Parallel implementation of the TRANSIMS micro-simulation

This paper describes the parallel implementation of the TRANSIMS traffic micro-simulation. The parallelization method is domain decomposition, which means that each CPU of the parallel computer is responsible for a different geographical area of the simulated region. We describe how information between domains is exchanged, and how the transportation network graph is partitioned. An adaptive scheme is used to optimize load balancing. We then demonstrate how computing speeds of our parallel micro-simulations can be systematically predicted once the scenario and the computer architecture are known. This makes it possible, for example, to decide if a certain study is feasible with a certain computing budget, and how to invest that budget. The main ingredients of the prediction are knowledge about the parallel implementation of the micro-simulation, knowledge about the characteristics of the partitioning of the transportation network graph, and knowledge about the interaction of these quantities with the computer system. In particular, we investigate the differences between switched and non-switched topologies, and the effects of 10 Mbit, 100 Mbit, and Gbit Ethernet. keywords: Traffic simulation, parallel computing, transportation planning, TRANSIM

Statistical Inference in Micro Simulation Models: Incorporating external information

In practical applications of micro simulation models very little is usually known about the properties of the simulated values. This paper argues that we need to apply the same rigorous standards for inference in micro simulation work as in scientific work generally. If not, then micro simulation models will loose in credibility. The paper first discusses how the structure of the model will determine inference and then follow sections on estimation and validation. Differences between inference in static and dynamic models are noted and then the paper focuses on the estimation of behavioral parameters. There are three themes: calibration viewed as estimation subject to external constraints, piece meal vs. system-wide estimation, and simulation based estimation.Micro simulation; Alignment; Calibration; System-wide estimation; Simulation-based estimation

Learning-Testing Process in Classroom: An Empirical Simulation Model

This paper presents an empirical micro-simulation model of the teaching and the testing process in the classroomH. It is a non-econometric micro-simulation model describing informational behaviors of the pupils, based on the observation of the pupils’ communication behavior during lessons and tests. The representation of the knowledge process is very simplified. However, we tried to study the involvements of individual motivation, capability and relationship with other pupils of each pupil, to compare them to the new-classical(and keynesian) and Austrian information and knowledge theoretical results. It is a first step and future development should concern expectation behaviors and dynamics. This paper aims too to give, we hope so, some criteria of pupils’ rationality in the classroom.Teaching ; Learning ; Cheating ; Information ; Communication ; Knowledge ; Micro-simulation ; Classroom

A Computable General Equilibrium Micro-Simulation Analysis of the Impact of Trade Policies on Poverty in Zimbabwe

The paper uses a micro-simulation computable general equilibrium (CGE) model to study the impact on poverty of a complete removal of tariffs in Zimbabwe. The model incorporates 14006 households derived from the 1995 Poverty Assessment Study Survey. This paper’s novelty is that it is one among a small group of papers that incorporates individual households in the CGE model as opposed to having representative households. Using individual households allows for a comprehensive analysis of poverty. The complete removal of tariffs favours exporting sectors. Poverty falls in the economy while inequality hardly changes. The results differ between rural and urban areas.Computable General Equilibrium, Trade Liberalisation, Micro-simulation, Poverty, Inequality

Micro-Simulation of Social Security Reforms in Belgium

The present paper analyzes the budgetary impact of various Social Security reforms in the Belgian institutional setting. Our approach relies on parameters that were derived in Dellis et alii (2002) using a micro-modeling strategy. focusing our attention on a hypothetical age cohort, we illustrate the budgetary impact that the reforms considered might have on the budget of the federal government.

Computable General Equilibrium Micro-Simulation Analysis of the Impact of Trade Policies on Poverty in Zimbabwe

The paper uses a micro-simulation computable general equilibrium (CGE) model to study the impact on poverty of trade liberalisation in Zimbabwe. The model incorporates 14006 households derived from the 1995 Poverty Assessment Study Survey (PASS). The novelty of this paper is that it is one among a small group of papers that incorporates individual households in the CGE model as opposed to having representative households, allowing for a comprehensive analysis of poverty. The complete removal of tariffs favours export-oriented sectors and all imports increase. Poverty falls in the economy while inequality hardly changes. The results differ between rural and urban areas.Computable General Equilibrium, Trade Liberalisation, Micro-simulation, Poverty, Inequality

Modelling Private Wealth Accumulation and Spend-down in the Italian Microsimulation Model CAPP_DYN: A Life-Cycle Approach

In microsimulation literature a limited number of models include a module aimed at analyzing and projecting the evolution of privat e wealth over time. However, this issue appears crucial in order to comprehensively evaluate the li kely distributional effects of institutional reforms adopted to cope with population ageing. In this work we describe the implementation in the Italian dynamic micro simulation model CAPP_DYN of a new module in which households\u2019 savings and asset allocation are modelled. In parti cular, we aim to account for possible behavioural responses to pension reforms in househo ld savings. To this end, we rely on an approximate life cycle structural framework for est imating saving behaviour, while adopting a traditional stochastic micro simulation approach fo r asset allocation. In line with Ando and Nicoletti Altimari (2004), we emphasize the role of lifetime economic resources in households\u2019 consumption decisions, yet we further account for i nternal habit formation and subjective expectations on pension outcomes in the econometric stage. In addition, we model intergenerational transfers of private wealth in a probabilistic fashio

Poverty and Income Distribution in a CGE-Household Micro-Simulation Model: Top-Down/Bottom Up Approach

This paper highlights the idea of combining CGE modeling with a micro-household model (micro-simulation) to generate a convergent solution, thus providing the basis to perform counterfactual analysis of trade and fiscal policies, and their impact on poverty. In recent years, a number of papers have presented differen approaches using CGE models to analyze poverty. Among them, the standard CGE models, which generates changes in the income of representative households in order to allow poverty analysis, albeit with no intra-group changes in the distribution; CGE models with high levels of household disaggregation (3200) and the micro-simulation approach to modeling (with no feedback effect to the CGE model). In this paper, we provide an alternative to these methods that allows a richer micro-household modeling than the first two approaches, while keeping the properties of standard CGE (feedback effect of household behavior) which is usually simplified in micro-simulation context. We also introduce segmented labor markets, with waiting unemployment, inspired by Magnac (1991), which provides a basis for important changes in household income (i.e. when a worker leaves unemployment or becomes unemployed). Global and decomposable poverty analysis and income distribution indicators are computed at base year and after a 50% reduction in trade.Computable general equilibrium models, estimation, personal income and wealth distribution, measurement and analysis of poverty

The dynamics of iterated transportation simulations

Iterating between a router and a traffic micro-simulation is an increasibly accepted method for doing traffic assignment. This paper, after pointing out that the analytical theory of simulation-based assignment to-date is insufficient for some practical cases, presents results of simulation studies from a real world study. Specifically, we look into the issues of uniqueness, variability, and robustness and validation. Regarding uniqueness, despite some cautionary notes from a theoretical point of view, we find no indication of ``meta-stable'' states for the iterations. Variability however is considerable. By variability we mean the variation of the simulation of a given plan set by just changing the random seed. We show then results from three different micro-simulations under the same iteration scenario in order to test for the robustness of the results under different implementations. We find the results encouraging, also when comparing to reality and with a traditional assignment result. Keywords: dynamic traffic assignment (DTA); traffic micro-simulation; TRANSIMS; large-scale simulations; urban planningComment: 24 pages, 7 figure