Search results for " Bias"

Do-search -- a tool for causal inference and study design with multiple data sources

2020

Epidemiologic evidence is based on multiple data sources including clinical trials, cohort studies, surveys, registries, and expert opinions. Merging information from different sources opens up new possibilities for the estimation of causal effects. We show how causal effects can be identified and estimated by combining experiments and observations in real and realistic scenarios. As a new tool, we present do-search, a recently developed algorithmic approach that can determine the identifiability of a causal effect. The approach is based on do-calculus, and it can utilize data with nontrivial missing data and selection bias mechanisms. When the effect is identifiable, do-search outputs an i…

Structural bias in population-based algorithms

2014

Abstract Challenging optimisation problems are abundant in all areas of science and industry. Since the 1950s, scientists have responded to this by developing ever-diversifying families of ‘black box’ optimisation algorithms. The latter are designed to be able to address any optimisation problem, requiring only that the quality of any candidate solution can be calculated via a ‘fitness function’ specific to the problem. For such algorithms to be successful, at least three properties are required: (i) an effective informed sampling strategy, that guides the generation of new candidates on the basis of the fitnesses and locations of previously visited candidates; (ii) mechanisms to ensure eff…

Causal Effect Identification from Multiple Incomplete Data Sources: A General Search-Based Approach

2021

Causal effect identification considers whether an interventional probability distribution can be uniquely determined without parametric assumptions from measured source distributions and structural knowledge on the generating system. While complete graphical criteria and procedures exist for many identification problems, there are still challenging but important extensions that have not been considered in the literature. To tackle these new settings, we present a search algorithm directly over the rules of do-calculus. Due to generality of do-calculus, the search is capable of taking more advanced data-generating mechanisms into account along with an arbitrary type of both observational and…

Conditional Bias Robust Estimation of the Total of Curve Data by Sampling in a Finite Population: An Illustration on Electricity Load Curves

2020

Abstract For marketing or power grid management purposes, many studies based on the analysis of total electricity consumption curves of groups of customers are now carried out by electricity companies. Aggregated totals or mean load curves are estimated using individual curves measured at fine time grid and collected according to some sampling design. Due to the skewness of the distribution of electricity consumptions, these samples often contain outlying curves which may have an important impact on the usual estimation procedures. We introduce several robust estimators of the total consumption curve which are not sensitive to such outlying curves. These estimators are based on the conditio…

2015

Recent evidence suggests a rather gradual developmental trajectory for processing vertical relational face information, lasting well into late adolescence (de Heering and Schlitz, 2012). Results from another recent study (Tanaka et al., 2014) indicate that children and young adolescents use a smaller spatial integration field for faces than do adults, which particularly affects assessment of long-range vertical relations. Here we studied sensitivity to replacement of eyes and eyebrows (F), variation of inter-eye distance (H) and eye height (V) in young adolescents (11-12 years), young (21-25 years) and middle-age adults (51-62 years). In order to provide a baseline for potential age effects…

The Psychological Foundations of Management in Family Firms: Values, Biases, and Heuristics

2021

Considering the heterogeneity of family firm behaviors as reflecting the values, biases, and heuristics of individuals, we discuss the implications of the psychological foundations of management in family firms. We develop a conceptual framework for investigating how the values, biases, and heuristics of family and nonfamily members affect strategic decision-making and the outcomes of family firms. To advance the field, we put forward some relevant questions and offer a future research agenda at the intersection of the psychological foundations of management and family business.

Testing-the-Waters Policy With Hypothetical Investment: Evidence From Equity Crowdfunding

2020

International audience; Digitization has enabled “testing-the-waters” in entrepreneurial finance whereby investors can make nonbinding commitments in equity crowdfunding prior to an actual campaign to ascertain interest in the project. We consider whether these nonbinding equity investment commitments are informative about actual investments during the campaign and, thus, ultimate startup funding success. The data indicate that only 18% of nonbinding commitments are, in fact, invested. The evidence is consistent with hypothetical bias. Hypothetical bias is significantly less pronounced among women and among investors living in higher income areas or in areas with higher levels of education.…

The interaction effect of gender and ethnicity in loan approval: A Bayesian estimation with data from a laboratory field experiment

2019

Microfinance targets women and uses loan provision as a tool for empowerment, which translates into better household nutrition, improved education, and a scale down of domestic violence. However, ethnic discrimination in microfinance may exist in countries with a segregated indigenous population. We assessed this possibility with a field experiment in Bolivia. The controlled laboratory experiment evaluated whether credit officers rejected microloan applications based on the interaction effect of ethnicity and gender of potential borrowers. Point estimates of a Bayesian mixed‐effects logistic regression, estimated with the experimental data, indicate that nonindigenous women have double the …

The Bias toward the Right Side of Others Is Stronger for Hands than for Feet

2021

As shown by a series of previous studies, ambiguous human bodies performing unimanual or unipedal actions tend to be perceived more frequently as right-handed or right-footed rather than left-handed or left-footed, which indicates a perceptual and attentional bias toward the right side of others&rsquo

El sesgo mediocéntrico del "framing" en España: una revisión crítica de la aplicación de la teoría del encuadre en los estudios de comunicación

2016

Artikulu honetan kritikoki aztertuko dira Espainian framing-ari buruzko literaturan gailentzen diren ikuspegi teoriko eta metodologikoak. Azterketaren helburua da azpimarratzea bitartekoa erdigune duen joera bat dagoela; izan ere, ikasketetan aldagai independente gisa landu ohi dira kazetaritza-enkoadraketak, baina ez dira horiek ekoiztean eta negoziatzean dagoen dinamika-eta gatazka-prozesua jorratzen. Joera horren arrazoia da markoak kazetaritza-errutinen emaitza gisa hartzen direla, eta, hori dela eta, ez da kontuan hartzen kazetaritza-marko horien ekoizpenen atzean hainbat eragin politiko, sozial eta ideologiko daudela.; This article provides a critical review of the theoretical and met…