Centralized common pool management and local community participation

cooperative games

Nonresponse and Focal Point Answers to Subjective Probability Questions

We develop and estimate a panel data model explaining the answers to questions about subjective probabilities, using data from the US Health and Retirement Study. We explicitly account for nonresponse, rounding, and focal point “50 percent” answers. Our results indicate that for three of the four questions considered, almost all 50 percent answers can be explained by rounding. We also find observed and unobserved heterogeneity in the tendencies to report rounded values or a focal answer, explaining persistency in 50 percent-answers over time. Incorporating rounding and focal answers changes some of the conclusions about the socio-economic factors that determine expectations.item nonresponse, rounding, expectations

Comparing predictions and outcomes: theory and application to income changes.

Household surveys often elicit respondents' intentions or predictions of future outcomes. The survey questions may ask respondents to choose among a selection of (ordered) response categories. If panel data or repeated cross-sections are available, predictions may be compared with realized outcomes. The categorical nature of the predictions data, however, complicates this comparison. Generalizing previous findings on binary intentions data, we derive bounds on features of the empirical distribution of realized outcomes under the "best-case" hypothesis that respondents form rational expectations and that reported expectations are best predictions of future outcomes. These bounds are shown to depend on the assumed model of how respondents form their "best prediction" when forced to choose among (ordered) categories. An application to data on income change expectations and realizations illustrates how alternative response models may be used to test the best-case hypothesis.

Comparing Predictions and Outcomes: Theory and Application to Income Changes

Household surveys often elicit respondents' intentions or predictions of future outcomes. The survey questions may ask respondents to choose among a selection of (ordered) response categories. If panel data or repeated cross-sections are available, predictions may be compared with realized outcomes. The categorical nature of the predictions data, however, complicates this comparison. Generalizing previous findings on binary intentions data, we derive bounds on features of the empirical distribution of realized outcomes under the "best-case" hypothesis that respondents have rational expectations and that reported expectations are best predictions of future outcomes. These bounds are shown to depend on the assumed model of how respondents form their "best prediction" when forced to choose among (ordered) categories. An application to data on income change expectations and realized income changes illustrates how alternative response models may be used to test the best-case hypothesis.predictions;categorical data;loss function;income growth

Threshold effects of energy price changes

This paper presents a theoretical model emphasising energy investments’characteristics of uncertainty and irreversibility. The theoretical modelsuggests threshold effects. Firms are induced to substitute away from energyonly if prices of energy exceed a certain threshold level and they reverse thetechnology only if energy prices are low enough. Estimating a simpleinvestment relation using panel data for the Dutch economy, we findevidence for threshold effects.

Sponges of the family Esperiopsidae (Demospongiae, Poecilosclerida) from Northwest Africa, with the descriptions of four new species

Sponges belonging to the genera Amphilectus Vosmaer, Esperiopsis Carter and Ulosa de Laubenfels of the family Esperiopsidae were collected during 1986 and 1988 expeditions of the Netherlands Centre for Biodiversity Naturalis (at that time the National Museum of Natural History at Leiden and the Zoological Museum of Amsterdam) in waters off the coasts of Mauritania and the Cape Verde Islands. Four new species, Amphilectus utriculus sp. nov., Amphilectus strepsichelifer sp. nov., Esperiopsis cimensis sp. nov., Ulosa capblancensis sp. nov., and two already known species, Amphilectus cf. fucorum (Esper) and Ulosa stuposa (Esper) are described and discussed

Alignment issues in photonic crystal device fabrication

An important requirement in the fabrication of photonic crystal structures is the correct relative alignment of structural elements. Accuracy should be in the order of some tens of nanometres. Some of the options for providing such accuracy are discussed. Examples are given of aligning defects with respect to a predefined 2D lattice, aligning access waveguides with respect to a small local photonic crystal structure, and the alignment of successive periodically structured layers in a 3D "woodpile" structure

Economc Ties and Social Dilemmas: An Experimental Study

common-pool resources;peer enforcement;selective exclusion;experiment

Threshold effects of energy price changes

This paper presents a theoretical model emphasising energy investments’characteristics of uncertainty and irreversibility. The theoretical modelsuggests threshold effects. Firms are induced to substitute away from energyonly if prices of energy exceed a certain threshold level and they reverse thetechnology only if energy prices are low enough. Estimating a simpleinvestment relation using panel data for the Dutch economy, we findevidence for threshold effects