The elusive quest for additionality

Development finance institutions (DFIs) annually invest $90 billion to support under-financed projects across the world. Although these government-backed institutions are often asked to show that their investments are “additional” to what private investors would have financed, it is rarely clear what evidence is needed to answer this request. This paper demonstrates, through a series of simulations, that the nature of DFIs’ operations creates systematic biases in how a range of estimators assess additionality. Recognising that rigorous quantitative evidence of additionality may continue to elude us, we discuss the value of qualitative evidence, and propose a probabilistic approach to evaluating additionality

Acute occupational phosphine intoxications : a retrospective study by the Belgian Poison Centre

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An integrated process for planning, delivery, and stewardship of urban nature-based solutions: the Connecting Nature Framework

Mainstreaming nature-based solutions in cities has grown in scale and magnitude in recent times but is still considered to be the main challenge for transitioning our cities and their communities to be more climate resilient and liveable: environmentally, economically, and socially. Furthermore, taking nature-based solutions to the next level, and scaling them out to all urban contexts to achieve a greater impact, is proving to be slow and often conflicts with other transitioning initiatives such as energy generation, mobility and transport initiatives, and infilling to combat sprawl. So, the task is neither easy nor straightforward; there are many barriers to this novel transition, especially when it comes to collaborative approaches to implementing nature-based solutions with diverse urban communities and within city authorities themselves. This paper reports on a new process that is systematically co-produced and captured as a framework for planning nature-based solutions that emerged during the Connecting Nature project. The Connecting Nature Framework is a three-stage, iterative process that involves seven key activity areas for mainstreaming nature-based solutions: technical solutions, governance, financing and business models, nature-based enterprises, co-production, reflexive monitoring, and impact assessment. The tested and applied framework is designed to address and overcome barriers to the implementation of nature-based solutions in cities via a co-created, iterative, and reflective approach. The planning process guided by the proposed framework has already yielded promising results with some of the cities of the project, though further usage and its adoption by other cities is needed to explore its potential in different contexts especially in the Global South. The paper concludes with suggestions on how this may be realised

On the power of the conditional likelihood ratio and related tests for weak-instrument robust inference

Power curves of the Conditional Likelihood Ratio (CLR) and related tests for testing H0:β = β0 in linear models with a single endogenous variable, y = xβ+u, estimated using potentially weak instrumental variables have been presented for two different designs. One design keeps the variance matrix of the structural and first-stage errors, Σ, constant, the other instead keeps the variance matrix of the reduced-form and first-stage errors, Ω, constant. The values of Σ govern the endogeneity features of the model. The fixed-Ω design changes these endogeneity features with changing values of β in a way that makes it less suitable for an analysis of the behaviour of the tests in low to moderate endogeneity settings, or when β and the correlation of the structural and first-stage errors, ρuv, have the same sign. At larger values of |β|, the fixed-Ω design implicitly selects values for Σ where the power of the CLR test is high. We further show that the Likelihood Ratio statistic is identical to the t0(βb L) 2 statistic as proposed by Mills et al. (2014), where βb L is the Liml estimator. In fixedΣ design Monte Carlo simulations, we find that Liml- and Fuller-based conditional Wald tests and the Fuller-based conditional t 2 0 test are more powerful than the CLR test when the degree of endogeneity is low to moderate. The conditional Wald tests are further the most powerful of these tests when β and ρuv have the same sign. We show that in the fixed-Ω design, setting β0 = 0 and the diagonal elements of Ω equal to 1 is not without loss of generality, unlike in the fixed-Σ design

On the power of the conditional likelihood ratio and related tests for weak-instrument robust inference

Power curves of the Conditional Likelihood Ratio (CLR) and related tests for testing H0:β = β0 in linear models with a single endogenous variable, y = xβ+u, estimated using potentially weak instrumental variables have been presented for two different designs. One design keeps the variance matrix of the structural and first-stage errors, Σ, constant, the other instead keeps the variance matrix of the reduced-form and first-stage errors, Ω, constant. The values of Σ govern the endogeneity features of the model. The fixed-Ω design changes these endogeneity features with changing values of β in a way that makes it less suitable for an analysis of the behaviour of the tests in low to moderate endogeneity settings, or when β and the correlation of the structural and first-stage errors, ρuv, have the same sign. At larger values of |β|, the fixed-Ω design implicitly selects values for Σ where the power of the CLR test is high. We show that the Likelihood Ratio statistic is identical to the t0(βb L) 2 statistic as proposed by Mills, Moreira, and Vilela (2014), where βb L is the LIML estimator. In fixed-Σ design Monte Carlo simulations, we find that LIMLand Fuller-based conditional Wald tests and the Fuller-based conditional t 20 test are more powerful than the CLR test when the degree of endogeneity is low to moderate. The conditional Wald tests are further the most powerful of these tests when β and ρuv have the same sign. We show that in the fixed-Ω design, setting β0 = 0 and the diagonal elements of Ω equal to 1 is not without loss of generality, unlike in the fixed-Σ design