THE PROBLEM OF ESTIMATING CAUSAL RELATIONS BY REGRESSING ACCOUNTING (SEMI) IDENTITIES

Inferences about the coefficient values of a model estimated with a linear regression cannot be made when both the dependent and the independent variable are part of an accounting (semi) identity. The coefficients will no longer indicate a causal relation as they must adapt to satisfy the identity. A good example is an investment-cash flow sensitivity model. Este trabajo habla de la imposibilidad de extraer conclusiones sobre el valor de los coeficientes de un modelo de regresión lineal que intenta estimar una relación causal, cuando tanto la variable dependiente como la variable independiente forman parte de una (semi) identidad contable. Los coeficientes no sirven para explicar la relación causal, ya que su valor se adaptará para cumplir la identidad. Como ejemplo ilustrativo se presenta el modelo de la sensibilidad de la inversión al cash-flow.Sensibilidad de la inversión al cash flow, identidades contables, semi-identidades contables Investment-cash flow sensitivities, Accounting identities, Accounting semi-identities

DETERMINANTES DEL CONSERVADURISMO FINANCIERO DE LAS EMPRESAS ESPAÑOLAS

The objective of this work is to analyse the factors motivating firms to follow a conservative (or low-leverage) financial policy over several years. We carry out a study on a sample of 1,396 Spanish firms in the period 1993-2001. Using logit regression and various difference of means analyses, we test the influence of a number of variables associated with the pecking order theory, optimal capital structure theory and information asymmetries. Our findings show that conservative firms have a capital structure determined by the cash flows generated and their investment in tangible and intangible fixed assets, in accordance therefore with the pecking order theory. The findings do not provide support either for the optimal capital structure theory or for the role of information asymmetries, since in the majority of cases the results are not significant and/or contrary to what is predicted. El objetivo de este trabajo es analizar los factores por los cuales una empresa sigue una política financiera conservadora o de bajo endeudamiento durante varios años. Se lleva a cabo el estudio con una muestra de 1.396 empresas para el periodo 1993-2001 y mediante regresión logit y diferentes análisis de diferencias de medias se testa la influencia de varias variables relativas a la teoría de la jerarquía, de la estructura financiera y a asimetrías informativas. Los resultados muestran que las empresas conservadoras tienen una estructura financiera determinada por los cash-flows generados y por las inversiones en inmovilizado material e inmaterial, acorde, por tanto, con la teoría de la jerarquía financiera. Los resultados para la teoría de la estructura financiera óptima y para las asimetrías informativas son poco significativos y, en algunos casos, contrarios a lo que predicen.Conservadurismo financiero, Estructura de capital Financial conservatism, capital structure.

The role of government policies for Italian firms during the COVID-19 crisis

This paper aims to respond to this research question: “How effective have government incentives been in preserving firm profitability and growth during the COVID-19 crisis?”. We used a large, representative sample of Italian companies, which has produced a deeper study than the macro analyses provided by national statistics. Results shows that government policies alleviated the negative effects of the pandemic on troubled companies, but it was not enough to maintain the same financial health as firms that did not need this support. Small companies were the most adversely affected by the pandemic.We are grateful to two anonymous reviewers and Laura Ballester (Editor-in-Chief) for helpful comments and suggestions. We also benefited from comments offered by Proff. Antonia Madrid, Juan Francisco Martín Ugedo, Francesco Cappa, Alfio Cariola and Tiziana La Rocca. All errors are our own responsability. Open Access Funding provided by Universidad Politécnica de Cartagena

Modeling long term Enhanced in situ Biodenitrification and induced heterogeneity in column experiments under different feeding strategies

Enhanced In situ Biodenitrification (EIB) is a capable technology for nitrate removal in subsurface water resources. Optimizing the performance of EIB implies devising an appropriate feeding strategy involving two design parameters: carbon injection frequency and C:N ratio of the organic substrate nitrate mixture. Here we model data on the spatial and temporal evolution of nitrate (up to 1.2 mM), organic carbon (ethanol), and biomass measured during a 342 day-long laboratory column experiment (published in Vidal-Gavilan et al., 2014). Effective porosity was 3% lower and dispersivity had a sevenfold increase at the end of the experiment as compared to those at the beginning. These changes in transport parameters were attributed to the development of a biofilm. A reactive transport model explored the EIB performance in response to daily and weekly feeding strategies. The latter resulted in significant temporal variation in nitrate and ethanol concentrations at the outlet of the column. On the contrary, a daily feeding strategy resulted in quite stable and low concentrations at the outlet and complete denitrification. At intermediate times (six months of experiment), it was possible to reduce the carbon load and consequently the C:N ratio (from 2.5 to 1), partly because biomass decay acted as endogenous carbon to respiration, keeping the denitrification rates, and partly due to the induced dispersivity caused by the well developed biofilm, resulting in enhancement of mixing between the ethanol and nitrate and the corresponding improvement of denitrification rates. The inclusion of a dual-domain model improved the fit at the last days of the experiment as well as in the tracer test performed at day 342, demonstrating a potential transition to anomalous transport that may be caused by the development of biofilm. This modeling work is a step forward to devising optimal injection conditions and substrate rates to enhance EIB performance by minimizing the overall supply of electron donor, and thus the cost of the remediation strategy.Peer ReviewedPostprint (author's final draft

Edad y tamaño empresarial y ciclo de vida financiero

The aim of this paper is to analyze whether some of the empirical implications of the Berger and Udell's (1998) financial growth cycle hold. We use a sample of 22.842 observations for year 2003 and test several hypothesis through MANOVA analysis. Results show that companies tend to have different financing structures depending on age and size. The hypothesis about equity is not confirmed, because the older the company is the higher tends to be its value, caused by the increasing reserves. On the other hand, the risk of the company decreases with age. Results related to trade credit, short term credit and financing deficit are mixed, not significant or contrary to the considered hypothesis. El objetivo de este trabajo es examinar si se cumplen algunas de las implicaciones empíricas del ciclo de vida financiero planteado por Berger y Udell (1998). Para ello se utiliza una muestra de 22.842 observaciones para el año 2003 y mediante tests MANOVAs se contrastan diversas hipótesis. Los resultados obtenidos muestran que las empresas tienen distintas estructuras financieras dependiendo de la edad y el tamaño. La tendencia general es que a mayor edad, mayor presencia de fondos propios, ocasionada por el fuerte incremento de los beneficios retenidos, siendo este resultado contrario a la hipótesis planteada. Por otro lado, el riesgo asumido por las empresas disminuye con la edad. La evidencia relativa al empleo de crédito comercial, deuda financiera a corto plazo y déficit financiero es mixta, no significativa, o contraria a las hipótesis planteadas, especialmente para el caso del factor edad.Edad, tamaño, ciclo de vida financiero, asimetría informativa, financiación empresarial. Age, size, financial growth cycle, information asymmetries, corporate finance.

What determines the decision to apply for credit? Evidence for Eurozone SMEs

This study examines the decision by firm owners to apply, or not, for intermediated debt. Based on a sample of SMEs in 9 European countries over the period 2009-2012, we examine firm characteristics, institutional and cultural factors, along with time, industry and year variables. We focus our analyses in two distinct groups of firms, those that applied for debt and firms that did not apply for fear of rejection. We find evidence that firm age, size and existing debt capacity matter, as do bank and liquidity conditions. We provide evidence for the first time that national culture correlates to the decisions to apply or not for credit. Policy implications of these findings are discussed

Are the implications of the financial growth cycle confirmed for Spanish SMEs?

The aim of this paper is to analyze whether some of the empirical implications of the financial growth cycle hold in a sample of Spanish SMEs. We use a sample of 5,944 observations for the year 2007 and test several hypotheses using MANOVA analysis. The results show that companies tend to have different financing structures depending on their age and size. Hypotheses about trade credit, short term debt and risk are confirmed with respect to age, as the younger companies tend to use proportionally more trade credit and short term debt, and are riskier. Size is also associated in the expected way with trade credit, relative trade credit and relative short-term financial debt. On the other hand hypotheses about equity and the financing deficit are not confirmed. The effect of a pecking order behaviour over a long period of time may provide an explanation of why these two hypotheses are not confirmed

Two-sample PLL with improved frequency response applied to single-phase current sensorless bridgeless PFCs

A new implementation of the recently proposed fixed-frequency two-sample (2S) quadrature generation subsystem (QSG) digital Phase Locked Loop PLL, applicable to single-phase Power Factor Correction (PFC), is proposed. Its characteristics are high accuracy and low computational burden. The proposed PLL includes a frequency feedback loop to improve the synchronization under line frequency variations. Its performance within a digital controller of a current sensorless bridgeless PFC is evaluated by simulations and experimentally. The obtained results are compared with previously published PLLs in the literature.This work has been supported by the Spanish Ministry of Economy and Competitiveness under grant TEC2014-52316-R ECOTREND Estimation and Optimal Control for Energy Conversion with Digital Devices

Health Literacy: a crucial determinant of vaccination decision-making

We read with interest the Review by Buchy et al. (2020) summarizing the evidence on the micro (patients, healthcare workers), meso (vaccine manufacturers), and macro (wider society) determinant sof influenza vaccination in pregnant women worldwide. We agree with the authors that improvements in vaccination coverage could be gained with better training for health care workers about communicating the benefits of vaccination and the risks associated with influenza infection, as well as education about such benefits to pregnant women

Performance analysis of 1ϕ T/4 PLLs with secondary control path in current sensorless bridgeless PFCs

New power factor correction (PFC) stages such as bridgeless converters and the associated current shaping techniques require grid synchronization to ensure unity Displacement Power Factor (DPF). Sensorless line current rebuilding algorithms also need synchronization with the line voltage to compensate at least for part of the current estimation error. The application of a secondary control path to reach faster and more robustly the proper operation point previously applied in single/three-phase PLLs in grid connected converters is here proposed for the current sensorless bridgeless PFCs. This work analyzes the performance of three single-phase T/4 PLL structures, first without secondary control path, and later with feedforward and feedback secondary control paths, both in simulation and experimentally, and evaluates their applicability to current sensorless digitally controlled single phase bridgeless PFCs based on the current rebuilding technique.This work has been supported by the Spanish Ministry of Economy and Competitiveness under grant TEC2014-52316-R ECOTREND Estimation and Optimal Control for Energy Conversion with Digital Devices