94 878.13 6.940 0.13%
5
17-Jan-17
A3 A3 5294.78 886.25 -5.220 -0.10%
6
18-Jan-17
A3 A1 5298.95 886.25 -1.050 -0.02%
7
19-Jan-17
A1 A1 5254.31 876.25 -5.690 -0.11%
8
20-Jan-17
A1 A3 5250.97 876.25 -9.030 -0.17%
9
23-Jan-17
A3 A3 5292.09 883.75 -7.910 -0.15%
10
24-Jan-17
A3 A4 5293.78 883.75 -6.220 -0.12%
11
25-Jan-17
A4 A4 5317.63 888.75 -2.370 -0.04%
12
26-Jan-17
A4 A3 5312.84 886.25 -7.160 -0.13%
13
27-Jan-17
A3 A3 5302.66 883.13 7.660 0.14%
14
30-Jan-17
A3 A4 5294.10 876.25 -0.900 -0.02%
15
31-Jan-17
A4 A6 5327.16 886.25 7.160 0.13%
16
1-Feb-17
A6 A6 5353.71 891.25 -4.623 -0.09%
17
2-Feb-17
A6 A8 5360.77 893.75 6.603 0.12%
18
3-Feb-17
A8 A7 5396.00 898.33 4.333 0.08%
19
6-Feb-17
A7 A6 5381.48 898.33 6.480 0.12%
20
7-Feb-17
A6 A7 5361.09 893.75 6.923 0.13%
21
8-Feb-17
A7 A7 5372.08 894.38 -2.920 -0.05%
22
9-Feb-17
A7 A9 5371.67 893.75 -3.330 -0.06%
23
10-Feb-17
A9 A7 5409.56 898.33 1.227 0.02%
24
13-Feb-17
A7 A7 5380.67 893.75 5.670 0.11%
25
14-Feb-17
A7 A6 5378.00 893.75 3.000 0.06%
26
15-Feb-17
A6 A6 5350.93 886.25 -7.403 -0.14%
27
16-Feb-17
A6 A5 5359.29 888.75 0.957 0.02%
28
17-Feb-17
A5 A6 5340.99 886.25 0.990 0.02%
29
21-Feb-17
A6 A7 5358.68 891.25 0.347 0.01%
30
22-Feb-17
A7 A8 5372.75 893.75 -2.250 -0.04%
Table 8. Actual and Predicted LQ-45 Index with Modified Technique
No Tanggal FLR Actual Predicted Variance ESER
1
10-Jan-17
A5 A4 885.22 885.63 -0.405 -0.05%
2
11-Jan-17
A4 A2 882.52 883.75 -1.230 -0.14%
3
12-Jan-17
A2 A2 879.53 878.75 0.780 0.09%
4
13-Jan-17
A2 A5 878.90 878.13 0.775 0.09%
5
17-Jan-17
A5 A5 885.28 886.25 -0.970 -0.11%
6
18-Jan-17
A5 A1 886.48 886.25 0.230 0.03%
7
19-Jan-17
A1 A1 875.51 876.25 -0.740 -0.08%
8
20-Jan-17
A1 A4 875.86 876.25 -0.390 -0.04%
9
23-Jan-17
A4 A4 884.17 883.75 0.420 0.05%
10
24-Jan-17
A4 A6 884.31 883.75 0.560 0.06%
11
25-Jan-17
A6 A5 889.22 888.75 0.470 0.05%
12
26-Jan-17
A5 A4 886.62 886.25 0.370 0.04%
13
27-Jan-17
A4 A1 882.74 883.13 -0.385 -0.04%
Econometric: Modification Technique of Fuzzy Time Series First Order and Time-invariant Chen and Hsu to Increase the Forecasting
Accuracy of Value Stock Index in Indonesia
425
No Tanggal FLR Actual Predicted Variance AFER
14
30-Jan-17
A1 A5 877.35 876.25 1.100 0.13%
15
31-Jan-17
A5 A7 886.24 886.25 -0.010 0.00%
16
1-Feb-17
A7 A8 891.04 891.25 -0.210 -0.02%
17
2-Feb-17
A8 A9 893.30 893.75 -0.450 -0.05%
18
3-Feb-17
A9 A9 899.48 898.33 1.147 0.13%
19
6-Feb-17
A9 A8 896.64 898.33 -1.693 -0.19%
20
7-Feb-17
A8 A8 893.89 893.75 0.140 0.02%
21
8-Feb-17
A8 A8 894.45 894.38 0.075 0.01%
22
9-Feb-17
A8 A9 893.89 893.75 0.140 0.02%
23
10-Feb-17
A9 A8 900.72 898.33 2.387 0.26%
24
13-Feb-17
A8 A8 893.72 893.75 -0.030 0.00%
25
14-Feb-17
A8 A5 894.40 893.75 0.650 0.07%
26
15-Feb-17
A5 A6 887.40 886.25 1.150 0.13%
27
16-Feb-17
A6 A5 888.20 888.75 -0.550 -0.06%
28
17-Feb-17
A5 A7 886.34 886.25 0.090 0.01%
29
21-Feb-17
A7 A8 891.78 891.25 0.530 0.06%
30
22-Feb-17
A8 A9 893.11 893.75 -0.640 -0.07%
After performing analysis of actual data, the
obtained results from the fuzzy time series Chen and
Hsu before and after modification for JSX and LQ-
45 are described in Table 9 and we illustrade in
Figure 1,2,3 and 4 below.
Table 9. Comparison of MSE and AFER before and after Modification
Parameter
Before Modification After Modification
JSX LQ-45 JSX LQ-45
Variance 3.782 -0.419 0.4761 0.114
MSE 378.471 25.553 50.827 1.277
AFER 0.0685 % -0.0449 % 0.0081% 0.0120 %
Figure 1. Comparison Actual and Predicted JSX Index before Modification
5220
5230
5240
5250
5260
5270
5280
5290
5300
5310
Actual
Predicted
BICESS 2018 - Borneo International Conference On Education And Social
426
Figure 2. Comparison Actual and Predicted JSX Index after Modification
Figure 3. Comparison Actual and Predicted LQ-45 Index Before Modification
Figure 4. Comparison Actual and Predicted LQ-45 Index after Modification
Based on Figure 1 and Figure 3 shows that
the stock value of JSX and LQ-45 before the
modification still showed some significant variances
and can decrease the value of forecasting accuracy
index value. However, this is not shown in figure 2
and figure 4 that do forecasting with technical
5220
5230
5240
5250
5260
5270
5280
5290
5300
5310
Actual
Predicted
850
860
870
880
890
900
910
920
Actual
Predicted
860
865
870
875
880
885
890
895
900
905
Actual
Predicted
Econometric: Modification Technique of Fuzzy Time Series First Order and Time-invariant Chen and Hsu to Increase the Forecasting
Accuracy of Value Stock Index in Indonesia
427
modifications and line index value between actual
and predicted tends to coincide and be able to follow
the pattern of the value of stock index JSX and LQ-
45.
4 CONCLUSIONS
This research showed that the index of JSX after
using the technique of a modified fuzzy time series
is able to provide value Mean Square Error (MSE) =
0.476, and Average Forecasting Error (AFER) =
0.0081% where the obtained value is much lower
than is possible using Fuzzy Time Series unmodified
(MSE = 3,782 and AFER = 0.0685%). On the index
of LQ-45, the modified fuzzy time series technic is
able to provide the MSE = -0.0449 and AFER =
0.0120% which is also lower than the prediction
using the technique of fuzzy time series unmodified
(MSE = -0.419 and AFER = 0.114% ). The results
of this research have found that the modification of
fuzzy time series at intervals redivided step able to
provide better forecasting accuracy.
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