Integrated bio-economic models as tools to support land-use decision making: a review of potential and limitations

Bio-economic modelling has become a useful tool for anticipating the outcomes of policies and technologies before their implementation. Advances in mathematical programming have made it possible to build more comprehensive models. In an overview of recent studies about bio-economic models applied to land-use problems in agriculture and forestry, we evaluated how aspects such as uncertainty, multiple objective functions, system dynamics and time have been incorporated into models. We found that single objective models were more frequently applied at the farm level, while multiple objective modelling has been applied to meet concerns at the landscape level. Among the objectives, social aspects are seldom represented in all models, when being compared to economic and environmental aspects. The integration of uncertainty is occasionally a topic, while stochastic approaches are more frequently applied than non-stochastic robust methods. Most multiple-objective models do not integrate uncertainty or sequential decision making. Static approaches continue to be more recurrent than truly dynamic models. Even though integrating multiple aspects may enhance our understanding of a system; it involves a tradeoff between complexity and robustness of the results obtained. Land-use models have to address this balance between complexity and robustness in order to evolve towards robust multiple-objective spatial optimization as a prerequisite to achieve sustainability goals.     

An alternative interpretation of multiple bounded WTP data—Certainty dependent payment card intervals

This paper analyzes the multiple bounded format, in which uncertainty is directly incorporated into the WTP question. A new approach for analyzing multiple bounded uncertainty data is presented. The intuition underlying the approach is that uncertain individuals would like to state their WTP as intervals rather than precise values and that the width of the intervals is determined by the degree of uncertainty. The approach is compared to the one applied in Welsh and Poe [Welsh, M., Poe, G.L., 1998. Elicitation effects in contingent valuation: comparisons to a multiple bounded discrete choice approach. Journal of Environmental Economics and Management 36, 170–185] which treats uncertainty by conditioning responses on specific verbal probability statements. We argue that the conditioning approach overestimates mean and median WTP and that conditioning WTP estimates on probability statements like “probably” and “unsure” make them “fuzzy”. To empirically compare the two approaches we use data from 2004 concerning implementation of a predator protection policy in Sweden. Our analysis show that the suggested approach: (1) is more intuitive; (2) better fits the data; (3) estimates mean and median WTP with better precision; (4) is less sensitive to distributional assumptions; and (5) it is better suited for policy analysis.     

Multilateral Reforms of Trade and Environmental Policy

The paper analyzes environmental tax policy reform using a competitive model of world trade that includes production‐generated environmental damage (pollution) and trade tariffs. The authors examine the feasibility of Pareto‐improving multilateral reforms of environmental taxes, and show that any environmental tax reform that is mutually welfare‐improving when compensating lump‐sum transfers are assumed is also welfare‐improving when a suitable tariff reform (but no transfers) is combined with the tax changes. Several specific reform proposals are developed. These results expand the feasible set of mutually improving policy proposals for international policy initiatives.     

The effects of debt versus equity inflows on savings and growth in developing economies

Zusammenfassung Die Wirkung von ausl?ndischer Kapitalbeteiligung und Kreditfinanzierung auf Ersparnisbildung und Wachstum in Entwicklungsl?ndern. — Zur Bew?ltigung der internationalen Schuldenprobleme von Entwicklungsl?ndern wird h?ufig vorgeschlagen, die Struktur des Kapitalimports zugunsten von Forderungsarten zu verschieben, bei denen sich die Gl?ubiger am wirtschaftlichen Risiko beteiligen, wie dies etwa bei Direktinvestitionen der Fall ist. Die Wahl zwischen Kapitalbeteiligung und Kreditfinanzierung mag jedoch Risiko-Ertrag-Konflikte zwischen Einkommensstabilit?t und erwartetem wirtschaftlichem Wachstum involvieren. Diese Hypothese wird aus einem entscheidungstheoretischen Modell auf der Basis eines Benutzer-Eigentümer Verh?ltnisses abgeleitet und mittels einer L?nderquerschnittsuntersuchung regressionsanalytisch getestet. Es zeigt sich, da\ bei nichtkooperativen Beziehungen zwischen Schuldnern und Gl?ubigern kreditfinanzierte Kapitalimporte einen vergleichsweise starken positiven Einflu\ auf die Ersparnisbildung und das Wirtschaftswachtum im Schuldnerland ausüben. Kapitalbeteiligungen k?nnen deshalb nicht ohne weiteres als vorteilhaft angesehen werden und auch nicht allen L?ndern empfohlen werden, ohne zu bedenken, wie sich soziale Gruppen gegenüber dem Risiko verhalten.

---

Résumé Les effets de l’influx de la dette et du capital propre sur l’épargne et la croissance en économies développantes. — L’élément commun des beaucoup de propositions données pour faciliter les problèmes de la dette extérieure des pays développants est l’intention de changer la structure des importations de capital vers l’augmentation du rapport des créances qui basent sur quelque forme de partager les risques, p.e. la participation en capital propre. Cependant, le choix entre le capital propre ou des influx des capitaux financés par des dettes peut induire un conflit de ?rendement-risque? entre la stabilité de revenu et la croissance attendue. Cette hypothèse est dérivée d’un modèle choix-théorique basé sur l’approche agent-principal et testée empiriquement en appliquant l’analyse de régression trans-pays. Les auteurs démontrent que, dans un cadre non-coopératif des relations débiteurcréditeur, des transferts financés par des dettes ont une influence plus positive sur l’épargne et la croissance économique. La participation en capital propre ne peut pas être évaluée supérieure sans ambigu?té et c’est pourquoi elle ne peut pas être recommendée pour tous les pays, indépendant des attitudes sociales envers le risque.

---

Resumen El efecto del endeudamiento sobre el ahorro y el crecimiento eneconomías en desarrollo comparado con el de las inversiones directas. — En varias propuestas para aliviar el problema de la deuda externa de los países en desarrollo se sugiere alterar la composición de las importaciones de capital en el sentido de aumentar la proportión de derechos con participación en el riesgo económico, es decir, la participación de la inversión directa. La elección entre inversión directa y deuda considera la relación inversa riesgo-beneficio que existe entre la estabilidad del ingreso y el crecimiento esperado. Esta tesis se dériva de un modelo teórico de elección basado en el enfoque agente-principal, que es sometido a un test empírico de regresión sobre una muestra de países. Se muestra que en el marco de relaciones deudor-acreedor de tipo no cooperativas las transferencias de financiamiento por deuda ejercen una influencia positiva relativamente superior sobre el ahorro y el crecimiento económico. La participación directa en el capital no resulta superior en todos casos y por ello no puede ser recomendada para todos los países, independientemente de las actitudes frente al riesgo que prevalezcan.

     

The division of labour and market structure

Most firms produce most of the time under conditions of substantial economies of scale. The division of labour, according to Adam Smith the mainspring of wealth, is intrinsically an economies of scale phenomenon. Market structure in most industries in characterized by a small number of suppliers and a larger number of customers. I explain this law of small numbers as the equilibrium of two forces: the deconcentration effect of imitation and the market spliting effect of further refinements in the division of labour by innovation. A deconcentrated market creates larger incentives for market splitting (product differentiation) by innovation than a concentrated market. But market splitting raises concentration in the market and it raises the number of different markets in the economy. Before the economies of scale of old products are fully exploited, new products are being offered which again are produced under conditions of economies of scale.     

Complementarity, growth, and trade

We consider an endogenous growth model with international trade in complementary capital goods. The model possesses several distinct, balanced growth solutions, which we classify using stability under adaptive learning. Some of the equilibria can involve growth rates much higher than others. We show that, in addition to a small (usually positive) effect on a given equilibrium, an expansion in trade may sometimes yield a much larger, sudden jump in growth. The small effect on the initial equilibrium may reduce growth if the opportunity cost of capital rises very fast as growth accelerates. JEL Classification: F12, F15, O41
Complémentarité, croissance, et commerce international. Les auteurs utilisent un modèle de croissance endogène en présence de commerce international de biens capitaux complémentaires. Le modèle possède plusieurs solutions de croissance équilibrée distinctes que les auteurs classifient en utilisant des mesures de stabilité avec apprentissage adaptatif. Certains de ces équilibres peuvent impliquer des taux de croissance plus élevés que d'autres. Il appert qu'une expansion du commerce international, en plus d'avoir un petit effet (habituellement positif) sur un équilibre donné, peut parfois engendrer une augmentation plus forte et soudaine de la croissance. Le petit effet sur l'équilibre initial peut réduire la croissance si le coût d'opportunité du capital augmente rapidement à proportion que la croissance accélère.     

Some economics of content protection

We are grateful to a perceptive referee for many constructive comments on an earlier version of this paper entitled The Economics of Content Protection: A Dual Approach. The usual disclaimer applies.