Browsing by Author "van Rensburg, Paul"

Now showing 1 - 14 of 14
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    Open Access
    A time-series and cross-sectional momentum strategy: Dual momentum applied from a South African perspective
    (2022) Fuchsloch, Michael; van Rensburg, Paul
    Fama and French (2008, p.1654) referred to momentum as a “premier market anomaly”. The momentum effect has been nearly universally observed across all asset classes globally (Asness, et al., 2013). This research paper further explores momentum and replicates the dual momentum strategy proposed by Antonacci (2014) within a South African context. Dual momentum combines time-series and cross-sectional momentum in pursuit of enhanced risk adjusted returns. The strategy is constructed using tradeable indices in order to minimise transaction costs. This study investigates the dual momentum strategy applied to the JSE Top 40 index. The strategy also includes two indexes which stay constant, the MSCI ACWI index for offshore exposure and the STeFI index which serves as an alternative proxy investment and acts as a safe haven during economic downturn. In addition, this study investigates two variations of the core strategy which include shortening the look-back period and lowering the strategy's threshold. Furthermore, and supplementary to the core strategy, dual momentum is applied to several South African sector indexes. Followed by a second supplementary section where dual momentum is applied to a pool of indexes where only the top performing index is used over a specific period in time. The results of the performance analysis of the dual momentum strategy over the sample period illustrates the strategy's ability to generate superior risk adjusted returns, lower standard deviations, lower maximum drawdowns, and yields significant positive alpha. Thus, the core dual momentum strategy and focal point of this study, validates the strategy within a South African context. However, the results of the variations and both supplementary sections display a vast range in underperformance. This highlights the dual momentum strategy's inability to adequately cope with high volatility. During periods of high volatility, the strategy tends to struggle which is also the case with the core strategy and most other momentum strategies. Therefore, the two variations and supplementary strategies do not manage to improve the core dual momentum strategy.
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    An investigation into South African property unit trusts: do active managers add value to investors?
    (2020) Rickens, Carl; van Rensburg, Paul
    Active vs passive management is a central debate within asset management, with active managers promising superior market beating performance after fees through their superior knowledge and stock selection. This study investigates the performance of 34 South African property unit trusts over multiple periods between 2005 and 2018. Fund performance was evaluated using three risk-adjusted measures, namely the Sharpe ratio, information ratio and Jensen's alpha, in order to determine whether there is significant outperformance amongst the funds. The benchmark used to compare performance was the South African Listed Property index (SAPY), which is the most common and well established proxy for the South African property market. The sample was divided into three periods, long term 2005-2018, medium term 2008-2018 and short term 2015-2018. In all periods, outperformance of active funds were shown to be inconclusive, with only a small number of funds showing significant positive alphas and significantly high Sharpe and information ratios. A small number of funds achieved outperformance across multiple periods. On average significant outperformance was uncommon and inconsistent. Furthermore, a number of funds achieved significant underperformance over multiple periods, with inferior risk-adjusted returns and alphas compared to the benchmark. However, the volatility of fund returns were shown to be less than the benchmark on average in all periods, indicating that active managers were able to reduce volatility compared to the benchmark. In the more recent short term period, performance of the active funds were especially low with many negative alphas' present. The best performing fund across multiple periods was shown to be a risk parity portfolio of property stocks, which achieved significantly higher returns whilst having lower volatility than the benchmark and other funds. Ultimately the results suggest that active managers in the sector do not provide sufficient evidence for outperformance. Hence investors are better of making use of passive indices or a risk parity portfolio if they are looking for exposure to South African listed property. This is in line with other international studies which have also found that active management in the property industry does not provide significant and consistent outperformance. These results provide useful insight to property investors in South Africa and contribute to the debate between active vs passive management within the financial literature.
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    An Investigation into The Predictive Power of Overnight Gaps on The Johannesburg Stock Exchange
    (2023) de Jager, Johannes; van Rensburg, Paul
    Stock market gaps occur nearly every day, yet very little is known about their influence on subsequent pricing behaviour, particularly in developing economies like South Africa. The aim of this research is to comprehensively identify and analyse the relationship between overnight price gaps and subsequent intraday returns for publicly traded South African companies. These theoretical findings will also be applied practically, with a simulated trading strategy created and tested based on the theoretical and statistical findings. The primary method of identifying the underlying relationships at play is a collection of multiple linear and multiple logistic regression models, created using data spanning 20 years and 371 companies and split into training and testing sections to ensure accurate and bias-free results. The robust set of statistical tests and analyses performed indicates a persistent and highly significant inverse relationship that exists between large overnight gaps and subsequent intraday returns. This significant relationship was also applied to a very successful mean-reversion based trading strategy, with a sustained average annual outperformance of the JSE AllShare Index observed under even the highest transaction costs of 1.3% per trade. At the lower transaction cost level associated with CFD trading, an average annual outperformance of 166% was recorded. The theoretical and practical implications of these findings are in stark contrast to the widely accepted efficient market hypothesis and provide compelling new evidence of the exploitable nature of a relatively under researched market anomaly created by the inefficiencies associated with overnight price gaps. These results also pave the way for further analyses of gap behaviour, and collectively these findings add new and meaningful results to the body of knowledge on market anomalies.
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    An investigation into the style and asset class adjusted performance of South African multi-asset funds
    (2019) Richardson, Luke A.C.; van Rensburg, Paul
    Purpose: This study examines 26 large and established South African multi-asset unit trusts in order to determine their style and asset class exposure over time. The objective is to ascertain whether South African multi-asset fund managers can realise outperformance, that exceeds what can be realised through exposure to representative, investable, style and asset class indices. Such an analysis assists in identifying unit trust manager skill, but a further consideration is how to combine unit trusts in a suitable manner, to this end portfolio construction tools are utilised to meet illustrative client objectives in a multi-asset context. Methodology: This study uses monthly total return time series for several investable style and asset class indices as well as South African multi-asset unit trust monthly total return time series. Where historical data permits, the period under investigation is from 1 January 2003 to 30 June 2018. Style and asset class exposure is determined using the Returns Based Style Analysis (RBSA) of Sharpe (1992) applying a 24-month rolling window approach. Findings: The equity style exposures estimated using RBSA provide evidence that on average the value style was dominant across the multi-asset high equity unit trusts examined. For the multi-asset low equity unit trusts examined the low volatility style was dominant. Moreover, a large proportion of the variability in returns of many multi asset unit trusts, can be explained by exposure to style and asset class indices. Consequently only 3 out of the 15 multi-asset high equity unit trusts analysed, could realise performance in excess of their custom style and asset class benchmark. As only a limited number of these unit trusts could demonstrate superior security selection ability the implication is that many asset managers stand to be disrupted by lower cost products that provide similar style and asset class index exposure. Originality/Value: Much research has been conducted into the style exposures of SA general equity funds. However, to the author’s own knowledge this is the first study to apply RBSA in a performance context to multi-asset unit trusts, under the new ASISA classification standards. The benefits of portfolio construction tools such as portfolio simulation and the ‘Risk Budgeting’ approach are also discussed and applied in a multi-asset context.
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    Artificial Neural Networks in Stock Return Prediction: Testing Model Specification in a Global Context
    (2020) Buxton-Tetteh, Naa Ayorkor; van Rensburg, Paul
    This research investigates whether artificial neural networks which make use of firm specific fundamental and technical factors can accurately predict the returns of a sample of several large-cap stocks from various markets across the globe. This study also explores which hidden layer configuration leads to the best network predictive performance. Furthermore, this research identifies which firm-specific factors predominantly influence the predictions made by the artificial neural networks. Five artificial neural networks are designed, trained and tested on a sample of 161 stocks from the Russell 1000 and the S&P International 700 stock indices. The investigation period extends over a 166-month period from January 2001 to October 2014 with a 70:30 split for training and testing subsamples respectively. Eighteen firm-specific factors, based on prior research about the presence of style effects or anomalies on the cross-section of global equity returns, are used as the input variables of the artificial neural networks to forecast one-month forward returns of all the stocks in the sample. The five artificial neural networks investigated in this research differed in hidden layer size. Specifically, the number of hidden neurons examined were three, nine, 13, 18 and 30. All five networks train significantly well, with each network's training error indicating a good model fit. Each network also achieves the desirable information coefficient of 0.1 between its predicted returns and the actual returns in the training sample. It is interestingly discovered that network performance generally improves as the number of hidden neurons in the hidden layer increases until a specific point, after which network performance weakens. In the context of avoiding overfitting, the best-trained network in this research is that with 13 neurons in its hidden layer. This is the primary network used for the out-of sample testing analysis. This network achieves an average prediction error magnitude of approximately 7% and an information coefficient of 0.05 during out-of-sample testing. These results underperform their respective benchmarks moderately. However, further analyses of the network's performance suggest an overall poor out-of-sample predictive ability. This is illustrated by a significant bias and a considerably weak relationship between the network's predicted returns and the actual returns in the testing sample. Global sensitivity analysis reveals that growth style effects, particularly, the capital expenditure ratio, return on equity, sales growth, 12-month percentage change in non-current assets and six-month percentage change in asset turnover were the most persistent factors across all the ANN models. Other significant factors include the 12-month percentage change in monthly volume traded, three-month cumulative prior return and one-month prior return. An unconventional result of this analysis is the relative insignificance of the size and value style effects.
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    Constructing low cost core-satellite portfolios with multiple risk constraints: practical applications to Robo advising in South Africa using active, passive and smart-beta strategies
    (2020) Smith, Jacques; van Rensburg, Paul
    Risk and tracking error budgeting was originally adopted by large institutional investors, including pension funds, plan sponsors, foundations, and endowments. More recently, risk and tracking error budgeting have gained popularity among financial advisors, multi-managers, fund of funds managers, high net worth individuals as well as retail investors. These techniques contribute to the portfolio optimisation process by limiting the extent to which a portfolio can deviate from its benchmark with regards to risk and tracking error. This is an ambitious paper that attempts to determine the optimal strategy to practically implement risk and tracking error budgeting as a portfolio optimisation technique in South Africa. This study attempts to bridge the gap between active, passive, and smart-beta investment management styles by introducing a low-cost portfolio construction technique, for core-satellite portfolio management, which contributes to the risk and tracking error budgeting process. Core-satellite portfolios are designed to expose the portfolio to a low-cost primary “core” consisting of passive and enhanced index funds, thus systematic risk “beta”, limiting the tracking error of the portfolio. The secondary “satellite” component is allocated to active and smart-beta managers to exploit expected excess return “alpha”. The primary aim of this research is to construct a rule-based product range of core-satellite portfolios called “replica portfolios”. The product range builds on the foundation of the Association for Savings & Investments South Africa (ASISA) framework. The study identifies three “target portfolios” from ASISA's framework, namely (1) High Risk: SA General Equity, (2) Medium Risk: SA Multi-Asset High Equity and (3) Low Risk: SA Multi-Asset Low Equity. Through this framework, active managers from each category are shortlisted using a Sharpe and Information Ratio filter. A secondary filtering technique, namely Returns Based Style Analysis (RBSA) is used to determine the style, R-squared and alpha-generating ability of active managers versus the passive asset classes and style indices they seek to replicate. Applying Euler's theorem for homogenous functions, we decompose the risk of the coresatellite portfolio into the risk contributed by each of its components. The primary mandate of the core-satellite portfolios in the product range is to allocate risk and tracking error efficiently across several investment management styles and asset classes in order to maximise returns while remaining within the specified risk parameters. iii The results highlighted that active managers, after fees, predominantly failed to outperform their benchmarks and passive building blocks, as identified through RBSA over the sample period (October 2009 – September 2019). However, only a small number of active managers generated superior risk-adjusted returns and were included in the core-satellite range of products. This study recommends to investors that they exploit the “hot-hands effect” by investing in specialised, benchmark agnostic active managers who consistently produce superior risk-adjusted returns. By blending active, passive and smart-beta strategies, investors are exposed to less total risk, less risk per holding and a lower tracking error. The three coresatellite portfolios developed in this study generated absolute and risk-adjusted returns that are more significant than their active and passive counterparts. Fee arbitrage was derived through the range of core-satellite products, resulting in tangible alpha over the sample period. The study encourages investors to use smart-beta strategies alongside active and passive funds since it improves Sharpe and Information ratios while enhancing the original portfolio's characteristics.
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    ESG and corporate financial performance: evidence from JSE listed firms
    (2022) Muzanya, Shelton; van Rensburg, Paul
    Business is an incredible social construct of the world, consisting of firms that are part of and arise from society. However, businesses have come under increasing scrutiny from internal and external stakeholders over sustainable business practices. A sustainable business model creates a balance between integrity, equity and financial prosperity, the so-called triple-bottom-line. Environmental, social and governance issues (ESG) have become the modern-day proxy for sustainable business practices. The relationship between sustainable business practices and corporate financial performance is a relatively new but prominent area of research in practice and academia in South Africa. This study explores the relationship between ESG disclosure performance and the corresponding corporate financial performance (CFP) for 70 sampled firms listed on the Johannesburg Stock Exchange (JSE) between the periods 2011 and 2019. In line with international and South African research, ESG in its composite and disaggregated form was considered against a select number of CFP metrics. Select accounting-, market- and qualitybased CFP metrics were considered. Quantitative research methods were employed, using panel regression models to investigate the ESG-CFP relationship where ESG was the independent variable while the CFP metrics were individually considered as the dependent variables. All CFP data was obtained from Bloomberg and Bloomberg's proprietary ESG scores were used. This study finds a statistically significant negative relationship between ESG and the selected CFP metrics. Upon disaggregating the ESG scores, it was evident that the E- and S-scores were also significantly and negatively related to the CFP metrics whilst the G-score was positively related to CFP, but it was not statistically significant. The empirical evidence suggests that over a nine-year investment horizon, higher ESG disclosure performance detracts from firm fundamental and market performance. Further interpretation of the results in conjunction with the literature may suggest that ESG ought to be seen as an insurance policy against excessive underperformance during volatile periods and not a CFP enhancer. Therefore, being “over-insured with ESG” may lead to underperformance.
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    Modelling the long-and-short run dynamics of share price movements in the resource sector
    (2005) Davids, Megan; van Rensburg, Paul
    [page 49 missing] This paper involves the development and estimation of various statistical models that possess significant explanatory power in predicting future returns of resource shares. Models were constructed for IMPLATS, HARMONY, GOLDFIELDS, SASOL and SAPP!. Significant long-term relationships were found between company share price, earnings per share, dividends per share, commodity price and interest rates. The technique of co-integration permits these non-stationary economic variables to be linked by a stable long-term equilibrium relationship. For each co-integrating relationship an error correction model is developed to correct for short-term disequilibrium. The relationship between co-integration and error correction models is further extended to forecast future returns of share prices. A one-month rolling window forecasting method was implemented to forecast future returns of shares over one, two and three months respectively. Findings suggest that these results could be of considerable significance when making bets on a diversified portfolio of investments.
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    Outsider trading: trading on twitter sentiment
    (2022) Stevens, Joshua; van Rensburg, Paul
    This study aims to establish if a relationship between the investor sentiment generated from social media posts, such as Tweets, and the return on securities exists. If a relationship exists, one would be able to obtain an informational advantage from public information and outperform the market on a risk-adjusted basis. This would give the “outsider” information processed the predictive power of insider information, hence the title of the paper. The study makes use of Bloomberg's social activity data, which through natural language processing, allows for investor sentiment to be obtained by analysing a combination of Twitter and Stock Twits posts. This paper makes use of a three-prong approach, firstly examining if investor sentiment is a predictor of next-day returns. Next, an event study methodology is used to examine the optimal holding period, which can further be expanded to test market efficiency. Lastly, this paper considers the asymmetric risk aversion as outlined by Kahneman and Tversky (1979). Results show that there is little to no correlation between sentiment and next day returns. There is evidence for a multi-day holding period being optimal but statistically insignificant and there is no evidence found for asymmetric risk aversion.
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    Short Interest and the Cross-Section of S&P500 Share Returns
    (2022) Cumming, Kyle; van Rensburg, Paul
    This study aims to investigate the cross-sectional relationship between short interest and excess returns of the constituent securities of the Standard and Poor's 500 Index on a monthly basis. Short interest data is defined in relation to both trading volume and equity float for an 84-month period between January 2015 and December 2021 to examine the expected negative relationship. The use of the Fama-Macbeth (1973) method produces mixed empirical findings. The results of the short interest ratio do not support the findings of prior research, finding no significant relationship between the two variables. The short float ratio, however, produces a significantly positive relationship at the 10% level, supporting the “contrarian view”. An increase in the short float ratio of 1% leads to a 19.6 basis point increase in excess return in the subsequent month. Overall, our results for the short interest ratio support the efficient market hypothesis. In contrast, the short float ratio serves as a bullish indicator.
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    Testing the Long-Term Profitability of the Short-Term Reversal Strategy
    (2019) Tsiu, Matsepe Modikeng Theodore; van Rensburg, Paul
    The purpose of this investigation was to test the theoretical possibility of an investor earning a positive cash return from the activities of the stock market despite effectively holding no position at all in said market. The sample data were the daily returns for the shares of the 780 companies listed on the NASDAQ and the New York Stock Exchange (“NYSE”), which fell within the top 500 listed companies by market capitalisation between 1 January 2005 and 31 December 2017. The reversal strategy’s performance was evaluated using portfolios constructed as quantiles of 100 or 500 shares, respectively, where the investor had the option of implementing the reversal strategy immediately after an information-gathering period closed or a day thereafter. The time intervals used were 1 January 2005 to 29 September 2008 (the day the Dow Jones Industrial Average crashed by 777.68 points), 29 September 2008 to 31 December 2017 and 1 January 2005 to 31 December 2017. Of the 1000 portfolios tested in each time interval, at least 416 had positive average returns in every time interval. Of the portfolios that had positive average returns over the time intervals, at least 66 had statistically significant average returns in every time interval. The best-performing portfolio for the entire sample period was a combination of the best-performing pre-crash and post-crash portfolios - an investor who held that portfolio realised a cumulative return of approximately $61.39 for every $1 invested. The conclusion was that it was theoretically possible for an investor to earn a positive cash return from the market’s activities despite effectively holding no position at all in the market. Consequently, it was concluded that the strong form of Fama’s (1970) Efficient Market Hypothesis was disproved. Future research should include out-of-sample tests, tests that include restrictions on short selling and tests that consider the impact of trading costs on portfolio performance, to render the conclusions of this investigation more practically applicable to investors.
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    The Determinants of the Financial Performance of Insurance Companies in Mauritius
    (2020) Appiah, Emelia; van Rensburg, Paul
    The study examines the effects of internal factors, made up of firm specific variables, and the external factors, consisting of industry and macroeconomic variables, on the financial performance of insurance companies in Mauritius. In particular, the study investigates the impact of firm size, leverage, gross written premiums, reinsurance, combined ratio, market concentration, foreign exchange, inflation and GDP growth on the profitability of insurers in both the life and the nonlife markets. Profitability was proxied by return on assets (ROA) and the underwriting profit ratio (UWPR). The study employs an unbalanced panel data sample of twenty non-life and seventeen life insurers from 2008 to 2016, with one hundred and twenty-two (122) non-life and ninety-eight (98) life firm-year panel observations obtained from the Financial Services Commission (FSC) of Mauritius. The models were estimated using the sandwich estimator by White, (1980) and Eicker, (1963) within pooled OLS, fixed and random effects panel estimation techniques. The findings show that, a unit increase in the combined ratio and leverage of life insurers impact negatively on the return on assets (ROA), while an increase in reinsurance dependence and firm size impact underwriting profit ratio positively. In the non-life sector, the findings show that insurance companies' profitability is positively impacted by increases in the combined ratio and gross written premium, while market concentration and foreign exchange negatively impacted non-life insurers' profitability. The findings of the study help us to understand firm pricing behaviour within the insurance industry and help to protect consumer interests in the pricing of policies. The findings also have implications on the growth strategies and risk management activities of insurance companies in Mauritius.
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    The Impact Of Divestitures (Spin-offs And Sell-offs) Announcements On The Share Price Performance Of Parent’s Companies: South African Listed Companies
    (2019) Oyedotun, Ibukun; van Rensburg, Paul
    This thesis is based on the empirical examination of the impact of divestiture announcements, with a focus on spin-off and sell-off transactions, on the share performance of parent companies listed on the Johannesburg Stock Exchange (JSE) in South Africa. The sample of the study for spin-off consisted of 36 companies while that of sell-off transactions consisted of 41 companies listed on JSE for deals that were announced and concluded from 2006 to 2016. The cumulative average abnormal returns for the parent companies were calculated using the event study methodology over the entire event window. Abnormal returns were calculated using the two-factor APT model approach. The cumulative average abnormal returns significance was tested using the t-test. Thereafter, the average abnormal returns and cumulative average abnormal returns were compared over the event window for the pre and post announcement period. A comparison was also made between spin-off and sell-off transactions over the entire event window (-30, +30). Three key results were established, the first being that, spin-off transactions generate positive abnormal returns while sell-off transaction generate negative abnormal returns. Second, it is clear that there were significant positive cumulative average abnormal returns for postannouncement returns for spin-off transactions while the post-announcement returns for sell-off transactions generated a negative cumulative average abnormal returns. Thirdly, I compared the two form of divestiture (spin-off and sell-off transactions) and discovered that there appears to be significant evidence that the CAAR for spin-off transactions are higher than the CAAR for sell-off transactions.
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    The impact of macroeconomic variables on the performance of selected African stock markets
    (2021) Epalanga, Amarildo; van Rensburg, Paul
    This dissertation investigates the impact of macroeconomic variables on the performance of African stock markets, focusing on Egypt, Mauritius, and South Africa during the period 2009– 2019. This dissertation employed the multiple linear regression model and the Granger causality test to ascertain the impact of these factors. For each country, the stock market index was used as a dependant variable while interest rates, inflation rate, money supply, exchange rate, gold price, and oil price were used as independent variables. The results from the country-specific models varied widely from country to country. The heterogeneity of the results may be explained by differences in economic fundamentals between the countries, for example, market depth, market size, and liquidity. The model showed that interest rate, which is inversely related to stock prices, isthe only significant variable in explaining stock prices in Egypt. In Mauritius, it wasfound that only three factors significantly affect stock prices, namely, exchange rate, gold price, and inflation. A depreciation of the Mauritius Rupee to the USD and an increase of the gold prices decrease stock prices in Mauritius, whilst the effect of inflation was found to be positive. In South Africa, results showed that inflation, money supply, and oil prices significantly affect stock prices in the Johannesburg Stock Exchange (JSE). However, unlike for Mauritius (where inflation has a positive impact), in South Africa, its effect is negative. By contrast, money supply and oil prices were found to impact the JSE stock prices positively. Against the backdrop of these findings, this dissertation encourages the governments and policy makers in emerging markets to consider stabilising the macroeconomy to create a conducive environment for stock market development. The Granger causality test reveals that stock prices can be used to predict oil prices in Egypt. In contrast, the South African data suggests no causal relationship between macroeconomic factors and stock prices. Finally, the same test in Mauritius shows that money supply can be used to predict stock prices, and stock prices can be used to forecast gold prices and exchange rates.