Asset pricing model and efficiency porfolio investment on difference foreign ownership evidence from vietnam stock market

Asset Pricing Model And Efficiency Porfolio Investment On Difference Foreign Ownership: Evidence From Vietnam Stock Market Anh Phong Nguyen Hoang Anh Nguyen Thi Hong Minh Ho Phu Thanh

Asset Pricing Model And Efficiency Porfolio Investment

On Difference Foreign Ownership: Evidence From

Vietnam Stock Market

Anh Phong Nguyen Hoang Anh Nguyen Thi Hong Minh Ho Phu Thanh Ngo

University of Economics and Law, Vietnam National University - HCMC, Vietnam

Abstract

This study aims at assessing the risk – return profile of stock portfolios by different levels of the foreign ownership ratio The article also evaluates the performance of portfolios by their size and the book-to-market ratio (BTM) In this study, we apply GMM approach with the data computed from stock related data based in Ho Chi Minh Stock Exchange and Ha Noi Stock Exchange for the period 2010-2017 Our findings reveal a pronounced foreign ownership impact, whereby the increase in the foreign ownership ratio results in the upturn in stocks’ liquidity, return and size but also brings about the higher risk for stocks Besides, our empirical analyses indicate that the portfolios with the foreign ownership ratio falling either to the bottom 20% or to the top 20% outperform other portfolios In addition, the study suggests that investors could consider the large-size portfolio with the medium level of BTM as well as the small-size portfolio with the high level of BTM

Keywords: Foreign ownership, pricing model, risk and return of stock portfolio

JEL Classification : C58, E22, G12, G38

1.Introduction

A considerable amount of literature has been published on asset pricing models since the 1970s Until now, there remains three research approaches on this topic: The first approach, which are typically represented by Fama-French’s studies (1992, 1993), claims that the risk of assets arises by anomalies beyond the market risk factor because their returns may fluctuate

in the same way but different from the market The second one, which is supported by Daniel-Titman (1997), suggests that there are other risk factors simply because of the companies’ characteristics The third one, which is consider the return into different portfolios based on portfolios of independent variables, such as ownership variation or investment variation; this one is demonstrated in studies of Söhnke M Bartram, John Griffin, and David Ng (2004, 2015)

However, few investigations have applied the pricing model to assess the fluctuations in return and risk of stock portfolios with respect to the difference in foreign ownership ratio among many stock markets around the world For instance, Söhnke M Bartram, John Griffin, and David Ng (2004, 2015) examined the fluctuations in return and risk of portfolios with

different foreign ownership structure from developed and emerging stock markets The studies ofNildagBasakCeylan, BurakDogan& M HakanBerument (2015) on Borsa Istanbul stock market

or Roger D Huang and Cheng-Yi Shiu (2009) on Taiwan stock market generated similar issues Moreover, the study on the risk – return profile of stock portfolios by different levels of the foreign ownership

ratio has not been applied in Vietnam stock market, which is considered to get promoted from a frontier market to an emerging market

Vietnam stock market was officially launched in 2000 After 17 years of establishment and development; nevertheless, in comparison with other countries, Vietnam stock market is still

an emerging market with small size and limited liquidity Especially, the market depends highly on institutional investors and foreign investors For a long time, Viet Nam imposed restrictions on foreign ownership in domestically listed firms: up to 49% of the equity for the listed companies and up to 30% for the listed banks However, the Decree 60/2015/NĐ-CP which was promulgated by the government on 26 June 2015 and effective from 1 September

2015, has allowed firms except for certain cases to be hold by foreign investors up to 100%, unless otherwise stipulated by the firm’s rules and regulations Scrapping the cap of foreign ownership could have a positive impact on increasing liquidity in the market, attractting new investment capital to expand the business scales… However, it also may create risk for the market, i.e if the market has shocks, foreign investors may withdraw their capital, causing huge risk to investors as well as destablizing the macro economy

We conduct this research to examine whether the change in foreign ownership restriction has positive or negative impact on the price volatility or the rate of return and risk bearing

by investors if they invest in portfolios with different foreign ownership ratios after 2 years of amendment on foreign ownership ratios as set out in Decree No 60 Based on the analyses,

it is possible to look back at this regulation to address its reasonable and unreasonable issues to adjust in time in order to meet the needs of financial integration and stability This is

an urgent prerequisite since Vietnam stock market is on its way to increase liquidity for a market reclassification from the frontier to the emerging market

The remainder of the paper is organized as follows: Section 2 outlines theories and typically related studies; Section 3 discusses the research methodology; Empirical results are presented in Section 4 and Section 5 concludes the paper

2.Literature review

Prior to Fama-French’s three factor pricing model, some studies have shown that CAPM does not work well in practice These are studies by Banz (1981) or Basu (1983) Banz (1981)

is the first evidence-based study on the relationship between return and market price of listed stocks on NYSE, showing that stocks with lower market capitalization (small stocks) tend to have higher average returns than large stocks This research also conceded that CAPM is not suitable Basu (1983), on the other hand, examined the relationship between several factors and returns on the common stock of NYSE firms, including the earnings price ratios (E/P) and firm size (as measured by the market value of common stock) The results also reported that the common stock of small NYSE firms appeared to have higher returns than the common stock of large NYSE firms, meanwhile, stocks with high E/P had higher returns than stocks with low E/P Fama and French (1992) assessed the impact of market beta, size (measured

by the market value of common stock), book to market equity ratio (BE/ME), two leverage variables as the ratio of book assets to market equity (A/ME) and the ratio of book assets to book equity (A/BE), and the earnings price ratio (E/P) on stock return The authors acknowledged that even if the market beta is used on it own, discarding the other variables, the relationship between beta and return is significantly weak Meanwhile, the size and BE/ME have a close relation with return, even when combined with other variables Fama and French (1993) identified 5 common risk factors affecting returns on stocks and bonds; in which there are 3 stock-market factors, including an overall market factor and factors related to firm size and book-to-market equity (BE/ME) Fama and French (1995) observed whether there was a relationship between the behavior of stock prices and the size or the BE/ME ratio since

traditional theories suggest that stocks with higher BE/ME ratio typically have lower return whereas stocks with lower BE/ME ratio have higher return This research is developed by their previous one (1993), yet extended by using the

dividend to price ratio (D/P) The result suggested that the market factor, size and BE/ME ratio play a role in explaining stock returns Specifically, the size and BE/ME ratio helped to clarify the behavior of stock prices whereas other factors such as D/P ratio is not significant

By the same token, Pin Huang Chou, Robin K.Chou, and Jane Sue Wang (2004) questioned whether the size and BE/ME ratio have a significant effect on stock return and the result emphasized that predictability of the size and BE/ME generally decreases over time periods 1982-2001 and 1990-2001 respectively Yet, the result pointed out that the size still has meaningful value in January The relationship between the stock return and the size is negative In the recent work, Fama and French (2008) tested the anomalies in the asset pricing model by using research data from listed stocks on NYSE, AMEX and NASDAQ for the period 1963-2005 This research took into account the abnomalies such as profitability, asset growth rate, and explore the differences across micro, small and large groups The result indicated that there are asset growth anomalies only in small group in comparison with large group Companies with higher profitability and earnings tend to have higher abnormal return, yet there is still no evidence that companies with low earnings would have lower abnormal return Similarly, Tran and Nguyen (2012) examined the impact of the size on the return of listed stocks in Vietnam stock market, and discussed about ‘the risk of the size’ With the data collected for the period from 1/2007 to 12/2011, the authors figured out that the size is associated with the stocks’ return with the slope of greater than zero This findings challenge the work of earlier researchers and it is probably a characteristic of Vietnam stock market From another perspective, Weimin Liu (2006) studied the liquidity in the asset pricing model, in which liquidity proxy is the number of traded shares to the number of outstanding shares ratio, adjusted to nontrading days This work tested the asset pricing model by combining liquidity with three factor FF model (1993) The findings showed that the two factor model – comprising market and liquidity - explains quite well the fluctuations in return; whereas BE/ME variable in the Fama French three factor model is not significant in the pricing model In like manner, Lam, K and Tam Lewis (2011) investigated the rationality in asset pricing models in Hong Kong stock market for the period 1981-2004 The result proved that the Fama and French three factor model combined with liquidity (measured by the ratio of the number of traded shares to the number of outstanding shares) can be used to explained the return of listed stocks, meanwhile the Carhart four factor model (1997) could not Likewise, Nguyen Anh Phong (2016) developed the Fama French three factor model by adding liquidity, in which liquidity is measured by two different ways The author argued that when the liquidity was added, the risk-return measurement model becomes more effective than CAPM or the Fama French three factor model The Fama French five factor model is an extension of the Fama French three factor model with three anomalies are added, consist of issued stocks, advances, volatility, momentum.The Fama French five factor model performs better than the Fama French three factor model when applied for the left hand side portfolios (LHS) except for investment portfolios established from size and advances

Roger D Huang and Cheng-Yi Shiu (2009) applied Carhart model to evaluate the investment performance of foreign investors in Taiwan stock market This study is different from previous work in respect of examining factors which were assumed to affect the portfolio’s risk-return based on their foreign ownership ranking Stocks are divided into five portfolios ranked by foreign ownership from high to low The finding indicated that the return and risk of portfolios with high level of foreign ownership is higher than that of portfolios with low level of foreign ownership Recently, Söhnke M Bartram, John Griffin, and David Ng (2004, 2015) found evidence on the ‘foreign ownership effect’ promoted by active reallocations of global institutions as opposed to fund flows from end investors and the importance of foreign ownership linkages for international stock returns – that implied implications for international portfolio diversification

3.1 Research data

Data for this study were collected from Finpro and Thomson Reuters, including data of listed firms over the 2010 – 2017 period except for those in banking, securities, insurance and hedge funds sectors since they have their own financial reporting systems and regulations on foreign ownership as well Table 1 shows that the ratio of number of selected companies to number of total listed companies is very high, ensuring the reliability of the research Moreover, firms with book value of less than zero are also excluded

Table 1 Number of listed companies and number of selected companies

Year

Number of listed companies

Number of selected companies Percentage % 201

7

72 8

68 3

93.8 2 201

201

201

201

3

63 9

54 9

85.9 2 201

2

65 4

53 6

81.9 6 201

1

64 3

51 5

80.0 9 201

0

59 6

47 1

79.0 3

Source: State Securities Commission of Vietnam

3.2 Research model

The study aims at assessing the investment efficiency of investors in terms of risk and return, based on differences in foreign ownership ratio as mentioned in Roger D Huang and Cheng-Yi Shiu (2009) In addition, in developing and emerging markets like Vietnam stock market, liquidity plays an important role in explaining the risk- return profile of stock portfolios (Nguyen Anh Phong, 2014); therefore, in this study, we propose a research model to evaluate the investment performance in terms of risk and return as follows:

Rit – Rft = ai + bi(RMt – Rft) + si(RSMBt) + hi(RHMLt) + li(RLMHt) +

eit Where:

Rit :average returns of stock portfolios i, in which portfolios are classified into 5 categories

by foreign ownership ratio of listed companies, including R1, R2, R3, R4 and R5 portfolios R1

is the return of portfolio with 1/5 (or 20%) stocks having largest foreign ownership likewise R5

is the return of portfolio with 1/5 (or 20%) stocks having smallest foreign ownership Besides,

we also consider average returns of other categories, including: average returns on stock portfolio with large size and high book to market ratio (BH), average returns on stock portfolio with large size and medium book to market ratio (BM), average returns on stock portfolio with large size and low book to market ratio (BL), average returns on stock portfolio with small size and high book to market ratio (SH), average returns on stock portfolio with small size and medium book to market ratio (SM), average returns on stock portfolio with small size and low book to market ratio (SL)

RMt: average market return

RFt: risk free rate (interest rate on 1 year T-bill obtained from quoted price at the first day of each month, calculated on monthly basis)

RSMBt :the difference between average return on small portfolio and average return on large portfolio RHMLt: the difference between average return on high BE/ME portfolio and average return on low BE/ME

portfolio

RLMHt: the difference between average return on low liquidity portfolio and average return on high liquidity portfolio Liquidity is measured in two ways:

+ Liq1 is measured by the average trading value of shares each month (in million dong) + Liq2 is measured by the number of traded shares each month to the number of

outstanding shares ratio ai :the regression coefficient

bi, si, hi, li :the slope coefficients of portfolios

respectively eit: the error term

In estimated models using GMM method, we use I/V variable (instrumental variable) as the return of the previous time (Rt-1) Theoretically, using Rt-1is consistent with Fama’s statement

on rational expectation and efficient market hypothesis; because if the market is efficient, all information is reflected in price, then the return of the previous time is expected for the current time In addition, Hansen, Singleon (1982) and Cochrane (2000) adjusted the omega matrix to correct all common errors when using time series data, most commonly using Rt-1as the endogenous variable or I/V variable and still provide consistent and efficient estimations In this study, beside using the lagged (t-1) variables of R1 to R5 as I/V variables, we also use liquidity variable 2 (Rliq2) as I/V variable as liquidity 2 is measured by the number of traded shares each month to the number of outstanding shares ratio whereas liquidity 1 is measured

by the average trading value of shares each month Therefore, it is clearly that outstanding shares have an effect on trading value of shares

4.Research result

Table 2 Descriptive statistics

Source: Calculated based on data from Finpro and Thomson Reuters

Table 2 shows that portfolios with higher foreign ownership ratio tend to have higher average return: return on portfolio with the highest level of foreign ownership is 1.61% per month whereas return on portfolio with the lowest level of foreign ownership is 1.41% per month In terms of liquidity, the high liquidity portfolio has higher average return (5.14%) in contrast to the low liquidity portfolio with average return of 1.71% In terms of size, the average return of large-size portfolio is higher than the average return of small-size portfolio In terms of value, the average return of portfolio with low BE/ME is higher than the average return of high BE/ME Table 1 also states the big variation in variables, data seem to be non-stationary

Table 3 Stationarity

Testing

Source: Calculated based on data from Finpro and Thomson Reuters

Results from ADF (Augmented Dickey Fuller) test report that the computed absolute t-statistic values are all larger than the absolute critical value of 3.52 with a significant level of 1%; indicating that all variables are stationary This finding suggests that using the GMM method is reasonable, according to Jagannathan and Skoulakis (2002)

Table 4 Result regressions using GMM method

Dependent

variables

Alpha RM-RF1 RSMB RHML RLIQ1 R2 RMSE R1 4.00(*) 5.17(*) 0.33(*) -0.17 -0.34(*) 0.76 2.61 R2 1.41 2.07(***) 0.63(*) -0.44(*) -0.28(*) 0.81 2.40 R3 -0.06 0.35 0.82(*) -0.64(*) -0.24(*) 0.84 2.25

R5 3.18(**) 3.79(**) 0.86(*) -0.59(*) -0.16(*) 0.73 3.08

RBM 2.40(**) 3.47(**) 0.14(***) -0.53(*) -0.24(*) 0.57 2.38

RSH 1.5(***) 1.88(***) 0.91(*) 0.49(*) -0.21(*) 0.94 1.71 RSM 2.00 2.95(**) 1.35(*) -0.64(*) -0.26(*) 0.91 2.49 RSL 1.50 2.07(***) 0.99(*) -1.09(*) -0.18(*) 0.91 1.81

Source: Calculated based on data from Finpro and Thomson Reuters; (*), (**), (***) indicates the level of significance at the 1%, 5% and 10% respectively; endogenous variables include first lag variables of R1, R2, R3, R4, R5 and Liq2 variables

1 Note: R F is calculated as 10 year government bond yield on a monthly basis and interest rate is presented per month;

ME t = P t xS t ,in which: ME t is size at time t (in million dong), P t is price at time t and S t is outstanding shares at time t (calculated each month); the book to market equity ratio variable (BE/ME) is calculated by the following formula: (BE/ME) t = BE t-1 /ME t , in which: BE t-1 is the book value of equity Because this value is known only at the end of the fiscal year, the book value of equity for the preceding year (year t-1) is used for this year; returns on BH, BM, BL, SH,

SM, SL, SMB, HML portfolios are addressed based on studies of Fama-French (1992-1993-2012), Carhart (1997), Weimin

Lin (2006), Lam K và Tam Lewis(2011), and many others; R1, R2, R3, R4, R5 portfolios are average returns of portfolios sorted by different foreign ownership ratios from the 20% lowest to the 20% highest