Policy impacts on Vietnam stock markets: a case of anomalies and disequilibria 2000-2006

Vietnam launched its first-ever stock market, named as Ho Chi Minh City Securities Trading Center (HSTC) on July 20, 2000. This is one of pioneering works on HSTC, which finds empirical evidences for the following: Anomalies of the HSTC stock returns through clusters of limit-hits, limit-hit sequences; Strong herd effect toward extreme positive returns of the market portfolio;The specification of ARMA-GARCH helps capture fairly well issues such as serial correlations and fat-tailed for the stabilized period. By using further information and policy dummy variables, it is justifiable that policy decisions on technicalities of trading can have influential impacts on the move of risk level, through conditional variance behaviors of HSTC stock returns. Policies on trading and disclosure practices have had profound impacts on Vietnam Stock Market (VSM). The over-using of policy tools can harm the market and investing mentality. Price limits become increasingly irrelevant and prevent the market from self-adjusting to equilibrium. These results on VSM have not been reported before in the literature on Vietnam’s financial markets. Given the policy implications, we suggest that the Vietnamese authorities re-think the use of price limit and give more freedom to market participants.

The Vietnam's Transition Economy and Its Fledgling Financial Markets: 1986-2003

In this paper, we analyze the context of Vietnam’s economic standings in the reform period. The first section embarks on most remarkable factors, which promote the development of financial markets are: (i) Doi Moi policies in 1986 unleash ‘productive powers’. Real GDP growth, and key economic indicators improve. The economy truly departs from the old-style command economy; (ii) FDI component is present in the economy as sine qua non; a crucial growth engine, forming part of the financial markets, planting the ‘seeds’ for its growth; and (iii) the private economy is both the result and cause of the reform. Its growth is steady. Today, it represents a powerhouse, and helps form part of the genuine financial economy. A few noteworthy points found in the next section are: (i) No evidence of financial markets existence was found before Doi Moi. The reform has generated a bulk of private-sector financial companies. New developments have roots in the 1992-amended constitution (x3.2); (ii) The need to reform the financial started with the domino collapse of credit cooperatives in early 1990s. More stress is caused by the ‘blow’ of banking deficiency in late 1990s; and (iii) Laws on SBV and credit institutions, and the launch of the stock market are bold steps. Besides, the Asian financial turmoil forces the economy to reaffirm its reform agenda. Our findings also indicate, through empirical evidences, that economic conditions have stabilized throughout the reform, thanks to the contributions of the FDI and private economic sector. Private investment flows continue to be an eminent factor that drives the economy growth.

Essays on Vietnam’s Financial Reforms: Foreign Exchange Statistics and Evidence of Long-Run Equilibrium

In this paper, we examine exchange rates in Vietnam’s transitional economy. Evidence of long-run equilibrium are established in most cases through a single co-integrating vector among endogenous variables that determine the real exchange rates. This supports relative PPP in which ECT of the system can be combined linearly into a stationary process, reducing deviation from PPP in the long run. Restricted coefficient vectors ß’ = (1, 1, -1) for real exchange rates of currencies in question are not rejected. This empirics of relative PPP adds to found evidences by many researchers, including Flre et al. (1999), Lee (1999), Johnson (1990), Culver and Papell (1999), Cuddington and Liang (2001). Instead of testing for different time series on a common base currency, we use different base currencies (USD, GBP, JPY and EUR). By doing so we want to know the whether theory may posit significant differences against one currency? We have found consensus, given inevitable technical differences, even with smallerdata sample for EUR. Speeds of convergence to PPP and adjustment are faster compared to results from other researches for developed economies, using both observed and bootstrapped HL measures. Perhaps, a better explanation is the adjustment from hyperinflation period, after which the theory indicates that adjusting process actually accelerates. We observe that deviation appears to have been large in early stages of the reform, mostly overvaluation. Over time, its correction took place leading significant deviations to gradually disappear.

Analyses on Gold and US Dollar in Vietnam's Transitional Economy

This paper looks into economic insights offerred by considerations of two important financial markets in Vietnam, gold and USD. In general, the paper focuses on time series properties, mainly returns at different frequencies, and test the weak-form efficient market hypothesis. All the test rejects the efficiency of both gold and foreign exchange markets. All time series exhibit strong serial correlations. ARMA-GARCH specifications appear to have performed well with different time series. In all cases the changing volatility phenomenon is strongly supported through empirical data. An additional test is performed on the daily USD return to try to capture the impacts of Asian financial crisis and daily price limits applicable. No substantial impacts of the Asian crisis and the central bank-devised limits are found to influence the risk level of daily USD return.

Evidence for distinct dehydrogenase and isomerase sites within a single 3β-hydroxysteroid dehydrogenase/5-ene-4-ene isomerase protein

Complementary DNA encoding human 3β-hydroxysteroid dehydrogenase/5-ene-4-ene isomerase (30-HSD) has been expressed in transfected GH4C1 with use of the cytomegalovirus promoter. The activity of the expressed protein clearly shows that both dehydrogenase and isomerase enzymatic activities are present within a single protein. However, such findings do not indicate whether the two activities reside within one or two closely related catalytic sites. With use of [3H]-5-androstenedione, the intermediate compound in dehydroepiandrosterone (DHEA) transformation into 4-androstenedione by 3β-HSD, the present study shows that 4MA (N,N-diethyl-4-rnethyl-3-oxo-4-aza-5α-androstane-17β-carboxamide) and its analogues inhibit DHEA oxidation competitively while they exert a noncompetitive inhibition of the isomerization of 5-androstenedione to 4-androstenedione with an approximately 1000-fold higher Ki value. The present results thus strongly suggest that dehydrogenase and isomerase activities are present at separate sites on the 3β-HSD protein. In addition, using 5α-dihydrotestosterone (DHT) and 5α-androstane-3β,17β-diol as substrates for dehydrogenase activity only, we have found that dehydrogenase activity is reversibly and competitively inhibited by 4MA. Such data suggest that the irreversible step in the transformation of DHEA to 4-androstenedione is due to a separate site possessing isomerase activity that converts the 5-ene-3-keto to a much more stable 4-ene-3-keto configuration. © 1991 American Chemical Society.