Reaching nirvana with a defaultable asset?

We study the optimal dynamic portfolio exposure to predictable default risk, taking inspiration from the search for yield by means of defaultable assets observed before the 2007–2008 crisis and in its aftermath. Under no arbitrage, default risk is compensated by an ‘yield pickup’ that can strongly attract aggressive investors via an investment-horizon effect in their optimal non-myopic portfolios. We show it by stating the optimal dynamic portfolio problem of Kim and Omberg (Rev Financ Stud 9:141–161, 1996) for a defaultable risky asset and by rigorously proving the existence of nirvana-type solutions. We achieve such a contribution to the portfolio optimization literature by means of a careful, closed-form-yielding adaptation to our defaultable asset setting of the general convex duality approach of Kramkov and Schachermayer (Ann Appl Probab 9(3):904–950, 1999; Ann Appl Probab 13(4):1504–1516, 2003).     

Persistent and transient productive inefficiency: a maximum simulated likelihood approach

The productive efficiency of a firm can be seen as composed of two parts, one persistent and one transient. The received empirical literature on the measurement of productive efficiency has paid relatively little attention to the difference between these two components. Ahn and Sickles (Econ Rev 19(4):461–492, 2000) suggested some approaches that pointed in this direction. The possibility was also raised in Greene (Health Econ 13(10):959–980, 2004. doi:10.1002/hec.938), who expressed some pessimism over the possibility of distinguishing the two empirically. Recently, Colombi (A skew normal stochastic frontier model for panel data, 2010) and Kumbhakar and Tsionas (J Appl Econ 29(1):110–132, 2012), in a milestone extension of the stochastic frontier methodology have proposed a tractable model based on panel data that promises to provide separate estimates of the two components of efficiency. The approach developed in the original presentation proved very cumbersome actually to implement in practice. Colombi (2010) notes that FIML estimation of the model is ‘complex and time consuming.’ In the sequence of papers, Colombi (2010), Colombi et al. (A stochastic frontier model with short-run and long-run inefficiency random effects, 2011, J Prod Anal, 2014), Kumbhakar et al. (J Prod Anal 41(2):321–337, 2012) and Kumbhakar and Tsionas (2012) have suggested other strategies, including a four step least squares method. The main point of this paper is that full maximum likelihood estimation of the model is neither complex nor time consuming. The extreme complexity of the log likelihood noted in Colombi (2010), Colombi et al. (2011, 2014) is reduced by using simulation and exploiting the Butler and Moffitt (Econometrica 50:761–764, 1982) formulation. In this paper, we develop a practical full information maximum simulated likelihood estimator for the model. The approach is very effective and strikingly simple to apply, and uses all of the sample distributional information to obtain the estimates. We also implement the panel data counterpart of the Jondrow et al. (J Econ 19(2–3):233–238, 1982) estimator for technical or cost inefficiency. The technique is applied in a study of the cost efficiency of Swiss railways.     

Asymmetric causality between military expenditures and economic growth in top six defense spenders

This study applies asymmetric causality tests, proposed by Hatemi-J (Asymmetric panel causality tests with an application to the impact of fiscal policy on economic performance in Scandinavia, 2011; Empir Econ 43(1):447–456, 2012), to revisit military expenditures-growth nexus for the world top six defense spenders during the period of 1988–2013. Empirical results indicate that the military expenditure-led hypothesis is supported in China and Japan. However, the growth-led hypothesis is supported in four countries, i.e. France, Russia, Saudi Arabia and US. Except for Saudi Arabia, strong economic growth by no means implies automatic expansion of military expenditures. Defense planning in these countries is a matter of matching their limited resources to attain the suitable priorities. The more threats they perceive, the more spend for defense. This evidence provides useful insight into the behavior of other potential defense suppliers.     

Kalai and Muller’s possibility theorem: a simplified integer programming version

We provide a respecification of an integer programming characterization of Arrovian social welfare functions introduced by Sethuraman et al. (Math Oper Res 28:309–326, 2003). By exploiting this respecification, we give a new and simpler proof of Theorem 2 in Kalai and Muller (J Econ Theory 16:457–469, 1977).     

A note on fourth-order risk aversion

Keenan et al. (J Risk Uncertain 24:264–277, 2002) introduced a measure of downside risk aversion (third-order risk aversion), and in Theorem 1, they showed four equivalent definitions of increased downside risk aversion. This result is thought as a higher-order extension of Theorem 3 in Diamond et al. (J Econ Theory 8:337–360, 1974). We consider fourth-order risk aversion and show four equivalent definitions of increased fourth-order risk aversion. Our result is thought as a higher-order extension of Theorem 1 in Keenan et al. (2002).     

Revisiting the issue of survivability and market efficiency with the Santa Fe Artificial Stock Market

The relevance of risk preference and forecasting accuracy for investor survival has recently been the focus of a series of theoretical and simulation studies. At one extreme, it has been proven that risk preference can be entirely irrelevant (Sandroni in Econometrica 68:1303–1341, 2000; Blume and Easley in Econometrica 74(4):929–966, 2006). However, the agent-based computational approach indicates that risk preference matters and can be more relevant for survivability than forecasting accuracy (Chen and Huang in Advances in natural computation, Springer, Berlin, 2005; J Econ Behav Organ 67(3):702–717, 2008; Huang in J Econ Interact Coord, 2015). Chen and Huang (Inf Sci 177(5):1222–1229, 2007, 2008) further explained that it is the saving behavior of traders that determines their survivability. However, institutional investors do not have to consider saving decisions that are the most influential investors in modern financial markets. Additionally, traders in the above series of theoretical and simulation studies have learned to forecast the stochastic process that determines which asset will pay dividends, not the market prices and dividends. To relate the research on survivability to issues with respect to the efficient markets hypothesis, it is better to endow agents with the ability to forecast market prices and dividends. With the Santa Fe Artificial Stock Market, where traders do not have to consider saving decisions and can learn to forecast both asset prices and dividends, we revisit the issue of survivability and market efficiency. We find that the main finding of Chen and Huang (2008) that risk preference is much more relevant for survivability than forecasting accuracy still holds for a wide range of market conditions but can fail when the baseline dividend becomes very small. Moreover, the advantage of traders who are less averse to risk is revealed in the market where saving decisions are not taken into account. Finally, Huang’s (2015) argument regarding the degree of market inefficiency is confirmed.     

An evaluation of the performance and suitability of R × C methods for ecological inference with known true values

Ecological inference refers to the study of individuals using aggregate data and it is used in an impressive number of studies; it is well known, however, that the study of individuals using group data suffers from an ecological fallacy problem (Robinson in Am Sociol Rev 15:351–357, 1950). This paper evaluates the accuracy of two recent methods, the Rosen et al. (Stat Neerl 55:134–156, 2001) and the Greiner and Quinn (J R Stat Soc Ser A (Statistics in Society) 172:67–81, 2009) and the long-standing Goodman’s (Am Sociol Rev 18:663–664, 1953; Am J Sociol 64:610–625, 1959) method designed to estimate all cells of R × C tables simultaneously by employing exclusively aggregate data. To conduct these tests we leverage on extensive electoral data for which the true quantities of interest are known. In particular, we focus on examining the extent to which the confidence intervals provided by the three methods contain the true values. The paper also provides important guidelines regarding the appropriate contexts for employing these models.     

A model of growth with inherited tastes

This research aims at studying a general equilibrium closed economy with overlapping generations and inherited tastes (aspirations), as in de la Croix (Econ Lett 53(1):89–96, 1996). It shows that the interaction between the intensity of aspirations and the elasticity of substitution of effective consumption affects the qualitative and quantitative long-term dynamics from both local and global perspectives. The related literature is extended by showing that (1) the Neimark–Sacker bifurcation found by de la Croix (1996) does not necessarily give rise to fluctuations and (2) endogenous (long-lasting) fluctuations occur through the emergence of period-doubling bifurcations.     

Keyword auctions with budget-constrained bidders

We study a keyword auction model where bidders have constrained budgets. In the absence of budget constraints, Edelman et al. (Am Econ Rev 97(1):242–259, 2007) and Varian (Int J Ind Organ 25(6):1163–1178, 2007) analyze “locally envy-free equilibrium” or “symmetric Nash equilibrium” bidding strategies in generalized second-price auctions. However, bidders often have to set their daily budgets when they participate in an auction; once a bidder’s payment reaches his budget, he drops out of the auction. This raises an important strategic issue that has been overlooked in the previous literature: Bidders may change their bids to inflict higher prices on their competitors because under generalized second-price, the per-click price paid by a bidder is the next highest bid. We provide budget thresholds under which equilibria analyzed in Edelman et al. (Am Econ Rev 97(1):242–259, 2007) and Varian (Int J Ind Organ 25(6):1163–1178, 2007) are sustained as “equilibria with budget constraints” in our setting. We then consider a simple environment with one position and two bidders and show that a search engine’s revenue with budget constraints may be larger than its revenue without budget constraints.     

A short proof of Deb’s Theorem on Schwartz’s rule

Schwartz in (Nous,7, 1972, Definition, 3) introduces a generalization of the Condorcet criterion, which is the classical approach to rational choice in the context of cycles, and he defines the Schwartz set. Deb (J Econ Theory 16:103–110, 1977) shows that the Schwartz set consists of the maximal elements according to the transitive closure of the asymmetric part of a binary relation corresponding to a choice process or representing the decision maker’s preferences. This note provides a short and simple proof of Deb’s theorem on the characterization of the Schwartz set.     

New axioms for immediate acceptance

Following Kojima and Ünver (Econ Theory 55(3):515–544, 2014) and Afacan (Math Soc Sci 66(2):176–179, 2013), this paper provides two characterizations of the Boston school choice mechanism determined by the student-proposing immediate acceptance algorithm. A mechanism is the Boston mechanism if and only if it satisfies one of the following two groups of axioms: favoring higher ranks and weak fairness; favoring higher ranks, rank monotonicity, and rank rationality.     

Universally optimal designs under mixed interference models with and without block effects

The literature on neighbor designs as introduced by Rees (Biometrics 23:779–791, 1967) is mainly devoted to construction methods, providing few results on their statistical properties, such as efficiency and optimality. A review of the available literature, with special emphasis on the optimality of neighbor designs under various fixed effects interference models, is given in Filipiak and Markiewicz (Commun Stat Theory Methods 46:1127–1143, 2017). The aim of this paper is to verify whether the designs presented by Filipiak and Markiewicz (2017) as universally optimal under fixed interference models are still universally optimal under models with random interference effects. Moreover, it is shown that for a specified covariance matrix of random interference effects, a universally optimal design under mixed interference models with block effects is universally optimal over a wider class of designs. In this paper the method presented by Filipiak and Markiewicz (Metrika 65:369–386, 2007) is extended and then applied to mixed interference models without or with block effects.     

Interest rate dynamics and volatility transmission in the European short term interest rate market

This paper investigates the price and volatility relationship in European short-term interest rate markets. Cointegration analysis is used to analyse the long and short run relationship and a GARCH BEKK model is estimated to analyse the volatility transmission between the markets. The stability of the long run relationship is also examined using Bai and Perron (Econometrica 66(1),47–78, 1998, J Appl Econ 18(1):1–22, 2003) structural break methodology. The results show that the relationship between the EURIBOR spot deposit rate and the EURIBOR future contract has changed significantly since 2001 and several structural breaks are present in the 13 year sample period. During periods where there is a long run relationship present the spot deposit rate generally leads the future rate in price discovery. In the short run there is bi-directional causality present between the markets. There is also significant evidence of volatility transmission from the spot market to the futures market throughout the sample period.     

Adjusted Pearson Chi-Square feature screening for multi-classification with ultrahigh dimensional data

Huang et al. (J Bus Econ Stat 32:237–244, 2014) first proposed a Pearson Chi-Square based feature screening procedure tailored to multi-classification problem with ultrahigh dimensional categorical covariates, which is a common problem in practice but has seldom been discussed in the literature. However, their work establishes the sure screening property only in a limited setting. Moreover, the p value based adjustments when the number of categories involved by each covariate is different do not work well in several practical situations. In this paper, we propose an adjusted Pearson Chi-Square feature screening procedure and a modified method for tuning parameter selection. Theoretically, we establish the sure screening property of the proposed method in general settings. Empirically, the proposed method is more successful than Pearson Chi-Square feature screening in handling non-equal numbers of covariate categories in finite samples. Results of three simulation studies and one real data analysis are presented. Our work together with Huang et al. (J Bus Econ Stat 32:237–244, 2014) establishes a solid theoretical foundation and empirical evidence for the family of Pearson Chi-Square based feature screening methods.     

Technological change and timing reductions in greenhouse gas emissions

In 2007 Nicholas Stern’s Review (in Science 317:201–202, 2007) estimated that global GDP would shrink by 5–20% due to climate change which brought forth calls to reduce emissions by 30–70% in the next 20 years. Stern’s results were contested by Weitzman (in J Econ Lit XLV(3):703–724, 2007) who argued for more modest reductions in the near term, and Nordhaus (in Science 317:201–202, 2007) who questioned the low discount rate and coefficient of relative risk aversion employed in the Stern Review, which caused him to argue that ‘the central question about global-warming policy—how much how, how fast, and how costly—remain open.’ We present a simulation model developed by Färe et al. (in Time substitution with application to data envelopment analysis, 2009) on intertemporal resource allocation that allows us to shine some light on these questions. The empirical specification here constrains the amount of undesirable output a country can produce over a given period by choosing the magnitude and timing of those reductions. We examine the production technology of 28 OECD countries over 1992–2006, in which countries produce real GDP and CO₂ using capital and labor and simulate the magnitude and timing necessary to be in compliance with the Kyoto Protocol. This tells us ‘how fast’ and ‘how much’. Comparison of observed GDP and simulated GDP with the emissions constraints tells us ‘how costly’. We find these costs to be relatively low if countries are allowed reallocate production decision across time, and that emissions should be cut gradually at the beginning of the period, with larger cuts starting in 2000.     

Replicating the R&D investments and financial structure relationship: evidence from Borsa İstanbul

I revisit the empirical relationship between R&D investments and financial structure by trying to replicate seminal paper of Aghion et al. (J Eur Econ Assoc 2:277–288, 2004). In the widely cited study, Aghion et al. (2004) found evidence of a nonlinear (an inverted U-shape) relationship—firms with positive R&D tend to use more debt than firms with zero R&D, but the use of debt falls with R&D intensity—in a sample of U.K. firms from 1990 to 2002. In order to review their significant findings, I use panel data of 177 Turkish manufacturing firms listed in Borsa ?stanbul from 2007 to 2016. Using Aghion et al.’s (2004) model specifications, I found no evidence of an inverted U-shape relationship or of any effect of R&D intensity on the leverage ratio. The study thus suggests that the effect of R&D investments on the financial structure may vary with the different samples of countries and cannot be universally generalized.     

Governance of tax courts

This paper attempts to penetrate the “black box” of the judiciary through an empirical investigation of the Italian tax courts of first instance. Both judicial delay and two-stage Data Envelopment Analysis approach with bootstrap are used to measure the efficiency of the court system and to further identify the main determinants of efficiency which, in line with the previous literature, seem to be mostly related to the judges’ effort. The study also takes advantage of an idiosyncratic feature of this branch of the Italian judiciary—in which judges are temporarily appointed and can continue to practice an external (though not conflicting) profession—to assess the impact of opportunity costs on the behavior of judges. The overall outcome confirms that judges maximize utility “the same as everybody else does” (Posner, Supreme Court Econ Rev 3:1–41, 1993).     

Poverty trap,boom and bust periods and growth. A nonlinear model for non-developed and developing countries

This work investigates the qualitative and quantitative dynamics of a Solow–Swan growth model with differential savings as proposed by Böhm and Kaas (J Econ Dyn Control 24:965–980, 2000) assuming the shifted Cobb–Douglas (SCD) production function (see Capasso et al. in Nonlinear Anal. 11:3858–3876, 2010) which makes it possible to consider the long-run dynamics of non-developed and developing countries as well as that of developed economies. The resulting model is described by a nonlinear discontinuous map generating both a poverty trap and complex dynamics. Furthermore, multistability phenomena may emerge: besides the “vicious circle of poverty”, long-run behaviours may include boom and bust periods. Complex basins can emerge, hence, economic policies trying to raise the capital per capita may fail and economies may be captured by the poverty trap.     

Can structural change explain the Meese-Rogoff puzzle?

This paper provides empirical evidence suggesting that fundamentals matter for stock price fluctuations once temporal instability underpinning stock price-relations is accounted for. Specifically, this study extends the out-of sample forecasting methodology of Meese and Rogoff (J Int Econ 14:3–24 (1983)) to the stock market after explicitly testing for parameter nonconstancy using recursive techniques. The predictive ability of a present value model based on Imperfect Knowledge Economics (IKE) is found to match that of the pure random walk benchmark at short forecasting horizons and to perform significantly better at medium to longer-run horizons based on conventional measures of predictability and direction of change statistics. In addition, the presence of a cointegrating relation is found only within regimes of statistical parameter constancy. Augmenting the MR methodology in a piecewise linear fashion yields empirical results in favor of a fundamentals-based account of stock price behavior overturning the recent results of Flood and Rose (2010).     

A continuous-time heterogeneous duopoly model with delays

In this paper, the continuous-time version with delays of the model of Tramontana (Econ Model 27(1):350–357, 2010) is presented. The stability of the equilibrium point is discussed by analyzing the distribution of roots of associated characteristic equation. It is found that combining marginal costs with time delays gives rise to different economic scenarios, where stability switches may appear and Hopf bifurcations occur within certain range of parameters.