• Journal of Intelligence and Information Systems
• /
• v.27 no.1
• /
• pp.65-82
• /
• 2021

Stock market investors are generally split into foreign investors, institutional investors, and individual investors. Compared to individual investor groups, professional investor groups such as foreign investors have an advantage in information and financial power and, as a result, foreign investors are known to show good investment performance among market participants. The purpose of this study is to propose an investment strategy that combines investor-specific transaction information and machine learning, and to analyze the portfolio investment performance of the proposed model using actual stock price and investor-specific transaction data. The Korea Exchange offers daily information on the volume of purchase and sale of each investor to securities firms. We developed a data collection program in C# programming language using an API provided by Daishin Securities Cybosplus, and collected 151 out of 200 KOSPI stocks with daily opening price, closing price and investor-specific net purchase data from January 2, 2007 to July 31, 2017. The self-organizing map model is an artificial neural network that performs clustering by unsupervised learning and has been introduced by Teuvo Kohonen since 1984. We implement competition among intra-surface artificial neurons, and all connections are non-recursive artificial neural networks that go from bottom to top. It can also be expanded to multiple layers, although many fault layers are commonly used. Linear functions are used by active functions of artificial nerve cells, and learning rules use Instar rules as well as general competitive learning. The core of the backpropagation model is the model that performs classification by supervised learning as an artificial neural network. We grouped and transformed investor-specific transaction volume data to learn backpropagation models through the self-organizing map model of artificial neural networks. As a result of the estimation of verification data through training, the portfolios were rebalanced monthly. For performance analysis, a passive portfolio was designated and the KOSPI 200 and KOSPI index returns for proxies on market returns were also obtained. Performance analysis was conducted using the equally-weighted portfolio return, compound interest rate, annual return, Maximum Draw Down, standard deviation, and Sharpe Ratio. Buy and hold returns of the top 10 market capitalization stocks are designated as a benchmark. Buy and hold strategy is the best strategy under the efficient market hypothesis. The prediction rate of learning data using backpropagation model was significantly high at 96.61%, while the prediction rate of verification data was also relatively high in the results of the 57.1% verification data. The performance evaluation of self-organizing map grouping can be determined as a result of a backpropagation model. This is because if the grouping results of the self-organizing map model had been poor, the learning results of the backpropagation model would have been poor. In this way, the performance assessment of machine learning is judged to be better learned than previous studies. Our portfolio doubled the return on the benchmark and performed better than the market returns on the KOSPI and KOSPI 200 indexes. In contrast to the benchmark, the MDD and standard deviation for portfolio risk indicators also showed better results. The Sharpe Ratio performed higher than benchmarks and stock market indexes. Through this, we presented the direction of portfolio composition program using machine learning and investor-specific transaction information and showed that it can be used to develop programs for real stock investment. The return is the result of monthly portfolio composition and asset rebalancing to the same proportion. Better outcomes are predicted when forming a monthly portfolio if the system is enforced by rebalancing the suggested stocks continuously without selling and re-buying it. Therefore, real transactions appear to be relevant.

• The Journal of the Korea Contents Association
• /
• v.19 no.9
• /
• pp.242-253
• /
• 2019

There has been a large literature on bank liquidity risk since the 2008 global financial crisis because liquidity risk was at the heart of the crisis. However, there is no study that investigates whether the level of investor protection influences liquidity risk-taking behavior of banks. Therefore, this study aims to explore the relationship between investor protection and liquidity risk as well as to provide policy implications. Using a panel dataset of commercial banks in 21 OECD countries, we found that strong investor protection encourages banks to take lower liquidity risk. Furthermore, this positive role of shareholder protection is more prominent during a crisis, implying that legal protection of investors plays an essential role in bank stability while market discipline is largely ineffective due to extensive government guarantees in turbulent times.

• Management & Information Systems Review
• /
• v.34 no.1
• /
• pp.65-80
• /
• 2015

In previous studies concerning turnover, they argue individual stock's turnover must be identical to market portfolio's turnover under one condition where 2 funds separation theorem holds. In this kind of world, all market participants hold and trade the same portfolio and this should be only market portfolio. If one's trading portfolio's shape is different from market portfolio's, this would mean he or she has an advantage over others in information and this kind of information would be private. In accordance with this theory, we develop a metric which measures how far one's trading portfolio from market's and name it as Stock Selection by Investor(SSI). We apply this measurement to the various types of investor groups classified as individual, institutional and foreign who participate in Korea stock market. To test the validity of measure, we regress price ratio on this measurement using SUR method. As a result, individual investor group shows large number in SSI, but the coefficient in regression is not significant and economically meaningless. In case of institutional investor group, the coefficient proves to be significantly negative. We can infer from this fact that their trading is somehow far from informed trading. Stock selection activity by foreign investor groups proves to be informed trading by showing significantly positive coefficient and the magnitude of coefficient is economically meaningful, especially in sell activity.

• The Journal of the Korea Contents Association
• /
• v.14 no.3
• /
• pp.374-384
• /
• 2014

In this paper, characteristics of transactions by investors were examined based on the relationship between South Korea's stock market trends and the amount of net purchasing by investors. The study period is from January of 2004 to December of 2011, a total 1,991 days on 96 months. Data used for correlation and regression analysis include the value of the KOSPI index at the end of each month, the monthly net purchase amount of each of the groups, as well the daily volume, the daily price. In this study, the long-term phase of the market divided by refining. and each of the investment position of invest group was investigated. As a result, foreign investors are a net selling position when market was rising phase of the tertiary. And private investors were a net short positions when the market was decline phase of the tertiary. Regardless of the flow changes, the private investors had opposite position to the flow of the mark, also they had opposite position to the position of the foreign investors.

• Venture DIGEST
• /
• s.108
• /
• pp.38-39
• /
• 2007

벤처기업은 금융기관 등으로부터 자금을 차입하거나 투자를 유치하는 방법으로 외부자본을 이용하게 된다. 자금차입 기법에는 담보대출이나 신디케이트론 등이 있는데, 마땅한 담보자산을 가지지 못한 벤처기업으로서는 금융기관으로부터 차입을 하는 데에도 한계가 있기 마련이다. 따라서 벤처캐피탈 등 기관투자자로부터의 투자 유치는 벤처기업의 자금조달에 매우 효율적이면서 적절한 자금조달방법이 될 수 있다. 본 호에서는 벤처기업의 투자 유치 시 가장 보편적으로 이용되고 있는 전환사채 및 전환상환우선주와 관련된 법적 쟁점에 대해 살펴 보고자 한다.

• Management & Information Systems Review
• /
• v.31 no.3
• /
• pp.21-46
• /
• 2012

This paper attempts to offer an effective strategy of hedge fund based on trade probability control in the futures market. By using various technical indicators, we create an association rule and transforms it into a trading rule to be used as an investment strategy. Association rules are made by the combination of various technical indicators and the range of individual indicator value. Adjustments of trade probabilities are performed by depending on the rule combinations and it can be utilized to establish an effective investment strategy onto the risk management. In order to demonstrate the superiority of the investment strategy proposed, we analyzed a profitability using the futures index based on KOSPI200. Experiments results show that our proposed strategy could effectively manage and response the dynamics investment risks.

• The Journal of Small Business Innovation
• /
• v.19 no.1
• /
• pp.59-84
• /
• 2016

Using an international setting, this study investigates the relation between cash holdings and financial reporting quality, measured by accruals quality. Empirical results show that the balance of cash holdings is positively related to the opacity of financial reporting in non-U.S. international markets. The relation becomes stronger as the strength of investor protection increases, implying that precautionary motives, instead of agency motives, drive the increase of cash holdings of opaque firms. In addition, the positive relation is stronger for discretionary accruals quality. The decomposition of the aspects of investor protection shows that public enforcement through regulation authorities is the main driver of the positive relation between cash holdings and the opacity of financial reporting.

• The Korean Journal of Financial Management
• /
• v.20 no.2
• /
• pp.127-150
• /
• 2003

This study analyzes how capital market comovement can affect investors' decision making. We first analyze time-varying correlation coefficient between stock indices of U.S.A. and Korea. and then, using our empirical results, attempt to draw implications on investors' behavior. We find that the tendency of comovement between Korea and U.S.A. equity returns has considerably increased after the financial crisis of late 1997. Through the analysis of investors' behavior, we find that foreign investors, contrary to ITC's (Investment Trust Company) and individual investors, buy more shares in Korean markets as American stock prices go up. Foreign investors employ dynamic hedging strategy and give more weight on global economic factors than domestic ones. Our empirical results as a whole imply that investment behavior of foreign investors is most closely related to comovement of U.S.A. and Korea capital markets.

• International Area Studies Review
• /
• v.16 no.3
• /
• pp.239-266
• /
• 2012

The purpose of this paper is to suggest desirable improvement for KRX derivatives market plagued with many problems in spite of its world level of quantitative growth. In order to try to find desirable improvement for KRX derivatives market which has many problems like that, I suggest various ways of improvement for regulatory system in the future in terms of behavioral regulation for investor protection. First of all, in order to relieve speculative tendency of trading, KOSPI200 option market with ATM-oriented option trading needs to be induced from the market in which OTM-oriented option is now trading. So discount or exemption of brokerage fee for ATM trading and the introduction of market-maker for ATM type can be considered. For the protection of individual investors, we suggest feasible plans such as differential regulation between professional and individual investors, consolidation of basic deposit management, and enlargement of opportunities for risk management education & simulation trading.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.17 no.4
• /
• pp.45-55
• /
• 2022

Accelerator is a private investment institution that provides startups with comprehensive solutions to solve various difficulties such as startup facilities, funds, commercialization, securing a market etc. In addition to the role of an investor as a new startup support model, accelerators have contributed much to improvement of business ability of startups through intensive mentoring. Considering that previous studies gave weight to the determinants of investment from the perspective of investors, this study made a comparative analysis on the relative importance of determinants of investment in startups among accelerators, investors and entrepreneurs through the method of AHP. Results show that accelerators and investors regard "managerial characteristics" of startups as of the highest importance, whereas entrepreneurs think that "market characteristics" of startups are the most important. The result stems from an empirical judgment from the perspective of investors that success of startups depends on the ability of entrepreneur, and it is considered that investors evaluated marketability of startups as the most important factor in consideration of investment payback period. The result is similar to the result of previous studies on the determinants of investment determinants of angel investors and venture capitals. This paper is expected to make a contribution to the advancement of investment decision-making model for accelerators to discover startups with high possibility to grow and achieve more in incubation and investment.