Comparing the performances of GARCH models in capturing the stock market volatility in Malaysia

Comparing the performances of GARCH models in capturing the stock market volatility in Malaysia
Comparing the performances of GARCH models in capturing the stock market volatility in Malaysia

P rocedia Economics and Finance 5 ( 2013 ) 478 – 487

2212-5671 ? 2013 The Authors. Published by Elsevier B.V.Selection and/or peer-review under responsibility of the Organising Committee of ICOAE 2013d oi: 1

0.1016/S2212-5671(13)00056-7

Available online at https://www.360docs.net/doc/aa15963483.html,

ScienceDirect

Open access under CC BY -NC-ND license.

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C hing Mun Lim and Siok Kun Sek / P rocedia Economics and Finance 5( 2013 )478 – 487

stock market provide useful information in measuring risk, many models/ theory are applied in forecasting stock market movement and evaluating the performance of the stock market. Many studies show that random walk model is superior in explaining the stock market movement. However, more recent studies reveal results that stock market deviates from the random walk behaviour. We further the investigation on stock market movement by looking at different aspects (i.e. different models and different time frames).

Among the models that have been applied to capture the stock market volatility include ARCH which was proposed by Engle (1982) and generalized ARCH proposed by Bollerslev (1986) and Taylor (1986). After the introduction of ARCH and GARCH models, many researchers have proposed the extensions and alternative specifications on the models such as GARCH-M, IGARCH, EGARCH (Nelson (1991)), Threshold GARCH (Glosten et al. (1993)), Asymmetric GARCH model AGARCH (Engle (1990)) and Fractionally Integrated FIGARCH (Baillie et al. (1996)). These alternative models seek to improve the GARCH model in capturing the characteristics of return series. However, previous studies show no consensus on the best model in capturing volatility. Some studies show preferable results using simple GARCH (p,q) models but some show extensions of GARCH models perform better. The performance of these models varies across markets and time period. The performance of these forecast models is affected by error measures.

In this study, we seek to identify the superior model in capturing the characteristics of Malaysia’s stock market. The models to be compared are symmetric GARCH and asymmetric GARCH (EGARCH and TGARCH). In particular, we evaluate the performance of these models using the error measurement approaches such as MSE, RMSE and MAPE. Apart from this, we also seek to investigate if exchange rate can influence the stock market movement in Malaysia. The results are compared for three different time frames

i.e. pre-crisis, crisis period and post-crisis periods. Our results show that the performance of GARCH-type models is dependent on the time/ periods, i.e. during pre-crisis, crisis and post-crisis and also the error measures. In general, the total rank show that GARCH/ TGARCH model perform the best in the pre-crisis period while GARCH model works well during the crisis and TGARCH model work well in the post-crisis period in capturing the stock market volatility in Malaysia.

The remaining paper is organized as follows: section two provides some concepts and literature reviews. Section three is about the data and methodology. Section four is about model evaluations while section five summarizes the findings. Section six concludes.

2.Literature review

The study on stock market volatility is broad. Empirical studies apply GARCH and ARCH models in capturing the stock market volatility. These studies cover different regions/ countries. The studies that focus

on stock market in developed countries (United States, United Kingdom, Germany, and Japan) include Claessen & Mittnik (2008), Ou & Wang (2011), Choo & Lee (2011), and Mootamri (2011). These studies applied different frequency data. Among the studies that focused on the stock market in developing countries (Malaysia, Singapore, India, Saudi, China, Egypt and Vietnam) are Mishra (2010), Alshogeathri (2011), Abdalla (2012), Wong & Kok (2005) and Liu et al. (2009), Hien (2008).

In evaluating the performance of models, previous studies apply different evaluation measures. The most widely applied measures include Mean Square Error (MSE), Root Mean Square Error (RMSE), and Mean Absolute Percent Error (MAPE). In practice, when comparing the different models, it is rarely the case that one model dominate the other with respect to all evaluation measures. The common way to solve the problem

is to carry out the average figures of some statistical measures and then compare the forecast models based on the parameter obtained.

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shocks) and GARCH term 1E (long-run persistency of shocks) for GARCH (1, 1) are highly significant in all

periods, indicating the impacts of shocks on stock market volatility (the results is not provide here due to space constraint). Comparing the results of asymmetric and asymmetric models, we observe that the coefficient of J for TGARCH and EGARCH are insignificant at pre-crisis period. The result implies no significant asymmetric effect of shocks on stock market volatility. Therefore, linear model is sufficient to model the volatility of stock market in the pre-crisis period. On the other hand, there are significant asymmetric effects of shocks during the crisis and post-crisis periods in Malaysia. Therefore, asymmetric models are the better models used to represent the stock market volatility during the economic fluctuation periods (crisis period) and economic recovery period (post crisis). The effect of asymmetric shocks is larger during the crisis period, indicating larger leverage effect during crisis period relative to post-crisis period. Next, comparing the effects of short run and long run persistency of shocks (1D and 1E ), our results reveal that long-run shocks are more persistent compared to short-run shocks, indicating larger impacts of long-run shocks on stock market volatility. The result holds for all three periods and three models.

Investigating the impacts of exchange rate and crude oil price on stock market volatility, we observe that both variables only have small impacts or non-significance impacts on stock market volatility in Malaysia. The only exception is the result reported by EGARCH for the pre and post-crisis periods. Our results imply that both variables fail to explain the stock market volatility during the crisis period when the stock index is highly fluctuated. During the stable periods (pre and post-crisis), exchange rate and crude oil price have some powers on predicting stock market volatility.

The three GARCH-type models are evaluated using three measurements, i.e. mean square error (MSE), root mean squared error (RMSE) and mean absolute percent error (MAPE). 5.1. In sample analysis

For in sample analysis, the models are estimated using the full sample with one month shorter, i.e. up to end of November 2010. The performance of the models is ranked from the lowest error. The total rank is the summation values of rank from the three measurements.

Table 1. Overall Model Evaluation (In Sample) Model

Errors Measures MSE

Ranking RMSE Ranking MAPE(%) Ranking Total Rank Pre Crisis Period GARCH 0.000157775 1 0.012560851 1 109.4740 2 4 TGARCH 0.000157776 2 0.012560891 3 107.3696 1 6 EGARCH 0.000157778

3

0.012560871

2

106.5497

3

8

Crisis Period GARCH 0.001184216 1 0.034412439 1 147.6658 1 3 TGARCH 0.001208099 3 0.034757718 3 222.9189 3 9 EGARCH 0.001189480 2 0.034488838 2 178.0566 2 6 Post Crisis Period

GARCH 0.000172664 2 0.013140167 2 107.7394 2 6 TGARCH 0.000172662 1 0.013140091 1 107.8859 3 5 EGARCH

0.000172887

3

0.013148650

3

101.2583

1

7

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C hing Mun Lim and Siok Kun Sek / P rocedia Economics and Finance 5( 2013 )478 – 487

Comparing the performance of symmetric and asymmetric GARCH models, our results of total ranks show that symmetric GARCH model is the best model to capture the stock market volatility in Malaysia during the pre- and crisis periods. On the other hand, TGARCH model is superior in the post-crisis period. However, one has to be caution because the ranking for these three measurements are different under three time frames. The values of errors do not vary much for MSE and RMSE but when the error is measured in percentage, the values are much more different.

5.2.Out of sample analysis

In this part, the out-of-sample forecast is performed for one month ahead from the full sample generating 20 observations.

Table 2 describes the overall evaluation for three models by using three error measures. The MSE statistic indicates that the TGARCH model provides the most accurate forecast for the pre-crisis period. The next ranked models are EGARCH and GARCH in that order. Besides, the RMSE implies that the TGARCH model provides the most accurate forecast for the pre-crisis period. The next ranked models are EGARCH and TGARCH in that order. The MAPE statistic indicates that EGARCH provides the most accurate forecast for the pre-crisis period. The next ranked models are TGARCH and the worst performing model is GARCH. In order to choose the best performing models, we used the total rank which generated from the ranking of three statistics. From the ranking of the three statistics, the total rank of TGARCH is the lowest in the pre- and post-crisis periods. Therefore, we indicate that TGARCH model outperform the other models in the pre- and post-crisis periods. On the other hand, GARCH model performs the best in the crisis-period.

Table 2. Overall Model Evaluation (Out of Sample)

Model Errors Measures

MSE Ranking RMSE Ranking MAPE(%) Ranking Total Rank

Pre Crisis Period

GARCH 0.000157564 3 0.012552449 3 109.4903 3 9

TGARCH 0.000157560 1 0.012552303 1 107.3061 2 4

EGARCH 0.000157561 2 0.012552322 2 106.4940 1 5

Crisis Period

GARCH 0.0011400015 1 0.033763909 1 144.0898 1 3

TGARCH 0.0011681337 3 .0341779715 3 217.4841 3 9

EGARCH 0.0011470467 2 0.033868078 2 173.6390 2 6

Post Crisis Period

GARCH 0.0001716995 2 0.013103418 2 107.8626 2 6

TGARCH 0.0001716994 1 0.013103413 1 107.8752 3 5

EGARCH 0.0001719257 3 0.013112042 3 101.2477 1 7

From the result of both in sample forecast and out of sample forecast, we found that the performance of GARCH-type models is affected by the period of time, i.e. pre-crisis, crisis and post-crisis periods. Using

486C hing Mun Lim and Siok Kun Sek / P rocedia Economics and Finance 5( 2013 )478 – 487 different error measures also give different evaluations on the ranking of performance. MSE and RMSE show very small differences in the performance of these three models. However, when the measurement is made in percentage using MAPE, the differences on the performance of these models are larger and more apparent. In general, the total rank show that GARCH/ TGARCH model perform the best in the pre-crisis period while GARCH model works well during the crisis and TGARCH model work well in the post-crisis period in capturing the stock market volatility in Malaysia. The evaluation results are consistent to the estimation results that show no significant asymmetric effect during the pre-crisis period, i.e. asymmetric GARCH model is sufficient to capture volatility in the pre-crisis period; there are significant asymmetric effect in the crisis and post-crisis period, implying possibility that asymmetric GARCH models work better than symmetric GARCH model.

6.Conclusion

We conduct comparative analyses in evaluating the forecasting performance of symmetric and asymmetric GARCH-type models in capturing stock market volatility in Malaysia. These models include GARCH, TGARCH and EGARCH models. These models are evaluated using three error measures which are MSE, RMSE and MAPE. We divide the data into three sub-periods, i.e. pre-crisis, crisis and post-crisis of 1Asia financial periods. Our results show that the performances of these models vary across periods and error measurement methods. . In general, the total rank show that GARCH/ TGARCH model perform the best in the pre-crisis period while GARCH model works well during the crisis and TGARCH model work well in the post-crisis period in capturing the stock market volatility in Malaysia. The evaluation results are coincide with the results of estimation which imply symmetric GARCH works well in the pre-crisis period and asymmetric GARCH model(s) can be the better model in capturing volatility of stock market Malaysia in the crisis and post-crisis periods.

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用GARCH模型预测股票指数波动率

用GARCI模型预测股票指数波动率 目录 Abstract ......................................................................... 1.引言........................................................................... 2.数据........................................................................... 3.方法........................................................................... 3.1.模型的条件平均............................................................ 32模型的条件方差............................................................... 3.3预测方法.................................................................... 3.4业绩预测评价............................................................... 4.实证结果和讨论................................................................. 5.结论........................................................................... References ....................................................................... Abstract This paper is designed to makea comparison between the daily conditional varianee through seven GRAChhodels. Through this comparison, to test whether advaneed GARCH models are outperform ing the sta ndard GARCH models in predict ing the varia nee of stock in dex. The database of this paper is the statistics of 21 stock in dices around the world from 1 January to 30 November 2013. By forecast ing one —step-ahead con diti onal varia nee within differe nt models, the n compare the results within multiple statistical tests. Throughout the tests, it is found that the sta ndard GARCH model outperforms the more adva need GARCH models, and recomme nds the best

用GARCH模型预测股票指数波动率

用GARCH模型预测股票指数波动率 目录Abstract (2) 1.引言 (3) 2.数据 (6) 3.方法 (7) 3.1.模型的条件平均 (7) 3.2.模型的条件方差 (8) 3.3预测方法 (9) 3.4业绩预测评价 (9) 4.实证结果和讨论 (12) 5.结论 (16) References (18)

Abstract This paper is designed to make a comparison between the daily conditional variance through seven GRACH models.Through this comparison,to test whether advanced GARCH models are outperforming the standard GARCH models in predicting the variance of stock index.The database of this paper is the statistics of21stock indices around the world from1January to30 November2013.By forecasting one–step-ahead conditional variance within different models, then compare the results within multiple statistical tests.Throughout the tests,it is found that the standard GARCH model outperforms the more advanced GARCH models,and recommends the best one-step-ahead method to forecast of the daily conditional variance.The results are to strengthen the performance evaluation criteria choices;differentiate the market condition and the data-snooping bias. This study impact the data-snooping problem by using an extensive cross-sectional data establish and the advanced predictive ability test.Furthermore,it includes a13years’period sample set, which is relatively long for the unpredictability forecasting studies.It is part of the earliest attempts to inspect the impact of the market condition on the forecasting performance of GARCH models.This study allows for a great choice of parameterization in the GARCH models,and it uses a broad range of performance evaluation criteria,including statistical loss function and the Mince-Zarnowitz regressions.Thus,the results are more robust and diffusely applicable as compared to the earliest studies. KEY WORDS:GARCH models;volatility,conditional variance,forecast,stock indices.

基于GARCH模型的沪深300指数收益率波动性分析

基于GARCH模型的沪深300指数收益率波动性分析

摘要 股票市场的价格波动研究,不仅具有重要的学术意义,而且具有重要的实际意义。股价的波动给投资者带来了获利的机会。因此,金融市场的波动性一直以来都是投资者和经济研究人员关注的焦点。 本文以对沪深300指数2005年1月4日到2014年6月11日每个交易日收盘价为原始数据,对其收益率进行了研究分析。研究结果表明:日收益率序列的波动表现出时变性、突发性和集簇性等特征。序列分布呈现出尖峰厚尾的特点,并且存在明显的GARCH效应,表明过去的波动对于未来的影响是持久的,同时也是逐渐衰减的。而且,沪深300指数波动幅度大。沪深300指数的频繁交易使得股指期货市场具有高流动性,这种高流动性也是造成指数波动的一大成因。 关键字:收益率;ARCH模型;GARCH模型

一、前言 1.1研究意义 股票市场的价格波动研究,不仅具有重要的学术意义,而且具有重要的实际意义。股价的波动给投资者带来了获利的机会。投资者可以通过对度量波动率来猜测股市的风险有多大,同时,了解波动性有助于投资者更好的理解和把我股票市场的运行规律,将股价界定在一个可能的范围内,当投资者认识到股价波动的规律,就可以帮助其做出明智的投资,以获取更多的利益。因此,金融市场的波动性一直以来都是投资者和经济研究人员关注的焦点。 1.2 研究对象和方法 沪深300指数是由上海和深圳证券市场中选取300只A股作为样本编制而成的成份股指数。沪深300指数选取规模大、流动性好的股票作为样本, 覆盖了沪深市场六成左右的市值,具有良好的市场代表性,所以有必要对其进行深入分析。 本文以中国金融期货交易所的沪深300指数2005年1月4日到2014年6月11日每个交易日收盘价为原始数据,共2288个数据样本。 就沪深300指数收益率的波动性研究方法而言,国内外的研究结果表明,许多金融时间序列都将GARCH模型作为解释金融数据的经验方法。因此,本文采用GARCH模型检验沪深300指数日收益率的波动性变化,希望可以发现沪深300指数的波动性特征。 二、GARCH模型介绍 2.1 ARCH模型 ARCH模型由Engle(1982)提出,并由Bollerslev(1986)发展成为GARCH-广义自回归条件异方差。这些模型广泛的应用与经济性的各个领域,尤其是金融时间序列中。 ARCH的核心是(1)式中t时刻的随机误差项ε的方差(σ2)依赖于t-1时刻的平方误差的大小,即依赖于ε2t?1。 Y t=β0+β1X1t+?+βk X kt+εt (1)

波动率于garch模型剖析

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