Quadratic minimization with portfolio and intertemporal wealth constraints

We address a problem of stochastic optimal control motivated by portfolio optimization in mathematical finance, the goal of which is to minimize the expected value of a general quadratic loss function of the wealth at close of trade when there is a specified convex constraint on the portfolio, together with a specified almost-sure lower-bound on intertemporal wealth over the full trading interval. A precursor to the present work, by Heunis (Ann Financ 11:243–282, 2015), addressed the simpler problem of minimizing a general quadratic loss function with a convex portfolio constraint and a stipulated almost-sure lower-bound on the wealth only at close of trade. In the parlance of optimal control the problem that we shall address here exhibits the combination of a control constraint (i.e. the portfolio constraint) together with an almost-sure intertemporal state constraint (on the wealth over the full trading interval). Optimal control problems with this combination of constraints are well known to be quite challenging even in the deterministic case, and of course become still more so when one deals with these same constraints in a stochastic setting. We nevertheless find that an ingenious variational approach of Rockafellar (Conjugate duality and optimization, CBMS-NSF series no. 16, SIAM, 1974), which played a key role in the precursor work noted above, is fully equal to the challenges posed by this problem, and leads naturally to an appropriate vector space of dual variables, together with a dual functional on the space of dual variables, such that the dual problem of maximizing the dual functional is guaranteed to have a solution (or Lagrange multiplier) when the problem constraints satisfy a simple and natural Slater condition. We then establish necessary and sufficient conditions for the optimality of a candidate wealth process in terms of the Lagrange multiplier, and use these conditions to construct an optimal portfolio.     

A differential evolution copula-based approach for a multi-period cryptocurrency portfolio optimization

Recent years have seen a growing interest among investors in the new technology of blockchain and cryptocurrencies and some early investors in this new type of digital assets have made significant gains. The heuristic algorithm, differential evolution, has been advocated as a powerful tool in portfolio optimization. We propose in this study two new approaches derived from the traditional differential evolution (DE) method: the GARCH-differential evolution (GARCH-DE) and the GARCH-differential evolution t-copula (GARCH-DE-t-copula). We then contrast these two models with DE (benchmark) in single and multi-period optimizations on a portfolio consisting of five cryptoassets under the coherent risk measure CVaR constraint. Our analysis shows that the GARCH-DE-t-copula outperforms the DE and GARCH-DE approaches in both single- and multi-period frameworks. For these notoriously volatile assets, the GARCH-DE-t-copula has shown risk-control ability, hereby confirming the ability of t-copula to capture the dependence structure in the fat tail.     

Enhancement of value investing strategies based on financial statement variables: the German evidence

This paper examines the added-value of combining traditional valuation ratios with each other as well as with some financial statement variables in the German stock markets during the 2000–2015 period. The results show that combination pays off and, moreover, that the benefits of combination are greater in Germany than in most other developed stock markets. Particularly, we find strong evidence of the added-value of using Piotroski’s F-score as a supplementary selection criterion for value stocks as well as for low-accrual stocks. Our results show further that the F-score also boosts the efficacy of other valuation ratios besides the book-to-price ratio. In addition, the inclusion of F-score besides a relative value measure tends to increase the average market equity of portfolio firms. The decomposition of the full-sample-period performance into separate bull- and bear-period performance shows clearly that the better performance of F-score-boosted portfolios is mostly attributable to their outperformance during bearish periods, even though on average, they also generate higher bull-period returns than the comparable value portfolios formed without F-score. The use of F-score as a supplementary criterion also increases the proportion of stocks that earn above-market-average returns during the subsequent holding period. For the first time in the financial literature, we also document a strong relationship between high F-score stocks and momentum stocks.     

Impact of website characteristics on relationship quality: a comparison of banks financial cooperatives

This study seeks to investigate differences exhibited by bank customers and members of financial cooperatives respecting website characteristics (website design, convenience, information quality, ease of use and security/confidentiality) and their impact on online relationship quality (composed of trust, commitment and satisfaction). An online survey was conducted with 476 banking sector customers (banks and financial cooperatives), followed by a confirmatory factors analysis and multigroup analysis using EQS 6.2 software. Results evidence a significant difference in terms of website design and security/confidentiality. The impact of these variables on relationship quality proves significantly higher in the case of banks. This study submits that web strategies used by banks and financial cooperatives to develop online relationship quality may vary based on the type of organization.     

<Emphasis Type="Italic">Shariah</Emphasis>-compliant equities: Empirical evaluation of performance in the European market during credit crunch

Islamic finance is based on the Islamic Jurisprudence as prescribed by the Shariah, and has witnessed significant growth and development in the recent decades. During the period of economic slowdown and following the financial crisis during FY 2007–2009, it was claimed that Islamic financial system seemed to be better in coping with economic slowdowns than conventional financial systems. The article analyses whether the same holds true for Shariah-compliant equities in the market, that is, whether Shariah-compliant equities perform better in the market as compared to the general market. Three portfolios are constructed based on the constituents of S&P Europe 350 to represent the overall market, the market without the financial firms and the market of Shariah-compliant equities. It is found that the portfolio of Shariah-compliant equities outperforms the other two portfolios in all aspects of analysis. However, it slightly underperforms the market portfolio when there is an upward growth trend in the economy. The findings of this article are very relevant for policymakers, investors and fund managers to determine policy matters, deciding on investment and marketing strategy for Islamic capital market products.     

Small-time ruin for a financial process modulated by a Harris recurrent Markov chain

We consider a nonstandard ruin problem where: (i) the increments of the process are heavy-tailed and Markov-dependent, modulated by a general Harris recurrent Markov chain; (ii) ruin occurs when a positive boundary is attained within a sufficiently small time. Our main result provides sharp asymptotics for the small-time probability of ruin, viz., P(sup? _{n≤δ u} S _n ≥u), where {S _n } denotes the discrete partial sums of the process and δ∈(0,1/μ), where μ is the mean drift. We apply our results to obtain risk estimates which quantify, e.g., repetitive operational risk losses or the extremal behavior for a GARCH(1,1) process.     

Prognose des Abwicklungsergebnisses mittels Chain-Ladder-Verfahren für abhängige Run-Off-Portfolios

In the present paper we analyse how the estimators from Merz u. Wüthrich (2007) could be generalised to the case of N correlated run-off triangles. The simultaneous view on N correlated subportfolios is motivated by the fact, that in practice a run-off portfolio often has to be divided in subportfolios, so that the homogeneity assumption of the claims reserving method on each subportfolio is satisfied. We derive an explicit formula for the process-variance, the estimation-error and the prediction error made by the forecast for the claims development result with the Chain-Ladder method. We illustrate the results by an example.     

Do Stars Shine? Comparing the Performance Persistence of Star Sell-Side Analysts Listed by Institutional Investor,the Wall Street Journal,and StarMine

We investigate the profitability persistence of the investment recommendations from analysts listed in four different star rankings, Institutional Investor magazine, StarMine’s “Top Earnings Estimators” and “Top Stock Pickers”, and The Wall Street Journal, and show the predictive power of each evaluation methodology. We found that only Buy and Strong Buy recommendations from the entire group of Star analysts outperform those of the Non-Stars in the year after election, while Sell and Strong Sell recommendations performed as those of the Non-Stars. We document that the highest average monthly abnormal return of holding a long-short portfolio, 0.97 %, is obtained by following the recommendations of the group of star sell-side analysts rated by StarMine’s “Top Earnings Estimators” during the period from 2003 to 2014. Since earnings are one of the main drivers of stock prices, the results obtained are in line with the notion that focusing on superior earnings forecasts is one of the top requirements for successful stock picks.     

Variables influencing the customer relationship management of banks

Banks are important role players to the economy of any country. However, to survive in a competitive business environment banks need to focus on building and maintaining client relationships and to identify how their employees influence these relationships. This study investigates the influence of variables, with regard to bank employees, on the customer relationship management (CRM) of banks. A literature study explains CRM, the banking industry and employees' involvement with banking clients. To assess the impact of the predetermined variables from literature on the CRM of banks, a number of hypotheses were constructed and tested empirically among a sample of banking clients. The findings reveal that the variables knowledgeability and attitude of bank employees have a statistically significant impact on the effectiveness of the CRM strategies of banks. Based on the findings of the empirical investigation, strategies are provided for banks to improve their employees' knowledgeability and attitude in order to ensure more effective CRM strategies.     

Mobile banking innovators and early adopters: How they differ from other online users?

The rapid pace of technological development has created opportunities for financial service providers to offer their services via multiple electronic channels. The mobile phone is one of the most promising but so far marginally adopted channel for using financial services by consumers. Earlier literature on innovation adoption argued that those among the first to adopt new innovations possess unique characteristics compared to the majority of consumers. This paper aims to study how mobile banking innovators and early adopters differ from other users of online banking services. An internet survey was conducted among customers of a large Scandinavian bank in Finland yielding 2,675 responses. Logistic regression was used to identify variables differentiating between users of mobile banking and other online banking services. Somewhat contradictory to earlier findings the results indicate that only age (p<0.0005) and gender (p=0.010) differentiate these two groups of customers, while education (p=0.957), income (p=0.624), occupation (p=0.596) and size of the household (p=0.151) were found to be insignificant in differentiating the groups. The results offer service providers better knowledge of the typical mobile banking user thus adding value to their marketing actions in the field of electronic banking.     

The role of electronic word of mouth,conventional media,and subjective norms on the intention to purchase <Emphasis Type="Italic">Sharia</Emphasis> insurance services

The aim of this study was to investigate the effect of electronic word of mouth (eWOM) and conventional media on subjective norms and intention to purchase Sharia insurance in Indonesian Muslim society. The research data consisted of 458 Muslim clients who were members of an online community and also policy holders of Sharia insurance in the three largest cities in Indonesia: Jakarta, Semarang, and Surabaya. This study used purposive sampling and structural equation modeling. The research showed that eWOM and conventional media can affect subjective norms. Additionally, subjective norms have a significant effect on the intention to purchase among Sharia insurance customers. This study validated the importance of the variables of eWOM and conventional media in influencing subjective norms and intention to purchase. For Sharia insurance company management, this study can serve as a very useful reference in drafting and formulating campaign strategies. This study also justifies the integrated relationship between eWOM and conventional media with subjective norms and intention to purchase Sharia insurance.     

Strong Increases in Downside Risk Aversion

A ranking of risk preferences is of economic interest insofar as it leads to unambiguous comparative statics predictions, and for this to be the case, the ranking must be a strict partial ordering. The ranking by greater risk aversion meets this demand at the second order, and yields a variety of well-known predictions concerning the effect of greater risk aversion on demands for insurance and risky assets, among many other applications. There has been less success at the third order, where ranking preferences by aversion to downside risk has not produced a strict partial ordering. The problem is that account has not been taken of the fact that an increase in downside risk aversion must induce changes in risk aversion as well. We propose a definition of stronger downside risk aversion that does yield a strict partial ordering by requiring a nested increase in both second- and third-order risk aversion, so that v is more strongly downside risk averse than u if v is more risk averse and more downside risk averse than u. We demonstrate that v being more strongly downside risk averse than u is characterized by v never liking any change in the probability distribution for y that induces a third-order stochastic dominance deterioration in the distribution for u(y). We apply the definition to obtain intuitive comparative statics predictions in the precautionary saving problem, and relate the definition to alternatives proposed in the literature.     

Analysing corporate insolvency in the Gulf Cooperation Council using logistic regression and multidimensional scaling

In this paper, we examine corporate insolvency in the Gulf Cooperation Council (GCC) region between 2004 and 2011. Data comprises 28 financial ratio variables from 112 firms. We use Logit regression with best-subset selection criteria to investigate the predictive value of the ratios in the GCC context, particularly cash flow-based ratios. We also examine the main dimensions of the ratios, and the weights firms attach to them, using 3-way Multidimensional Scaling (MDS). We find that a parsimonious Logit model with the profitability ratio EBITTL, the leverage ratio TLTA and the cash flow ratios CFFOTA and CFFOCL can predict insolvency, ex-ante, with 84.8, 95.6 and 73.9 % overall, type I and II accuracy, respectively. From MDS, we uncover four financial-ratio dimensions: (i) ‘Non-strategic sales activities’, (ii) ‘Profitability and financial stability balance’, (iii) ‘Sales activities against capital conversion’; and (iv) ‘Market value against cash generation’. Insolvent firms appear very specific and attach most salience to the ‘Non-strategic sales activities’ dimension, unlike solvent firms which attach more salience to the other three dimensions. Therefore, the results imply that, to reduce susceptibility to insolvency in the GCC, managers should focus less on non-strategic sales activities.     

Towards a better understanding of mobile banking: the impact of customer experience on trust and commitment

In the current context of ubiquitous connectedness through portable mobile devices and services, it is important to comprehend more fully the nature of consumer/bank interactions and relationships. At the same time, firms in the service sector are trying to provide customers with impactful positive experiences. This article examines the impact of mobile banking experience on trust and commitment based on the customer experience dimensions defined by Schmitt and expanded to include the negative aspect of the affective dimension. A total of 396 panellists of a recognized Canadian research firm responded to a self-administered online questionnaire. Findings demonstrate that the cognitive and negative affective dimensions of mobile experience impact trust, whereas the positive affective/sensory dimension influences commitment. The behavioural and social dimensions do not have significant impacts. This study enriches the theoretical corpus of knowledge in customer experience, relationship marketing and m-banking literature, lending practical implications for mobile services managers. Financial institutions, for example, should offer sensory mobile applications designed to appeal to the eye or to the touch (positive affective/sensory dimension), provide tools and information intended to arouse user curiosity and provoke reflection (cognitive dimension), while avoiding negative experiences which can lead to damaging feelings/emotions such as disappointment and anger (negative affective dimension).     

Tukey’s transformational ladder for portfolio management

Over the past half-century, the empirical finance community has produced vast literature on the advantages of the equally weighted Standard and Poor (S&P 500) portfolio as well as the often overlooked disadvantages of the market capitalization weighted S&P 500’s portfolio (see Bloomfield et al. in J Financ Econ 5:201–218, 1977; DeMiguel et al. in Rev Financ Stud 22(5):1915–1953, 2009; Jacobs et al. in J Financ Mark 19:62–85, 2014; Treynor in Financ Anal J 61(5):65–69, 2005). However, portfolio allocation based on Tukey’s transformational ladder has, rather surprisingly, remained absent from the literature. In this work, we consider the S&P 500 portfolio over the 1958–2015 time horizon weighted by Tukey’s transformational ladder (Tukey in Exploratory data analysis, Addison-Wesley, Boston, 1977): \(1/x^2,\,\, 1/x,\,\, 1/\sqrt{x},\,\, \text {log}(x),\,\, \sqrt{x},\,\, x,\,\, \text {and} \,\, x^2\), where x is defined as the market capitalization weighted S&P 500 portfolio. Accounting for dividends and transaction fees, we find that the 1/\(x^2\) weighting strategy produces cumulative returns that significantly dominate all other portfolio returns, achieving a compound annual growth rate of 18% over the 1958–2015 horizon. Our story is furthered by a startling phenomenon: both the cumulative and annual returns of the \(1/x^2\) weighting strategy are superior to those of the 1 / x weighting strategy, which are in turn superior to those of the \(1/\sqrt{x}\) weighted portfolio, and so forth, ending with the \(x^2\) transformation, whose cumulative returns are the lowest of the seven transformations of Tukey’s transformational ladder. The order of cumulative returns precisely follows that of Tukey’s transformational ladder. To the best of our knowledge, we are the first to discover this phenomenon.     

Not everybody wants to save the world

A consumer lens is used to examine investing behavior in this study. The study focuses on the importance given by investors to their economic and social investing goals (SIG). This approach redirects managerial attention from the investment to the investor and investing goals. The study finds that differences in environmental attitude, social investing efficacy, materialism, religiosity and protected values can explain disparities in investing goals. The findings suggest a segmentation approach based on differences in antecedent effects and economic and SIG.     

Risk bounds for factor models

Recent literature has investigated the risk aggregation of a portfolio \(X=(X_{i})_{1\leq i\leq n}\) under the sole assumption that the marginal distributions of the risks \(X_{i} \) are specified, but not their dependence structure. There exists a range of possible values for any risk measure of \(S=\sum_{i=1}^{n}X_{i}\), and the dependence uncertainty spread, as measured by the difference between the upper and the lower bound on these values, is typically very wide. Obtaining bounds that are more practically useful requires additional information on dependence.Here, we study a partially specified factor model in which each risk \(X_{i}\) has a known joint distribution with the common risk factor \(Z\), but we dispense with the conditional independence assumption that is typically made in fully specified factor models. We derive easy-to-compute bounds on risk measures such as Value-at-Risk (\(\mathrm{VaR}\)) and law-invariant convex risk measures (e.g. Tail Value-at-Risk (\(\mathrm{TVaR}\))) and demonstrate their asymptotic sharpness. We show that the dependence uncertainty spread is typically reduced substantially and that, contrary to the case in which only marginal information is used, it is not necessarily larger for \(\mathrm{VaR}\) than for \(\mathrm{TVaR}\).     

Optimal asset allocation for participating contracts under the VaR and PI constraint

ABSTRACT

Participating contracts provide a maturity guarantee for the policyholder. However, the terminal payoff to the policyholder should be related to financial risks of participating insurance contracts. We investigate an optimal investment problem under a joint value-at-risk and portfolio insurance constraint faced by the insurer who offers participating contracts. The insurer aims to maximize the expected utility of the terminal payoff to the insurer. We adopt a concavification technique and a Lagrange dual method to solve the problem and derive the representations of the optimal wealth process and trading strategies. We also carry out some numerical analysis to show how the joint value-at-risk and the portfolio insurance constraint impacts the optimal terminal wealth.     

Diversification benefits of risk portfolio models: a case of Taiwan’s stock market

How to construct effective investment strategies is a core issue for modern finance. In this paper, we investigate the benefits of various models by rebalancing portfolios using the daily stock return data in Taiwan. We further consider investment constraints in portfolios to ensure the feasibility of their applications. Using five performance criteria, we find the risk models, particularly the CVaR, yield higher ex ante and ex post performance than a naïve buy-and-hold portfolio. The two-stage regressions show that high return benefits are associated with a bear market while high reduction in risk is positively related to high volatility. Though VaR is regarded as a standard model applied in the real world, our findings suggest that CVaR can serve as a good alternative.     

Erklärung der privaten Krankenversicherungsnachfrage anhand ökonomischer und psychologischer Einflussfaktoren

To be able to plan measures insales planning successfully, informations are necessary about the expected trend of demand in the future. In this respecttheoretical funded andempirical relevant correlations between exogenous influencing factors and the process of demand must be systematically explored. Consequently for the private health insurance aglobal model was developed, which is the basis for presenting exemplarily an approach of explanation for the health cost insurance. Via this approach theshort-term fluctuations in the trend of demand, which were noticed in the past, can be traced satisfactorily. In this context besideseconomical alsopsychological influences like attitudes and expectations must be explicitly integrated in the approach of explanation. Naturally also the effects ofsociopolitical events, which are relevant to demand, were included in the analysis, especially as the process of demand for private health insurance is substantially marked by sociopolitical legislation.