Knowledge Accumulation within an Organization

We develop a simple model of task allocation for knowledge workers over their career within an organization. The human capital theory initiated by Becker (1962, 1964) has o¤ered a rich analysis of an individuals life cycle investment in human capital. One of the main result of this literature states that human capital investments are undertaken at the early stage of the career because workers have then a longer period of time over which they can bene…t from the return of their investments. In this paper, we consider a knowledge accumulation problem within an organization that cannot prevent the worker from quitting and using the knowledge outside the organization. In the …rst best situation, we show a similar result as in the human capital theory, i.e. the share of time allocated to knowledge creation tasks decreases over time. We then ask how this pattern is a¤ected when the knowledge worker can leave the organization and bene…t from this knowledge outside the organization. In this case, we obtain the novel result that the time path of the fraction of working time allocated to knowledge creation tasks is non-monotone. This fraction is highest at the early career stage, falls gradually, then rises again, before falling …nally toward zero. We also show that an increase in the …rm-speci…city of knowledge can increase or decrease the life-time income of the knowledge worker.

Environmental policy and directed technological change: evidence from the European carbon market

This paper investigates the impact of the European Union Emissions Trading System (EU ETS) on technological change, exploiting installations-level inclusion criteria to estimate the System's causal impact on firms' patenting. We find that the EU ETS has increased low-carbon innovation among regulated firms by as much as 10%, while not crowding out patenting for other technologies. We also find evidence that the EU ETS has not impacted patenting beyond the set of regulated companies. These results imply that the EU ETS accounts for nearly a 1% increase in European low-carbon patenting compared to a counterfactual scenario

Environmental Policy and Directed Technological Change: Evidence from the European Carbon Market

This paper investigates the impact of the EU Emissions Trading Scheme (EU ETS) on technological change. We exploit installations-level inclusion criteria to estimate the impact of the EU ETS on firms patenting. We find that the EU ETS has increased low-carbon innovation among regulated firms by as much as 10%, while not crowding out patenting for other technologies. We also find evidence that the EU ETS has not impacted patenting beyond the set of regulated companies. These results imply that the EU ETS accounts for nearly a 1% increase in European lowcarbon patenting compared to a counterfactual scenario

About the Blaschke-Santalo diagram of area, perimeter and moment of inertia

We study the Blaschke-Santal\'o diagram associated to the area, the perimeter, and the moment of inertia. We work in dimension 2, under two assumptions on the shapes: convexity and the presence of two orthogonal axis of symmetry. We discuss topological and geometrical properties of the diagram. As a by-product we address a conjecture by P\'olya, in the simplified setting of double symmetry

Policing carbon markets

Carbon markets have emerged in recent decades as one of the most important tools for curbing industrial greenhouse gas emissions, but they present a number of novel enforcement challenges as compared to more conventional pollution regulations—new regulators with narrow authority, lack of legal precedent, and more. To shed light on the practical issues involved in policing carbon markets, we present the first comprehensive analysis of the EU Emissions Trading System, a single program that was policed by 31 different national regulators. We find generally high rates of compliance coupled with low rates of enforcement, a pattern that is known in the literature as ‘Harrington’s paradox.’ Variation in the probability and severity of fines explain just one tenth of the variation in compliance rates. Meanwhile, other enforcement strategies that have been pointed to as resolutions to Harrington’s paradox in other applications, such as ‘naming and shaming,’ appear to have had little discernible effect

Predicting pedestrian trajectories at different densities: A multi-criteria empirical analysis

Predicting human trajectories is a challenging task due to the complexity of pedestrian behavior, which is influenced by external factors such as the scene's topology and interactions with other pedestrians. A special challenge arises from the dependence of the behaviour on the density of the scene. In the literature, deep learning algorithms show the best performance in predicting pedestrian trajectories, but so far just for situations with low densities. In this study, we aim to investigate the suitability of these algorithms for high-density scenarios by evaluating them on different error metrics and comparing their accuracy to that of knowledge-based models that have been used since long time in the literature. The findings indicate that deep learning algorithms provide improved trajectory prediction accuracy in the distance metrics for all tested densities. Nevertheless, we observe a significant number of collisions in the predictions, especially in high-density scenarios. This issue arises partly due to the absence of a collision avoidance mechanism within the algorithms and partly because the distance-based collision metric is inadequate for dense situations. To address these limitations, we propose the introduction of a novel continuous collision metric based on pedestrians' time-to-collision. Subsequently, we outline how this metric can be utilized to enhance the training of the algorithms

Roadmap for daily practice of CBCT in cleft lip palate paediatric patients: a pictorial review.

Objective: to present and to illustrate a new methodology for daily practice in cone beam computed tomography (CBCT) interpretation and reporting in cleft lip palate (CLP) non syndromic paediatric patients. The proposed protocol is based on clinical experience and on systematic search of the literature. Material and methods: We performed two types of systematic search of articles: 1) articles related to the use of CBCT in CLP patients, and 2) articles related to the reporting and interpretation of the CBCT images by radiologists. We used two databases PubMed and Google scholar. Results: For indications of CBCT in CLP patients we found in PubMed 378 articles and 48 articles were selected for the review; in Google scholar we found 463 articles, and 9 articles were selected for the review. 2) For reporting in CBCT we found 956 articles in PubMed, and 9 articles were selected for the review. Conclusions: We presented the 6-steps system for interpretation and reporting information from CBCT of CLP paediatric patients: 1) Step 1 (axial view): presence or absence of bone bridge remnants of alveolar bone graft; Step 2 (3D dental tissue reconstruction): description of dental arch tooth by tooth, search for agenesis and supernumerary teeth, description of variation in the position of the tooth explaining the type of existing translation and rotation; Step 3 (coronal view): cleft palate pathway and its extension; anomaly in maxillary, ethmoid and sphenoid sinuses if existing; Step 4 (sagittal and coronal view): checking of the opening (calcification sites) of the sphenooccipital synchondrosis, and checking of anomalies of the occipital bone; Step 5 (3D bone tissue reconstruction): C1-C2 vertebra anomalies; Step 6 (3D soft tissue reconstruction): external ear anomalies. We illustrated our methodology with 46 figures from 5 CBCT of CLP patients.Objective: to present and to illustrate a new methodology for daily practice in cone beam computed tomography (CBCT) interpretation and reporting in cleft lip palate (CLP) non syndromic paediatric patients. The proposed protocol is based on clinical experience and on systematic search of the literature. Material and methods: We performed two types of systematic search of articles: 1) articles related to the use of CBCT in CLP patients, and 2) articles related to the reporting and interpretation of the CBCT images by radiologists. We used two databases PubMed and Google scholar. Results: For indications of CBCT in CLP patients we found in PubMed 378 articles and 48 articles were selected for the review; in Google scholar we found 463 articles, and 9 articles were selected for the review. 2) For reporting in CBCT we found 956 articles in PubMed, and 9 articles were selected for the review. Conclusions: We presented the 6-steps system for interpretation and reporting information from CBCT of CLP paediatric patients: 1) Step 1 (axial view): presence or absence of bone bridge remnants of alveolar bone graft; Step 2 (3D dental tissue reconstruction): description of dental arch tooth y tooth, search for agenesis and supernumerary teeth, description of variation in the position of the tooth explaining the type of existing translation and rotation; Step 3 (coronal view): cleft palate pathway and its extension; anomaly in maxillary, ethmoid and sphenoid sinuses if existing; Step 4 (sagittal and coronal view): checking of the opening (calcification sites) of the sphenooccipital synchondrosis, and checking of anomalies of the occipital bone; Step 5 (3D bone tissue reconstruction): C1-C2 vertebra anomalies; Step 6 (3D soft tissue reconstruction): external ear anomalies. We illustrated our methodology with 46 figures from 5 CBCT of CLP patients

Time-continuous microscopic pedestrian models: an overview

We give an overview of time-continuous pedestrian models with a focus on data-driven modelling. Starting from pioneer, reactive force-based models we move forward to modern, active pedestrian models with sophisticated collision-avoidance and anticipation techniques through optimisation problems. The overview focuses on the mathematical aspects of the models and their different components. We include methods used for data-based calibration of model parameters, hybrid approaches incorporating neural networks, and purely data-based models fitted by deep learning. Some development perspectives of modelling paradigms we expect to grow in the coming years are outlined in the conclusion.Comment: 26 pages; chapter accepted for publication in Crowd Dynamics (vol. 4

Do carbon offsets offset carbon?

We develop and implement a new method for identifying wasted subsidies, and use it to provide systematic evidence on the misallocation of carbon offsets in the Clean Development Mechanism - the world's largest carbon offset program. Using newly constructed data on the locations and characteristics of 1,350 wind farms in India - a context where it was believed, ex-ante, that the Clean Development Mechanism could significantly increase development above baseline projections - we estimate that at least 52% of approved carbon offsets were allocated to projects that would very likely have been built anyway. In addition to wasting scarce resources, we estimate that the sale of these offsets to regulated polluters has substantially increased global carbon dioxide emissions

Initiating Lane and Band Formation in Heterogeneous Pedestrian Dynamics

Self-avoiding agents such as pedestrians or road vehicles can exhibit different types of collective and coordinated dynamics. Prominent examples are stop-and-go waves and lane formation, or nonuniform patterns and ordered structures at bottlenecks and intersections. Non-linear effects, phase transitions, and metastability in the collective dynamics of interacting agents raise interesting theoretical questions. Besides scientific interests, understanding and controlling collective performances from individual interaction rules is fundamental to authorities. In this contribution, we show using a two-species agent-based model that heterogeneity can generically initiate segregation and spontaneous formation of lanes and bands. Two universal heterogeneity mechanisms are identified. In the first one, we attribute statically two different values to the parameters of the two types of agents. We aim here to model static heterogeneous individual characteristics. In the second model, we attribute dynamically two different values for the parameters according to the type of the closest agent in front. In contrast to the first model for which the heterogeneity lies statically in agent characteristics, we aim to model dynamic heterogeneity in the interactions. Simulation results show that self-organized lane and band formations spontaneously occur when the heterogeneity factors are sufficiently high. More precisely, we observe the emergence of longitudinal lanes when the heterogeneity lies in the agents when transversal bands arise if we assume heterogeneity in the interactions. The different organizations of the flow highly influence the system's performance. Lane patterns significantly improve the flow, while band formation acting as gridlocks result in lower performance