scholarly journals Understanding the Average Impact of Microcredit Expansions: A Bayesian Hierarchical Analysis of Seven Randomized Experiments

2019 ◽  
Vol 11 (1) ◽  
pp. 57-91 ◽  
Author(s):  
Rachael Meager
Keyword(s):  
External Validity ◽  
Hierarchical Models ◽  
Hierarchical Analysis ◽  
Randomized Experiments ◽  
Average Effect ◽  
Bayesian Hierarchical ◽  
Heterogeneous Effects ◽  
Average Impact ◽  
The Impact ◽  
Better Than

Despite evidence from multiple randomized evaluations of microcredit, questions about external validity have impeded consensus on the results. I jointly estimate the average effect and the heterogeneity in effects across seven studies using Bayesian hierarchical models. I  find the impact on household business and consumption variables is unlikely to be transformative and may be negligible. I find reasonable external validity: true heterogeneity in effects is moderate, and approximately 60 percent of observed heterogeneity is sampling variation. Households with previous business experience have larger but more heterogeneous effects. Economic features of microcredit interventions predict variation in effects better than studies’ evaluation protocols. (JEL D14, G21, I38, O12, O16, P34, P36)

scholarly journals Some do and some don’t? Accounting for variability of individual difference structures.

2017 ◽  
Author(s):  
Julia M. Haaf ◽  
Jeffrey Rouder
Keyword(s):  
Standard Deviation ◽  
Stroop Task ◽  
Hierarchical Models ◽  
Average Effect ◽  
Negative Effects ◽  
True Negative ◽  
Bayesian Hierarchical ◽  
Positive Effects ◽  
Negative Effect ◽  
Positive Effect

A prevailing notion in experimental psychology is that individuals' performance in a task varies gradually in a continuous fashion. In a Stroop task, for example, the true average effect may be 50ms with a standard deviation of say 30ms. In this case, some individuals will have greater effects than 50ms, some will have smaller, and some are fore-casted to have negative effects in sign - they respond faster to incongruent items than to congruent ones! But are there people who have a true negative effect in Stroop or any other task? We highlight three *qualitatively different* effects: negative effects, null effects, and positive effects. The main goal of this paper is to develop models that allow researchers to explore whether all three are present in a task: Do all individuals show a positive effect? Are there individuals with truly no effect? Are there any individuals with negative effects? We develop a family of Bayesian hierarchical models that capture a variety of these constraints. We apply this approach to Stroop interference experiments and a near-liminal priming experiment where the prime may be below and above threshold for different people. We show that most tasks people are quite alike - for example everyone has positive Stroop effects and nobody fails to Stroop or Stroops negatively. We also show a case that under very specific circumstances, we could entice some people to not Stroop at all.

scholarly journals Colonialism and Development in Africa

2017 ◽  
Author(s):  
Leander Heldring ◽  
James A. Robinson
Keyword(s):  
Colonial Period ◽  
Sub Saharan Africa ◽  
Average Effect ◽  
Heterogeneous Effects ◽  
The World ◽  
Negative Effect ◽  
Sub Saharan ◽  
The Impact

In this article, we evaluate the impact of colonialism on development in sub-Saharan Africa. In the world context, colonialism had very heterogeneous effects, operating through many mechanisms—sometimes encouraging development, sometimes retarding it. In the African case, however, this heterogeneity is muted, making an assessment of the average effect more interesting. To draw conclusions, it is necessary to know not just what actually happened to development during the colonial period but also what might have happened without colonialism and its legacy. In light of plausible counterfactuals, colonialism probably had a uniformly negative effect on development in Africa. To develop this claim, we distinguish between three sorts of colonies, each with a distinct performance within the cultural period, different counterfactuals, and varied legacies.

The impact of formality on firm profitability in Bolivia: an heterogeneous assessment

2012 ◽  
pp. 53-74
Author(s):  
Darwin Ugarte Ontiveros
Keyword(s):  
Empirical Literature ◽  
Large Firms ◽  
Marginal Effects ◽  
Heterogeneous Effects ◽  
Firm Profitability ◽  
The Impact ◽  
Formal Status

Recent evidence suggests that formality improves micro-firms profits in Bolivia. This gain is only for firms with 2 to 5 workers, while smaller and larger firms would lose out by formalizing (McKenzie and Sakho, 2010). However, as much of the empirical literature on this topic, the estimations are based on strong assumptions about unobservables. If the returns to formality vary among firms and these variations influence selection into formality, traditional estimators are biased (Heckman and Vytlacil, 2007). In this paper we considerthese elements to estimate the heterogeneous effects of formality on firm profits in Bolivia. We find remarkable heterogeneity in the returns to formality, from -3% to 6%. The group of firms with positive marginal effects from formality corresponds to those which are most likely to register. We also characterize the firms that likely benefit from having a formal status. These would correspond to large firms which work at big scales.

Bayesian Hierarchical Models to Augment the Mediterranean Forecast System

2008 ◽  
Author(s):  
Ralph F. Milliff ◽  
Mark Berliner ◽  
Emanuele D. Lorenzo ◽  
Christopher K. Wikle
Keyword(s):  
Hierarchical Models ◽  
Bayesian Hierarchical Models ◽  
Forecast System ◽  
Bayesian Hierarchical ◽  
The Mediterranean

Bayesian Hierarchical Models to Augment the Mediterranean Forecast System

2010 ◽  
Author(s):  
Christopher K. Wikle ◽  
L. M. Berliner ◽  
Emanuele Di Lorenzo ◽  
Ralph F. Milliff
Keyword(s):  
Hierarchical Models ◽  
Bayesian Hierarchical Models ◽  
Forecast System ◽  
Bayesian Hierarchical ◽  
The Mediterranean

Bayesian Hierarchical Models to Augment the Mediterranean Forecast System

2010 ◽  
Author(s):  
Ralph F. Milliff ◽  
Christopher K. Wikle ◽  
L. M. Berliner ◽  
Emanuele Di Lorenzo
Keyword(s):  
Hierarchical Models ◽  
Bayesian Hierarchical Models ◽  
Forecast System ◽  
Bayesian Hierarchical ◽  
The Mediterranean
Sign in / Sign up

Export Citation Format

Share Document