Aggregate vs disaggregate data analysis: a paradox in the estimation of money demand function of Japan under the low interest rate policy

We investigate the issue of whether there was a stable money demand function for Japan in 1990's using both aggregate and disaggregate time series data. The aggregate data appears to support the contention that there was no stable money demand function. The disaggregate data shows that there was a stable money demand function. Neither was there any indication of the presence of liquidity trapo Possible sources of discrepancy are explored and the diametrically opposite results between the aggregate and disaggregate analysis are attributed to the neglected heterogeneity among micro units. We also conduct simulation analysis to show that when heterogeneity among micro units is present. The prediction of aggregate outcomes, using aggregate data is less accurate than the prediction based on micro equations. Moreover. policy evaluation based on aggregate data can be grossly misleading.

Demand expectations and the timing of stimulus policies

This paper proposes a simple macroeconomic model with staggered investment decisions. The model captures the dynamic coordination problem arising from demand externalities and fixed costs of investment. In times of low economic activity, a firm faces low demand and hence has less incentives for investing, which reinforces firms’ expectations of low demand. In the unique equilibrium of the model, demand expectations are pinned down by fundamentals and history. Owing to the beliefs that arise in equilibrium, there is no special reason for stimulus at times of low economic activity.

Bias from ignoring price dispersion in demand estimation

Consumers often pay different prices for the same product bought in the same store at the same time. However, the demand estimation literature has ignored that fact using, instead, aggregate measures such as the “list” or average price. In this paper we show that this will lead to biased price coefficients. Furthermore, we perform simple comparative statics simulation exercises for the logit and random coefficient models. In the “list” price case we find that the bias is larger when discounts are higher, proportion of consumers facing discount prices is higher and when consumers are more unwilling to buy the product so that they almost only do it when facing discount. In the average price case we find that the bias is larger when discounts are higher, proportion of consumers that have access to discount are similar to the ones that do not have access and when consumers willingness to buy is very dependent on idiosyncratic shocks. Also bias is less problematic in the average price case in markets with a lot of bargain deals, so that prices are as good as individual. We conclude by proposing ways that the econometrician can reduce this bias using different information that he may have available.

Microinsurance: income risk, social security and the demand for private onsurance by low-income families

Insurance provision against uncertainties is present in several dimensions of peoples´s lives, such as the provisions related to, inter alia, unemployment, diseases, accidents, robbery and death. Microinsurance improves the ability of low-income individuals to cope with these risks. Brazil has a fairly developed financial system but still not geared towards the poor, especially in what concerns the insurance industry. The evaluation of the microinsurance effects on well-being, and the demand for different types of microinsurance require an analysis of the dynamics of the individual income process and an assessment of substitutes and complementary institutions that condition their respective financial behavior. The evaluation of the microinsurance effects on well-being, and the demand for different types of microinsurance require an analysis of the dynamics of the individual income process and an assessment of substitutes and complementary institutions that condition their respective financial behavior. The Brazilian government provides a relatively developed social security system considering other countries of similar income level which crowds-out the demand for insurance and savings. On the other hand, this same public infrastructure may help to foster microfinance products supply. The objective of this paper is to analyze the demand for different types of private insurance by the low-income population using microdata from a National Expenditure Survey (POF/IBGE). The final objective is to help to understand the trade-offs faced for the development of an emerging industry of microinsurance in Brazil.

Modelos matemáticos para estimativa do consumo máximo de oxigênio pela ventilometria de esforço em indivíduos saudáveis

The relation between metabolic demand and maximal oxygen consumption during exercise have been investigated in different areas of knowledge. In the health field, the determination of maximal oxygen consumption (VO2max) is considered a method to classify the level of physical fitness or the risk of cardiocirculatory diseases. The accuracy to obtain data provides a better evaluation of functional responses and allows a reduction in the error margin at the moment of risk classification, as well as, at the moment of determination of aerobic exercise work load. In Brasil, the use of respirometry associated to ergometric test became an opition in the cardiorespiratory evaluation. This equipment allows predictions concerning the oxyredutase process, making it possible to identify physiological responses to physical effort as the respiratory threshold. This thesis focused in the development of mathematical models developed by multiple regression validated by the stepwise method, aiming to predict the VO2max based on respiratory responses to physical effort. The sample was composed of a ramdom sample of 181 healthy individuals, men and women, that were randomized to two groups: regression group and cross validation group (GV). The voluntiars were submitted to a incremental treadmill test; objetiving to determinate of the second respiratory threshold (LVII) and the Peak VO2max. Using the método forward addition method 11 models of VO2max prediction in trendmill were developded. No significative differences were found between the VO2max meansured and the predicted by models when they were compared using ANOVA One-Way and the Post Hoc test of Turkey. We concluded that the developed mathematical models allow a prediction of the VO2max of healthy young individuals based on the LVII

Limnology of Macrobrachium amazonicum grow-out ponds subject to high inflow of nutrient-rich water and different stocking and harvest management

We evaluated the water characteristics and particle sedimentation in Macrobrachium amazonicum (Heller 1862) grow-out ponds supplied with a high inflow of nutrient-rich water. Prawns were subject to different stocking and harvesting strategies: upper-graded juveniles, lower-graded juveniles, non-graded juveniles + selective harvesting and traditional farming (non-grading juveniles and total harvest only). Dissolved oxygen, afternoon N-ammonia and N-nitrate and soluble orthophosphate were lower in the ponds in comparison with inflow water through the rearing cycle. Ponds stocked with the upper population fraction of graded prawns showed higher turbidity, total suspended solids and total Kjeldahl nitrogen than the remaining treatments. An increase in the chemical oxygen demand:biochemical oxygen demand ratio from inlet (4.9) to pond (7.1-8.0) waters indicated a non-readily biodegradable fraction enhancement in ponds. The sedimentation mean rate ranged from 0.08 to 0.16 mm day(-1) and sediment contained >80% of organic matter. The major factors affecting pond ecosystem dynamic were the organic load (due to primary production and feed addition) and bioturbation caused by stocking larger animals. Data suggest that M. amazonicum grow-out in ponds subjected to a high inflow of nutrient-rich water produce changes in the water properties, huge accumulation of organic sediment at the pond bottom and non-readily biodegradable material in the water column. However, the water quality remains suitable for aquaculture purposes. Therefore, nutrient-rich waters, when available, may represent a source of unpaid nutrients, which may be incorporated into economically valued biomass if managed properly.

Prevalência e fatores associados à dor em professores de educação física em academias de ginástica da cidade do Salvador-BA

Physical Education professionals are usually exposed to excessive physical workloads that evolve into painful symptomatology and muscle and bone disorders that originate from the work-related exercises. Purposo: The goal of this study was to investigate the prevalence and factors associated with pain painful symptomatology in teachers in gymnastics academies. An analytical transversal cut study was performed involving 163 gymnastics teachers working in the main gyms in the city of Salvador-BA. For evaluation of pain, validated versions in Portuguese of the McGill Protocol and the Wisconsin Pain Inventory were used. For obtain results of descriptive statistical analysis of the collected data was performed, followed by TStudent, and Pearson and Spearman correlation tests to verify possible correlations between the presence of pain and other variables which were considered independent. Finally, for the identification of potential risk factors associated with pain, a binary logistic regression analysis was performed. For all statistical analysis, we cnsidered p< 0.05. Results: The painful symptoms was reported by 88.3% of the subjects surveyed. High pain levels were observed in 63.8% of the interviewed professionals, where the intensity varied from moderate to severe. Pain in the lumbar region was present in 55.2% of subjects. Positive correlations were found between the level of pain intensity and the variables related with the workload activity and daily life of the teachers in almost all body joints analyzed. Some factors had been verified associates to the painful sintomatologia as the age of the professionals, the daily hours load of labor work, and the lack of interval of rest between the lessons. Conclusions: We found a high prevalence in gym teachers working in the city of Salvador-BA, which interfered in various daily activities of their home and professional lives. The most affected region was the lumbar region, followed by the knees, neck, shoulders, ankles, hands, hips, feet, elbows and forearms. The factors associated with development of painful symptomatology were the age of the professionals, daily hours of work and the lack of rest intervals between lessons. The high prevalence of pain in Physical Education teachers can be regarded as a serious occupational health problem, which would demand the urgent deployment of preventive intervention programs to minimize the impact of pain among these professionals

Backpacks and school children's obesity: challenges for public health and ergonomics

This descriptive study of cross sectional has focused on analyzing the school material weight transported by students associated with children and adolescents overweight in primary and secondary schools. Participants 339 students of both genders, aged 10-19 years. 243 students carrying and average load of 12.65% of his body weight. 53 students were overweight with a BMI of 20,00 to 35,6. 20 overweight students carrying backpacks more than 10% of his body weight. 21% of the students rated complained of back and shoulder pain. This data is very important in the preventive aspects for the individuals studied, as well as others with the same anthropometric characteristics and the same demand.

Carga de trabalho de enfermagem e infecções relacionadas à assistência à saúde na unidade de terapia intensiva

In recent decades, the search for quality care has been widely discussed by the institutions and health professionals. In this context, it is the nurse coordinator of the process of providing nursing staff, reflecting the commitment to quality of care. In this process, it is the appearance of Infections Related to health care and its potential association with the workload in nursing as a valuable indicator of quality of care. Thus, this research contributes to studies to characterize the demand of nursing work to promote a safe healthcare practice. This study aimed to identify the association of nursing workload with the number of cases of Ventilator-Associated Pneumonia, urinary tract infection and central venous catheter infection in the intensive care unit. This is a quantitative research approach, descriptive, cross-sectional and prospective, held at Unimed Hospital in Natal-RN. The study population consisted of all patients treated in the Intensive Care Unit, Hospital for a period of 90 consecutive days in 2011. The convenience sample was compostapelos patients admitted to the ICU during the period of data collection, a total sample of 286 patients. To perform the data analysis software were used: Statistica 6.0, SPPS (Statistical Package for Social Sciences) version 17.0 (2004) and Excel 2007. In the descriptive analysis, we used Measures of Central Tendency and Measures of Dispersion or Variability and the use of nonparametric tests. Of the 286 patients, 88 were from the ICU and 198 ICU II II. Males predominated in the ICU I (51.1%) and female ICU II (57.6%) patients in the ICU I were aged 61-80 years (39.8%) followed by greater than 80 years (39.8%). In the ICU II, most of the patients were aged 61-80 years (38.9%) and then from 41 to 60 years (24.2%). In relation to the class of TISS inlet predominant class II in the two ICUs (59.1%), followed by Class III also in the two units (34.6%). Most patients (70.6%) out of the ICUs belonging to class II TISS. In the ICU I, the average number of forms of the TISS 28 was 6, has in ICU II this value drops to 3.2 forms. The overall mean was 19.9 TISS points in ICU patients I and ICU II.the 17 points in the average hours required to provide adequate nursing care to patients in the ICU I found that is 10 , 7 hours, and the ICU II 9.2 hours. It was found that the time provided by the nursing staff were higher in ICU II, with an average of 19 hours available for nurses in this sector. In the ICU I, which showed higher need of available hours, it was found that the mean value of 12.7 available hours. It was found that only 2.4% of patients had these units Ventilator-Associated Pneumonia, 1.0% were infected central venous catheter and 1.4% of patients had urinary tract infection. Infection associated with health care occurs, on average, on the tenth day of hospitalization. In the ICU II, this average value extends to the twelfth day with an excess of 2.7 hours of nursing care while in ICU I value decays to the ninth day of hospitalization with a deficiency of 12-hour assistance. It is concluded that patients generally showed a need for classification of semi-intensive care and has been assisted in their need to load. As for his association with the Related Infections Health will assist this analysis could not be performed due to the small number of notifications in this period. It is suggested further study how other factors related to infections me a longer period of analysis

Prediction equations to estimate the demand of energy and crude protein for maintenance, gain and egg production for laying Japanese quails

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Um algoritmo para estimação de estado em alimentadores de distribuição de energia elétrica com base no método da soma de potências

Most algorithms for state estimation based on the classical model are just adequate for use in transmission networks. Few algorithms were developed specifically for distribution systems, probably because of the little amount of data available in real time. Most overhead feeders possess just current and voltage measurements at the middle voltage bus-bar at the substation. In this way, classical algorithms are of difficult implementation, even considering off-line acquired data as pseudo-measurements. However, the necessity of automating the operation of distribution networks, mainly in regard to the selectivity of protection systems, as well to implement possibilities of load transfer maneuvers, is changing the network planning policy. In this way, some equipments incorporating telemetry and command modules have been installed in order to improve operational features, and so increasing the amount of measurement data available in real-time in the System Operation Center (SOC). This encourages the development of a state estimator model, involving real-time information and pseudo-measurements of loads, that are built from typical power factors and utilization factors (demand factors) of distribution transformers. This work reports about the development of a new state estimation method, specific for radial distribution systems. The main algorithm of the method is based on the power summation load flow. The estimation is carried out piecewise, section by section of the feeder, going from the substation to the terminal nodes. For each section, a measurement model is built, resulting in a nonlinear overdetermined equations set, whose solution is achieved by the Gaussian normal equation. The estimated variables of a section are used as pseudo-measurements for the next section. In general, a measurement set for a generic section consists of pseudo-measurements of power flows and nodal voltages obtained from the previous section or measurements in real-time, if they exist -, besides pseudomeasurements of injected powers for the power summations, whose functions are the load flow equations, assuming that the network can be represented by its single-phase equivalent. The great advantage of the algorithm is its simplicity and low computational effort. Moreover, the algorithm is very efficient, in regard to the accuracy of the estimated values. Besides the power summation state estimator, this work shows how other algorithms could be adapted to provide state estimation of middle voltage substations and networks, namely Schweppes method and an algorithm based on current proportionality, that is usually adopted for network planning tasks. Both estimators were implemented not only as alternatives for the proposed method, but also looking for getting results that give support for its validation. Once in most cases no power measurement is performed at beginning of the feeder and this is required for implementing the power summation estimations method, a new algorithm for estimating the network variables at the middle voltage bus-bar was also developed

PCJ River Basins' Water Availability Caused by Water Diversion Scenarios to Supply Metropolitan Areas of So Paulo

Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)

Maximização da penetração da geração distribuída através do algoritmo de otimização nuvem de partículas

This work develops a methodology for defining the maximum active power being injected into predefined nodes in the studied distribution networks, considering the possibility of multiple accesses of generating units. The definition of these maximum values is obtained from an optimization study, in which further losses should not exceed those of the base case, i.e., without the presence of distributed generation. The restrictions on the loading of the branches and voltages of the system are respected. To face the problem it is proposed an algorithm, which is based on the numerical method called particle swarm optimization, applied to the study of AC conventional load flow and optimal load flow for maximizing the penetration of distributed generation. Alternatively, the Newton-Raphson method was incorporated to resolution of the load flow. The computer program is performed with the SCILAB software. The proposed algorithm is tested with the data from the IEEE network with 14 nodes and from another network, this one from the Rio Grande do Norte State, at a high voltage (69 kV), with 25 nodes. The algorithm defines allowed values of nominal active power of distributed generation, in percentage terms relative to the demand of the network, from reference values

Caracterização do efluente líquido no processo de beneficiamento do índigo têxtil

The great diversity of the textile industries activities causes the formation of wastewaters with high complex characteristics during the productive process, according to the industrial process used. The principal aim of the present work is the characterization of the wastewater from the textile industry that process the indigo, located in the Industrial District of Natal-RN, to know the contaminante load of each stage of the process and the framing of the wastewater with the standards of act of receiving of the System of Treatment of Wastewater of the Industrial District of Natal-RN SITEL-DIN, operated for the Company of Waters and Sewers of the RN CAERN. It was analyzed the following properties and pollutants agents: temperature; pH; alcalinity; color; COD (Chemical Oxygen Demand); total and suspended solids; heavy metals, thermotolerants coliformes, turbidity, dissolved oxygen and electrical conductivity. As conclusion it is distinguished that the wastewater did not get resulted satisfactory, according to comparisons with other sources, in only three parameters: turbidity, dissolved oxygen and electrical conductivity, however none of these parameters is criteria of acts of receiving of the SITEL-DIN,therefore the wastewater if finds inside of normality. After the analysis of the obtained results it was verified that SITEL-DIN is indispensable for completing the wastewater treatment

Caracterização de escovas de grafite e avaliação do seu desempenho em função da microestrutura

The electric can be converted into thermal, luminous, electromagnetic, and also in mechanical energy. In this context the electric engines plays a fundamental role, specially that they work very below of its nominal capacity, with consequent decrease load density. In industrial environment, these characteristics of work of DC engines had also generated an extreme consumption of coal brushs and attack in the commutator reducing the useful life of the engine and increasing maintenance demand and cost. The general objective of the present work is to study the influence of the granulometry of the coal brush used in DC engines with the resistance to the consumption of the same ones, as well as in the performance presented by the commutator of the engine. Additionally, determining the measurable and not measurable profits when the brush used is adjusted to the application. The brushes had been produced by an industry of the sector and tested in industrial environment to evaluate their performance and consumption. Preliminary results evidence a substantial improvement in the performance of these brushes in function of its microstructure and the application in which it is used