PREDICTABILITY AND COMPLEXITY IN MACROECONOMICS. THE CASE OF GROSS FIXED CAPITAL FORMATION IN THE ROMANIAN ECONOMY

There is a relationship between predictability and complexity. The problem of evaluating the complexity of the macroeconomic phenomenon can be reduced to decomposition into its principal components (which may have, in their turn, a certain degree of complexity) and to identify its common sources of evolution that are predictable. In this paper, we evaluate the predictability of economic indicators and continue with its decomposition until the simplest sources allowed by available statistical data are obtained, then use this predictable sources to construct a forecasting model.predictability, complexity, principal components, consumption, investment, foreign trade, time series forecasting

The Relation between Predictability and Complexity: Domestic and Public Consumption in the Romanian Economy

We continue with the problem of the relation between predictability and complexity in the Romanian economy, analyzing other two components of GDP: domestic consumption and public consumption. The basic idea of this work is that the unpredictability of a system gives a measure of its complexity, so that in order to predict a future state of a complex system one must find the system structure explained by some simpler components that can be predicted. The complexity of the economic system is reflected in the synthetic macroeconomic indicators (GDP and its components). We find the principal components of the macroeconomic variables as a preprocessing step and model them as linear combinations of some simpler non observable predictable variables; we have constructed empirical models for domestic and public consumption; it was shown that these models are sufficiently accurate to predict for two or three periods ahead.complexity, predictability, consumption, complexity pursuit, time series forecasting

Prospects for the Evolution of the Economic Sectors’ Behavior

This paper is a synthesis of the research results obtained over the interval 2008- 20094. The problem we addressed was the following: how the evolution of an economic sector’s output was influenced when an exogenous shock occurred within its basic factors, namely the received intermediate consumptions, wage remuneration, taxes on products, gross fixed capital formation, foreign trade (expressed through the ratio of the sector’s imports to exports). The most significant distortions that may determine in circumstances of crisis severe disturbances in the functioning of the economic system were signaled.economic sectors, exogenous shock, macroeconomic simulations

Analysis of Foreign Imbalances and Exchange Rate Policy in the Romanian Economy

Considering the previous year's results, the paper re-addresses the issue of inflationary shocks dynamics and the dynamics of the foreign imbalance - induced shocks. The ideea of a correlation between the foreign imbalances and the output gap was first introduced by Acad. Emilian Dobrescu (2004) and provides an answer to certain behaviors specific to the Romanian transition economy. The paper presents an econometric analysis of the foreign imbalances and exchange rate policies, on the basis of certain short-term error-correcting econometric models (mothly data series) that reveal the correlations between the output gap and the foreign and exchange rate imbalances, the adjustment speed to the long-term balance, as well as the reaction towards the stability condition. At this stage, the previous year's results are used .foreign imbalances, output gap, exchange rate policy;

Traffic medicine–related research : a scientometric analysis

OBJECTIVE: Traffic crashes and related injuries are important causes of morbidity and mortality and impose insofar an important burden on public health. However, research in this area is often under-funded. The aim of this study was to analyse quantity, evolution and geographic distribution of traffic medicine-related research. This multi-sectorial field covers both transport and health care sectors. DESIGN: A scientometric approach in combination with visualizing density equalizing mapping was used to analyse published data related to the field of traffic medicine between 1900 and 2008 within the "Web of Science" (WoS) database. RESULTS: In total, 5,193 traffic medicine-associated items were produced between 1900 and 2008. The United States was found to have the highest research activity with a production of n = 2,330 published items, followed by Germany (n = 298) and Canada (n = 219). Cooperation analyses resulted in a peak of published multilateral cooperations in the year of 2003. The country with the highest multilateral activity was the USA. The average number of cited references per publication varied heavily over the last 20 years with a maximum of 27.67 in 1995 and a minimum of 15.08 in 1998. Also, a further in-depth analysis was performed with a focus solely on public health aspects which revealed similar trends. CONCLUSIONS: Summarizing the present data it can be stated traffic medicine-related research productivity grows annually. Also, an active networking between countries is present. The data of the present study may be used by scientific organisations in order to gain detailed information about research activities in this field which is extremely important for public health

Scoliosis : density-equalizing mapping and scientometric analysis

Background: Publications related to scoliosis have increased enormously. A differentiation between publications of major and minor importance has become difficult even for experts. Scientometric data on developments and tendencies in scoliosis research has not been available to date. The aim of the current study was to evaluate the scientific efforts of scoliosis research both quantitatively and qualitatively. Methods: Large-scale data analysis, density-equalizing algorithms and scientometric methods were used to evaluate both the quantity and quality of research achievements of scientists studying scoliosis. Density-equalizing algorithms were applied to data retrieved from ISI-Web. Results: From 1904 to 2007, 8,186 items pertaining to scoliosis were published and included in the database. The studies were published in 76 countries: the USA, the U.K. and Canada being the most productive centers. The Washington University (St. Louis, Missouri) was identified as the most prolific institution during that period, and orthopedics represented by far the most productive medical discipline. "BRADFORD, DS" is the most productive author (146 items), and "DANSEREAU, J" is the author with the highest scientific impact (h-index of 27). Conclusion: Our results suggest that currently established measures of research output (i.e. impact factor, h-index) should be evaluated critically because phenomena, such as self-citation and co-authorship, distort the results and limit the value of the conclusions that may be drawn from these measures. Qualitative statements are just tractable by the comparison of the parameters with respect to multiple linkages. In order to obtain more objective evaluation tools, new measurements need to be developed

Effects of (complementary) polyelectrolytes characteristics on composite calcium carbonate microparticles properties

This study follows the possibility to tune the thermal stability of some CaCO3/polymer composites by crystal growth from supersaturated solutions controlled by polymer structure or by using nonstoichiometric polyelectrolyte complexes (NPECs). As the ratio between the organic and inorganic parts in the composites controls the Ca2+/polymer network crosslinking density, the CaCO3/polymer weight ratio was kept constant at 50/1, varying the initial concentration of the polyanions solutions (0.05 or 0.06 wt.%), the NPECs molar ratio , n+/n- (0.2 or 0.4), or the inorganic precursors concentration (0.25 or 0.3 M). Poly(2-acrylamido-2-methylpropanesulfonic acid-co-acrylic acid) (PSA) and chondroitin-4-sulfate (CSA) were used as polyanions. Some NPEC dispersions, prepared with the same polyanions and poly(allylamine hydrochloride) (PAH), were also used for calcium carbonate crystallization. The characteristics of the prepared composites were investigated by scanning electron microscopy (SEM), flow particle image analysis (FPIA), particles charge density (CD), zeta-potential (ZP). The thermal stability of the composite particles was investigated as compared to bare CaCO3 microparticles prepared at the same initial inorganic concentrations

Bibliometrics Analysis and Density-Equalizing Mapping

The objective of this paper is to provide a detailed evaluation of type 2 diabetes mellitus research output from 1951-2012, using large-scale data analysis, bibliometric indicators and density-equalizing mapping. Data were retrieved from the Science Citation Index Expanded database, one of the seven curated databases within Web of Science. Using Boolean operators "OR", "AND" and "NOT", a search strategy was developed to estimate the total number of published items. Only studies with an English abstract were eligible. Type 1 diabetes and gestational diabetes items were excluded. Specific software developed for the database analysed the data. Information including titles, authors’ affiliations and publication years were extracted from all files and exported to excel. Density-equalizing mapping was conducted as described by Groenberg-Kloft et al, 2008. A total of 24,783 items were published and cited 476,002 times. The greatest number of outputs were published in 2010 (n=2,139). The United States contributed 28.8% to the overall output, followed by the United Kingdom (8.2%) and Japan (7.7%). Bilateral cooperation was most common between the United States and United Kingdom (n=237). Harvard University produced 2% of all publications, followed by the University of California (1.1%). The leading journals were Diabetes, Diabetologia and Diabetes Care and they contributed 9.3%, 7.3% and 4.0% of the research yield, respectively. In conclusion, the volume of research is rising in parallel with the increasing global burden of disease due to type 2 diabetes mellitus. Bibliometrics analysis provides useful information to scientists and funding agencies involved in the development and implementation of research strategies to address global health issues

Reduced inclination of cervical spine in a novel notebook screen system : implications for rehabilitation

Background: Professional working at computer notebooks is associated with high requirements on the body posture in the seated position. By the high continuous static muscle stress resulting from this position at notebooks, professionals frequently working at notebooks for long hours are exposed to an increased risk of musculoskeletal complaints. Especially in subjects with back pain, new notebooks should be evaluated with a focus on rehabilitative issues. Methods: In a field study a new notebook design with adjustable screen was analyzed and compared to standard notebook position. Results: There are highly significant differences in the visual axis of individuals who are seated in the novel notebook position in comparison to the standard position. Also, differences are present between further alternative notebook positions. Testing of gender and glasses did not reveal influences. Conclusion: This study demonstrates that notebooks with adjustable screen may be used to improve the posture. Future studies may focus on patients with musculoskeletal diseases

Interfield dysbalances in research input and output benchmarking: Visualisation by density equalizing procedures

<p>Abstract</p> <p>Background</p> <p>Historical, social and economic reasons can lead to major differences in the allocation of health system resources and research funding. These differences might endanger the progress in diagnostic and therapeutic approaches of socio-economic important diseases. The present study aimed to assess different benchmarking approaches that might be used to analyse these disproportions. Research in two categories was analysed for various output parameters and compared to input parameters. Germany was used as a high income model country. For the areas of cardiovascular and respiratory medicine density equalizing mapping procedures visualized major geographical differences in both input and output markers.</p> <p>Results</p> <p>An imbalance in the state financial input was present with 36 cardiovascular versus 8 respiratory medicine state-financed full clinical university departments at the C4/W3 salary level. The imbalance in financial input is paralleled by an imbalance in overall quantitative output figures: The 36 cardiology chairs published 2708 articles in comparison to 453 articles published by the 8 respiratory medicine chairs in the period between 2002 and 2006. This is a ratio of 75.2 articles per cardiology chair and 56.63 articles per respiratory medicine chair. A similar trend is also present in the qualitative measures. Here, the 2708 cardiology publications were cited 48337 times (7290 times for respiratory medicine) which is an average citation of 17.85 per publication vs. 16.09 for respiratory medicine. The average number of citations per cardiology chair was 1342.69 in contrast to 911.25 citations per respiratory medicine chair. Further comparison of the contribution of the 16 different German states revealed major geographical differences concerning numbers of chairs, published items, total number of citations and average citations.</p> <p>Conclusion</p> <p>Despite similar significances of cardiovascular and respiratory diseases for the global burden of disease, large input and output imbalances have been revealed in the present study which point to a need for changes in funding policies. The present study supplies data that could be used for decision making in the field of health systems funding.</p