Dynamics between patent latent variables and patent price

This paper focuses on studying the relationship between patent latent variables and patent price. From the existing literature, seven patent latent variables, namely age, generality, originality, foreign filings, technology field, forward citations, and backward citations were identified as having an influence on patent value. We used Ocean Tomo's patent auction price data in this study. We transformed the price and the predictor variables (excluding the dummy variables) to its logarithmic value. The OLS estimates revealed that forward citations and foreign filings were positively correlated to price. Both the variables jointly explained 14.79% of the variance in patent pricing. We did not find sufficient evidence to come up with any definite conclusions on the relationship between price and the variables such as age, technology field, generality, backward citations and originality. The Heckman two-stage sample selection model was used to test for selection bias. (C) 2011 Elsevier Ltd. All rights reserved.

Oxy anion-accelerated rearrangements

The alkali metal salts of 1,5-hexadien-3-ols undergo accelerated Cope rearrangements to the enolates of δ, ε-unsaturated carbonyl compounds. The generality of the rearrangement was investigated in numerous systems, particularly acyclic cases, and the effect of changes in substituents, counterions, solvents, and geometrical structures were noted and discussed. Applications of this methodology in synthesis included the synthesis of the insect pheromone frontalin, the preparation of selectively monoprotected 1,6-dicarbonyl compounds from 4-methoxy- and 4-phenylthio-1,5-hexadien-3-ols, and the construction of complex ring structures such as a D-homo-estratetraenone derivative.

Thermochemical estimates of the energetics of anionpromoted alkoxide fragmentations were made, and in all cases heterolytic cleavage was favored over hemolytic cleavage by 8.5-53 kcal/mol. The implication of these and other thermochemical estimates is that the anionic oxy-Cope rearrangement occurs via a concerted mechanism rather than a dissociation-recombination process. The concepts of anion-induced bond weakening were successfully applied to an accelerated [1,3]-shift of a dithiane fragment in a cyclohexenyl system. Trapping experiments demonstrated that > 85% of the [1,3]-shift occurred within a solvent cage. Attempts at promoting an intramolecular ene reaction using the potassium salts of 2,7-octadien-1-o1 and 2,8-nonadien-1-o1 were unsuccessful. A general review of anion-promoted bond reorganizations and anion substituent effects is also presented.

Um estudo da atenção primária à saúde mediante o indicador: Internações por condições sensíveis à atenção ambulatorial (CSAA)

A Atenção Primária à Saúde - APS é reconhecida como o nível fundamental e porta de entrada do sistema de atenção à saúde, sendo o lugar adequado onde pode ser atendida e resolvida a maior parte dos problemas de saúde. É considerada pela OMS como a principal proposta de modelo assistencial. Essa importância da APS leva a necessidade de pesquisas avaliativas dos seus resultados para adequação e melhoria de políticas e planos de ação delineados em relação à mesma. Pesquisas internacionais e nacionais são realizadas, nas quais indicadores relativos às atividades hospitalares estão sendo empregados com o objetivo de medir resultados como efetividade e acesso da APS. Um desses indicadores, desenvolvido por John Billings da Universidade de Nova York, na década de 90, consiste nas condições pelas quais as internações hospitalares por Condições Sensíveis à Atenção Ambulatorial (CSAA) deveriam ser evitadas caso os serviços da APS fossem efetivos e acessíveis. Utilizando-se o SIH-AIH/2008 e a lista brasileira de Internações por Condições Sensíveis a Atenção Primária, publicada em 2008, a proposta do presente trabalho é a de estudar os cuidados primários à saúde baseando-se nas ICSAA, na área urbana da cidade de Juiz de Fora-MG. Buscou-se responder sobre os efeitos que ocorrem nessas internações a partir das características individuais dos pacientes, das características das Unidades Básicas de Saúde-UBS (infraestrutura, produção e modelos assistenciais) e das condições sócio-econômicas/ambientais das áreas cobertas por UAPS e descobertas (sem UAPS), com a utilização de modelos multiníveis logísticos com intercepto aleatório. Buscou-se conhecer, também, a distribuição espacial das taxas padronizadas por idade das ICSAA nessas áreas e suas associações com as variáveis contextuais, utilizando-se ferramentas da análise espacial. Os resultados do presente trabalho mostraram que a porcentagem de internações por CSAA, foi de 4,1%. Os modelos assistenciais ESF e o Modelo Tradicional, base da organização da atenção primária no Brasil, não apresentaram no município, impacto significativo nas ICSAA, somente na forma de áreas descobertas tendo como referência as áreas cobertas. Também não foram significativas as variáveis de infraestrutura e produção das UAPS. Os efeitos individuais (idade e sexo) nas ICSAA foram significativos, apresentando probabilidades de significância menores que 1%, o mesmo acontecendo com o Índice de Desenvolvimento Social-IDS, que contempla as condições sociais, econômicas e ambientais das áreas analisadas. A distribuição espacial das taxas padronizadas por idade apresentou padrão aleatório e os testes dos Multiplicadores de Lagrange não foram significativos indicando o modelo de regressão clássico (MQO) como adequado para explicar as taxas em função das variáveis contextuais. Para a análise conjunta das áreas cobertas e descobertas foram fatores de risco: a variável econômica (% dos domicílios com renda até 2 SM), áreas descobertas tendo como referência as áreas cobertas e a região nordeste do município. Para as áreas cobertas as variáveis de produção das UAPS, econômica e a região nordeste apresentaram como fator de risco para as taxas de internação por CSAA.

Company financial performance: Does board size matter? Case of the EUROSTOXX50 index

[EN] This study analyzes the relationship between board size and economic-financial performance in a sample of European firms that constitute the EUROSTOXX50 Index. Based on previous literature, resource dependency and agency theories, and considering regulation developed by the OECD and European Union on the normative of corporate governance for each country in the sample, the authors propose the hypotheses of both positive linear and quadratic relationships between the researched parameters. Using ROA as a benchmark of financial performance and the number of members of the board as measurement of the board size, two OLS estimations are performed. To confirm the robustness of the results the empirical study is tested with two other similar financial ratios, ROE and Tobin s Q. Due to the absence of significant results, an additional factor, firm size, is employed in order to check if it affects firm performance. Delving further into the nature of this relationship, it is revealed that there exists a strong and negative relation between firm size and financial performance. Consequently, it can be asseverated that the generic recommendation one size fits all cannot be applied in this case; which conforms to the Recommendations of the European Union that dissuade using generic models for all countries.

Timeliness no Brasil: um estudo dos determinantes do prazo de divulgação das demonstrações contábeis das companhias não financeiras listadas na BM&FBOVESPA

Esta dissertação tem o propósito principal de fornecer evidências empíricas acerca dos fatores que influenciam as decisões dos gestores quanto ao prazo de divulgação das demonstrações contábeis anuais das companhias não financeiras listadas na BM&FBOVESPA. O prazo de divulgação, chamado defasagem, foi medido como o intervalo em dias entre o encerramento do exercício social e a data da primeira apresentação das Demonstrações Financeiras Padronizadas (DFPs). O foco da pesquisa foi a influência, sobre a defasagem, dos seguintes fatores não observáveis: monitoramento, complexidade contábil, governança corporativa, relatório de auditoria e performance. Com base na literatura revisada, foram formuladas proxies destinadas a captar os efeitos desses fatores. Para a consecução dos objetivos, foram estimados modelos econométricos por meio dos métodos: (i) Mínimos Quadrados Ordinários (MQO) com dados em corte transversal; (ii) MQO com dados agrupados (OLS pooled); e (iii) painel de dados. Os testes foram aplicados sobre um painel balanceado de dados, ou seja, 644 observações de 322 companhias, referentes aos exercícios 2010 e 2011. Os resultados das estimações revelaram que tendem a divulgar mais rapidamente suas demonstrações companhias: (i) com maior número de acionistas; (ii) com maior nível de endividamento; (iii) que aderiram a um entre os níveis diferenciados de governança corporativa da BM&FBOVESPA; (iv) que possuem maiores proporções de diretores independentes na composição da diretoria (board); e (v) que foram auditadas por uma entre as firmas de auditoria do grupo Big-4. Por outro lado, constatou-se que tendem a atrasar suas divulgações companhias que: (i) estão sujeitas à consolidação de balanços; (ii) tiveram suas demonstrações contábeis ressalvadas pelos auditores independentes; (iii) e que registraram resultados negativos (prejuízos). Adicionalmente, foram formuladas proxies para captar os efeitos das surpresas contidas nos resultados, uma delas tendo como base o benchmark para as expectativas do mercado, qual seja, a previsão dos analistas, no entanto, não foram constatados impactos das surpresas sobre o prazo de divulgação. Também não foram verificadas influências, sobre o timing, oriundas da proporção de investidores institucionais, da formação de blocos de controle, da regulação estatal, do nível de rentabilidade, do porte e tampouco da negociação de valores mobiliários em mercados estrangeiros. Os achados desta pesquisa podem contribuir não apenas para a literatura dedicada a essa linha de pesquisa, como também para investidores, analistas de mercado e reguladores. As nuances observadas para os exercícios analisados, que marcaram a adoção integral do padrão contábil alinhado às normas IFRS e a recuperação da economia brasileira em relação aos impactos da crise financeira mundial, permitiram relevantes constatações. Além disso, a relevância deste estudo é ampliada pelo ineditismo presente na aplicação de proxies ainda não utilizadas em ambiente nacional para explicar os prazos de divulgação.

Análisis econométrico de los casos de cáncer en mujeres

[ES] El presente Trabajo de Fin de Grado trata, en primera instancia, de proporcionar una visión detallada sobre los diferentes tipos de cáncer en mujeres, detallando los más padecidos entre ellas y facilitando una serie de datos relacionados con la incidencia, la mortalidad y la prevalencia a cinco años. Además de analizar los diversos factores que favorecen la aparición del cáncer en las personas. En la segunda parte del trabajo, se analiza a través de la especificación y estimación de modelos paramétricos, el efecto de diferentes variables sobre la supervivencia a esta enfermedad en las mujeres. Entre las variables que se han tenido en cuenta están la edad en el momento en que se diagnostica el cáncer, el tamaño del mismo y el grado, además de variables como la raza, si la mujer es de origen hispano y el estado civil. Los datos utilizados en el presente trabajo han sido obtenidos de la base de datos: SEER CANCER RESEARCH DATABASE, del Instituto Nacional de Cáncer de Estados Unidos (2013).

Fishery dynamics of the California market squid (Loligo opalescens), as measured by satellite remote sensing

Novel data on the spatial and temporal distribution of fishing effort and population abundance are presented for the market squid fishery (Loligo opalescens) in the Southern California Bight, 1992−2000. Fishing effort was measured by the detection of boat lights by the Defense Meteorological Satellite Program (DMSP) Operational Linescan System (OLS). Visual confirmation of fishing vessels by nocturnal aerial surveys indicated that lights detected by satellites are reliable indicators of fishing effort. Overall, fishing activity was concentrated off the following Channel Islands: Santa Rosa, Santa Cruz, Anacapa, and Santa Catalina. Fishing activity occurred at depths of 100 m or less. Landings, effort, and squid abundance (measured as landings per unit of effort, LPUE) markedly declined during the 1997−98 El Niño; landings and LPUE increased afterwards. Within a fishing season, the location of fishing activity shifted from the northern shores of Santa Rosa and Santa Cruz Islands in October, the typical starting date for squid fishing in the Bight, to the southern shores by March, the typical end of the squid season. Light detection by satellites offers a source of fine-scale spatial and temporal data on fishing effort for the market squid fishery off California, and these data can be integrated with environmental data and fishing logbook data in the development of a management plan.

内蒙古草原温度梯度上3个典型群落的能量平衡研究

通量测量点的能量收支总是表现出不平衡，即使在地势平坦、植被分布均一、稀疏植被下垫面的情况下也有约30%的能量失衡状况。能量平衡闭合 (EBC) 问题在验证涡度相关系统质量方面，得到了广泛的关注。实验在内蒙古草原3个地点，通过涡度相关系统附近移动能量平衡系统的测定手段，采用能量平衡余项法和最小二乘 (OLS) 线性回归法，研究了土壤热通量、净辐射及可供能量空间变异对能量平衡闭合的影响。 结果显示，EBC 在三个研究点的平均余项为8~19 W m-2，OLS 斜率为0.83~0.96。EBC 在土壤湿润情况的站点要高于干旱站点。 土壤热通量的空间变异三站点平均为白天48 W m-2 (占同时间 Rn 的13%)，夜间15 W m-2 (34%)，平均29 W m-2 (24%)。通过8个工作站的测量，这个变异会造成9% (从0.93到1.01) 的 OLS 斜率差别。夜间的能量平衡不闭合可以由土壤热通量的空间变异解释。如果在本研究的的三个草原站点上忽略了土壤热通量，则会造成较大的余项 (峰值时110 W m-2) 产生，从而使 OLS 斜率增大23%。特别是通量板埋置在地面以下30 mm处时，上层的土壤热储部分占到全部土壤热通量的50%，这不仅影响到 EBC 的大小，更起到调节土壤热通量与“真实的波形” 相一致的作用。如果该部分热储被忽略掉，EBC 余项会增加60 W m-2，OLS 斜率也会变化 (减少) 9%。用大尺度多点测量与涡度塔附近的小尺度测定相比较，后者表现出稍高的闭合率，即 OLS 斜率增加4%。 相对于土壤热通量，净辐射的空间变异较小，三站点平均为白天17 W m-2 (5%)，夜间7 W m-2 (13%)，平均 12 W m-2 (5%)。可以引起3% (从0.88到0.91) 的 OLS 斜率差异。研究结果还表明，风速校正应该在 Q7.1 净辐射仪中应用，校正后的结果与 CNR1 的结果在白天有吻合较好，但在其它时段仍有较大差异，特别是在夜间，风速校正基本不起作用，使得两种仪器间差异达20 W m-2。比较表明，风速校正可以提高白天 Rn 的6%，仅降低夜间0.3%。因此，无论是用余项法还是用 OLS 线性回归法，在比较使用不同仪器的站点间的闭合状况时 (本研究的结果适用于草地 Q7.1 与 CNR1 间的比较)，可以用9：00-15：00 h 时段的数据进行比较，这样可以避免因使用不同仪器的差异所造成的影响。用该时段的数据进行比较，仪器间的差异余项法小于6 W m-2，OLS 法小于3%。 受可供能量空间变异影响，三个站点平均 EBC 的不确定性为白天66 W m-2 (19%)，夜间23 W m-2 (50%)，平均42 W m-2 (36%);或者改变 OLS 斜率11%。用最大值和最小值来衡量，EBC 最大不确定性，正午时在站点 I、II 和 III 中分别为81，114和91 W m-2。故在探讨能量平衡和能量平衡闭合问题时，必须充分考虑到这种不确定性，否则会产生偏差，或者得出错误结论。 研究还表明，即使考虑到白天所有可供能量的最大不确定性，仍然不能使能量平衡闭合。中午 (12：00 h)，站点 I，II 和 III 仍然有14±15，48±12和47±14 W m-2 的失衡不能够归因于可供能量的空间不确定性。因此，其它影响因素也需进行细致的探讨。 在两站点不同测量深度土壤热通量结果的差异性比较实验中，无论在站点 I 还是 III，均表现出一致的结论，即随通量板布置深度加深，其测量结果会越高，与浅层布置的相比，差别可高达150 W m-2。深层土壤热通量的计算仍是个难题，需进一步研究。 在不同植被结构对净辐射测定影响的实验中发现，随刈割强度增加，一天中大部分时间净辐射均减少。正午依次为413，395和388 W m-2。无论正午还是全天合计，重度刈割地点的净辐射均比不刈割对照处理少6%，而且，在整个生长季也少6%，约合40,000 W m-2。测量高度不同，不同处理间对测定结果影响不同：刈割处理中，由于下垫面较均一，结果相差不显著;而对照则表现出较高的差异，用两配对样本T检验表明差异达到极显著 (P<0.000，9:30-15:00 h data)。当使用不同新旧程度的 domes 时，对净辐射结果会产生明显的影响。新 domes 的测量结果白天明显高，晚上明显低，使用了11个月的旧 domes，峰值时，白天低估25 W m-2，晚上高估10 W m-2。说明该差异在进行能量平衡闭合计算时，不能忽略。而全用新的和全用旧的进行比较，晚上仅有2-3 W m-2差异。 考虑生态系统中非生物因子对干扰条件下生物多样性动态和功能的影响，有助于更精确地阐明生物多样性-稳定性功能的关系。为此，设计了一个单因子刈割实验——内蒙古地区一种广泛存在的土地利用方式。主要目的是研究不同强度刈割影响下，微气候变量特别是能量平衡各分量和群落结构的变化及二者的关系。连续4年刈割，占第一位的优势种明显由低矮半灌木冷蒿 (Artemisia frigida) 取代了高大丛生禾草克氏针茅 (Stipa kylovii)。重度刈割下，针茅的盖度、生物量和丛重，群落叶面积、绿色生物量、凋落物量和群落高度一致低于轻度刈割/不刈割处理。微气候由于群落特征的这些变化也呈规律性变化。与对照相比，重度刈割降低了生长季土壤含水量的47.5%，但中午和日均土壤表面温度分别增加了7.4和1.2 °C，并且增加地表下2 cm土壤温度日较差 (日最高与最低温度之差) 4.2 °C。刈割处理由于凋落物少、反射强而表现出较低的净辐射，但土壤热通量显著提高，表现为土层加热和冷却快。因此，重度刈割处理较对照降低了可供能量8%，约合52,000 W m-2 。不同刈割强度间来看，NPP 或 LAI 与土壤热通量和净辐射的比值 (G/Rn) 以及波文比 (H/LE) 间呈负相关。重度刈割处理感热通量显著提高，但潜热通量在处理间差异不显著，表明未刈割处理虽然冠层伸展大，但是并没有导致更大的水分亏缺。未刈割处理增加了抵抗物种改变的能力，而刈割处理在连续一年一割的第四年显著增加了物种数，可能与因刈割影响而导致的群落结构与微气候的改变有关。本研究表明，未刈割处理可以减轻高温干旱季节的高温和干旱胁迫，表现出对环境变化的高抵抗性。未刈割处理的凋落物层和较高的垂直结构所形成的遮荫，可以形成一个阻挡蒸发的篱笆，这是维持其水分的保证。因此，为了恢复退化草原生态系统功能，需要修复能导致微气候变化的植物群落结构，否则难以成功。 本研究立足于原创性的实验研究，在中国特有的自然草原生态系统上开展，结合不同温度梯度的三地区涡度相关系统进行了能量平衡闭合的移动比较实验，以及结合常用土地利用方式的定点能量平衡实验。在翔实的数据基础上，为涡度相关方法的陆地表面能量平衡失衡问题提供了解释。增加了对两个主要能量流——土壤热通量和净辐射空间变异规律的认识，研究对于能量平衡和湍流通量相关研究是有价值的。在三个代表性地区首次利用多个净辐射仪和土壤热通量板的结果与三个标准的涡度相关系统进行了比较，这类量化失衡原因的相关研究应受到高度重视并进一步拓展，以提高对能量失衡的认识，进而推进水热和碳循环研究向更深层次发展。

表面处理对p-GaN欧姆接触的影响

分别用稀盐酸、王水以及(NH_4)_2S溶液处理p-GaN表面,通过测试样品表面Ols的X射线光电子能谱(XPS),比较了这些溶液去除p-GaN表面氧化层的能力;在经不同溶液处理后的样品表面,以相同的条件制作Ni/Au电极,并测试其与p-GaN的比接触电阻,结果表明经稀盐酸处理后的样品表面,由于其氧含量较高,不能与Ni/Au形成良好的欧姆接触,而经王水和(NH_4)_2S溶液处理后的p-GaN表面,能与Ni/Au形成良好的欧姆接触;最后,通过比较样品表面的Ga/N原子浓度比,探讨了王水处理p-GaN表面能够形成良好欧姆接触的原因.

中国通量观测网络(ChinaFLUX)能量平衡闭合状况的评价

涡度相关观测网络能够对生态系统的水碳通量及其气候背景资料进行长期观测,能量平衡闭合状况作为通量观测数据评价的一个重要参考指标,备受通量界研究者的重视.本研究运用OLS(OrdinaryLeastSquares)、RMA(ReducedMajorAxis)、EBR(EnergyBalanceRatio)和δ频率分布四种统计方法对湍流通量(显热和潜热)与有效能量(净辐射、土壤热通量、冠层热储量)的关系进行了分析,对ChinaFLUX各站点的能量平衡闭合状况进行了综合评价,给出了能量平衡闭合程度日变化和季节变化

硝酸铕与含氮冠醚配合物的电子结构和化学键

本文用XPS和INDO方法研究了硝酸铕与含氮冠醚配合物[Eu(NO_3)_2(2,2)]NO_3的电子结构。结合能和电荷分布数据指出,在配位原子中,电负性低的氮原子Nls结合能的化学位移比电负性高的氧原子Ols的大。在配合物中,氮原子转移至中心金属离子上的电荷比氧原子转移的多。铕与含氮冠醚配合物的化学键具有一定程度的共价性,电负性低的氮原子与铕的配位键(N→Eu)的共价性比电负性高的氧原子的配位键(O→Eu)的大。

稀土酞菁配合物的XPS研究

我们合成了稀土单酞菁配合物LnPcCl和LnPc(OAc)_2(Ln=Tb,Ho,Tm,Lu,Pc为酞菁根,OAc为乙酸根)。用XPS研究了它们的电子结构。结果指出,稀土酞菁配合物的化学键具有一定程度的共价性,其强度与电荷转移程度有关。L→Ln电荷转移不同于冠醚配合物,前者既有配位也含取代,后者纯系配位。且酞菁环系吸电子基团,电负性较高,故LnPc(OAc)_2中乙酸根的配位氧原子的Ols比Ln(OAc)_3的Ols结合能高。由于电荷转移程度与电负性、配位数等因素有关,LnPc(OAc)_2中Ln的配位数较高,LnPcCl中Cl的电负性较高,故LnPc(OAc)_2中Ln4d_(5/2)结合能低于LnPcCl。并讨论了配合物的分子组成及结构。

Alcohol income and health: a complicated but desirable mix

The aim of this thesis is to examine if a difference exists in income for different categories of drinkers in Ireland using the 2007 Slán data set. The possible impact of alcohol consumption on health status and health care utilisation is also examined. Potential endogeneity and selection bias is accounted for throughout. Endogeneity is where an independent variable included in the model is determined within the context of the model (Chenhall and Moers, 2007). An endogenous relationship between income and alcohol and between health and alcohol is accounted for by the use of separate income equations and separate health status equations for each category of drinker similar to what was done in previous studies into the effects of alcohol on earnings (Hamilton and Hamilton, 1997; Barrett, 2002). Sample selection bias arises when a sector selection is non-random due to individuals choosing a particular sector because of their personal characteristics (Heckman, 1979; Zhang, 2004). In relation to alcohol consumption, selection bias may arise as people may select into a particular drinker group due to the fact that they know that by doing so it will not have a negative effect on their income or health (Hamilton and Hamilton, 1997; Di Pietro and Pedace, 2008; Barrett, 2002). Selection bias of alcohol consumption is accounted for by using the Multinomial Logit OLS Two Step Estimate as proposed by Lee (1982), which is an extension of the Heckman Probit OLS Two Step Estimate. Alcohol status as an ordered variable is examined and possible methods of estimation accounting for this ordinality while also accounting for selection bias are looked at. Limited Information Methods and Full Information Methods of estimation of simultaneous equations are assessed and compared. Findings show that in Ireland moderate drinkers have a higher income compared with abstainers or heavy drinkers. Some studies such as Barrett (2002) argue that this is as a consequence of alcohol improving ones health, which in turn can influence ones productivity which may ultimately be reflected in earnings, due to the fact that previous studies have found that moderate levels of alcohol consumption are beneficial towards ones health status. This study goes on to examine the relationship between health status and alcohol consumption and whether the correlation between income and the consumption of alcohol is similar in terms of sign and magnitude to the correlation between health status and the consumption of alcohol. Results indicate that moderate drinkers have a higher income than non or heavy drinkers, with the weekly household income of moderate drinkers being €660.10, non drinkers being €546.75 and heavy drinkers being €449.99. Moderate Drinkers also report having a better health status than non drinkers and a slightly better health status than heavy drinkers. More non-drinkers report poor health than either moderate or heavy drinkers. As part of the analysis into the effect of alcohol consumption on income and on health status, the relationship between other socio economic variables such as gender, age, education among others, with income, health and alcohol status is examined.

Operational scales, sources of finance, and firms’ performance: evidence from Vietnamese longitudinal data

This study investigates a longitudinal dataset consisting of financial and operational data from 37 listed companies listed on Vietnamese stock market, covering the period 2004-13. By performing three main types of regression analysis - pooled OLS, fixed-effect and random-effect regressions - the investigation finds mixed results on the relationships between operational scales, sources of finance and firms' performance, depending on the choice of analytical model and use of independent/dependent variables. In most situation, fixed-effect models appear to be preferable, providing for reasonably consistent results. Toward the end, the paper offers some further explanation about the obtained insights, which reflect the nature of a business environment of a transition economy and an emerging market.

A Fast Nonlinear Model Identification Method

The identification of nonlinear dynamic systems using linear-in-the-parameters models is studied. A fast recursive algorithm (FRA) is proposed to select both the model structure and to estimate the model parameters. Unlike orthogonal least squares (OLS) method, FRA solves the least-squares problem recursively over the model order without requiring matrix decomposition. The computational complexity of both algorithms is analyzed, along with their numerical stability. The new method is shown to require much less computational effort and is also numerically more stable than OLS.