Explore the vast range of titles available.

This paper highlights several areas where graphical techniques can be harnessed to address the problem of measurement errors in causal inference. In particular, it discusses the control of unmeasured confounders in parametric and nonparametric models and the computational problem of obtaining bias-free effect estimates in such models. We derive new conditions under which causal effects can be restored by observing proxy variables of unmeasured confounders with/without external studies.

We prove that local projections (LPs) and Vector Autoregressions (VARs) estimate the same impulse responses. This nonparametric result only requires unrestricted lag structures. We discuss several implications: (i) LP and VAR estimators are not conceptually separate procedures; instead, they are simply two dimension reduction techniques with common estimand but different finite-sample properties. (ii) VAR-based structural identification—including short-run, long-run, or sign restrictions—can equivalently be performed using LPs, and vice versa. (iii) Structural estimation with an instrument (proxy) can be carried out by ordering the instrument first in a recursive VAR, even under noninvertibility. (iv) Linear VARs are as robust to nonlinearities as linear LPs.

Economic theory assigns a central role to risk preferences. This article develops a measure of relative risk tolerance using responses to hypothetical income gambles in the Health and Retirement Study. In contrast to most survey measures that produce an ordinal metric, this article shows how to construct a cardinal proxy for the risk tolerance of each survey respondent. The article also shows how to account for measurement error in estimating this proxy and how to obtain consistent regression estimates despite the measurement error. The risk tolerance proxy is shown to explain differences in asset allocation across households.

Information Systems (ISs) research frequently relies on digital trace data, often using simple activity counts as proxies for complex latent constructs like ‘experience’. However, the validity of such proxies is often assumed rather than critically scrutinized. This study problematizes this practice by treating a common proxy—a creator’s prior project count on Kickstarter—not as a measure of experience, but as a focal signal whose meaning is inherently ambiguous and context-dependent. By analyzing large-scale data (N ≈ 16,407 projects), we uncover a nuanced ‘experience paradox.’ The proxy exhibits a significant inverted-U association with backer mobilization and non-linearly moderates the value of other positive signals. Strikingly, it also maintains a persistent negative direct association with total funding, with its meaning varying significantly across project categories. These findings reveal the profound ambiguity of seemingly objective digital traces. Our primary contribution is methodological and theoretical: we provide a robust empirical critique of naive proxy use and refine signaling theory for digital contexts by integrating it with cognitive limitations and contextual factors. We urge IS scholars to develop more sophisticated measurement models and offer specific, evidence-based cautions for platform managers against the simplistic use of activity metrics in the digital economy.

We consider identification and estimation of the firm-level gross production function with a controlled productivity evolution process and endogenous contemporaneous productivity determinants in the absence of instrumental variables (IVs). We allow the joint determination of firm productivity and its determinants, such as research and development, exports, and foreign direct investment, which is motivated by the recognition that certain unobserved confounders, such as CEO ability and managerial strategies, may simultaneously affect both productivity and these determinants. This assumption is in sharp contrast to those used in previous studies on proxy-variable estimation of production functions, in which productivity processes without determinants or with exogenous/predetermined determinants are often assumed. Since IVs for endogenous productivity determinants are in general difficult to obtain in the production context, we propose an IV-free generalized method of moments (GMM) estimator based on Lewbel et al. (2023) and use higher-order moments for unobserved errors in addition to conventional orthogonality conditions. We demonstrate the finite sample performance of the proposed estimator through Monte Carlo simulations. We also apply the methodology to investigate the impact of foreign equity on the productivity of Chinese manufacturing firms.

In contrast to a large body of scientific literature that is based on empirical data and physically based and mathematical analyses, Wolfe et al. (2020) cited proxy-based paleolimnological evidence and argued that the regulation of Peace River has not played a role in the reduced incidence of large ice-jam floods. Such events are essential to the sustenance of perched basins located in the Peace Sector of the Peace–Athabasca Delta. Herein, the arguments advanced by Wolfe et al. (2020) are critically examined and shown to be unconvincing. Relevant literature indicates that a drying trend was first noticed after construction of the Bennett Dam. It is shown, moreover, that the belatedly questioned Traditional Knowledge and Historical ice-jam flood record is a reliable source of information, at least with respect to large floods, which are crucial to perched-basin replenishment. Detailed examination of the Wolfe et al. (2020) magnetic susceptibility (MS) profiles and their interpretation points to serious inconsistencies and leads to a renewed recommendation for coring perched, rather than readily flooded, basins in the future. It is also recommended that the oxbow lakes cored nearly two decades ago be revisited to obtain updated MS profiles. Deficiencies in the interpretation of inferred isotopic-composition time series of three perched basins suggest that all factors influencing such environmental variables be considered before drawing conclusions regarding the frequency of past floods. Contrairement a une litterature scientifique abondante qui repose sur des donnees empiriques et des analyses physiques et mathematiques, Wolfe et coll. (2020) citent des preuves paleolimnologiques basees sur des donnees indirectes et soutiennent que la regulation de la riviere de la Paix n’a pas joue de role dans la reduction de l’incidence des grandes inondations dues aux embacles. De tels evenements sont essentiels a la subsistance des bassins perches situes dans le secteur de la Paix du delta Paix-Athabasca. Les arguments avances par Wolfe et coll. (2020) sont ici examines de maniere critique et s’averent peu convaincants. La litterature pertinente indique qu’une tendance a l’assechement a ete remarquee pour la premiere fois apres la construction du barrage de Bennett. Il est en outre demontre que le savoir traditionnel, interroge tardivement, et le registre historique des inondations dues aux embacles constituent des sources d’information fiables, du moins en ce qui concerne les grandes inondations, qui sont cruciales pour la reconstitution des bassins perches. L’examen detaille des profils de susceptibilite magnetique (SM) de Wolfe et coll. (2020) et leur interpretation fait apparaitre de graves incoherences et conduit a recommander a nouveau a l’avenir le carottage des bassins perches plutot que des bassins facilement inondables. Il est egalement recommande de reexaminer les lacs en croissant carottes il y a pres de deux decennies afin d’obtenir des profils de SM actualises. Les lacunes dans l’interpretation des series chronologiques de la composition isotopique deduite de trois bassins perches suggerent que tous les facteurs influencant ces variables environnementales doivent etre pris en compte avant de tirer des conclusions concernant la frequence des inondations passees.

In this paper, we focus on estimating output growth and its components attributed to quasi-fixed inputs, variable inputs, and productivity change, while treating variable inputs as endogenous. We consider two approaches. In the classical approach the time trend variable proxies for technical (productivity) change, while in the productivity (proxy variable) approach, we add a “productivity” term which is correlated with the variable inputs. Therefore, estimation strategies in the two models are different. Instead of using a Cobb–Douglas production function, we employ a translog production function to add flexibility. We showcase our theoretical results with Chinese manufacturing as an empirical exercise.

Significant ecosystem changes in the Gulf of St. Lawrence (GSL), Canada, have had far-reaching effects at all trophic levels. The abundance of fin whales Balaenoptera physalus has declined significantly in the northern GSL over the past decade. This study aimed to test the hypothesis that the observed decline was correlated to changing environmental conditions. Cetacean sightings data from 292 surveys, resulting in 2986 fin whale encounters from 2007 to 2013, were used to fit 2 separate generalised additive models in terms of (1) bathymetric and oceanographic variables (the proxy model) and (2) modelled krill biomass (the prey model). The concept of ‘handling time’ was introduced to correct for time off search effort, applicable to other studies relying on opportunistically sampled data. While a positive correlation between krill biomass and fin whale numbers was found, the performance of the proxy model (24.2% deviance explained) was overall better than the prey model (11.8%). Annual predictive maps derived from the final proxy model highlighted 2 key areas with recurrently high relative fin whale abundance and a significant overlap with shipping lanes. While both models provided evidence for an annual decline in relative fin whale abundance, static bathymetric features were the most important predictors of habitat use, and no correlation between dynamic variables and the decline was found. High resolution prey data and a better understanding of the feeding ecology of fin whales are proposed to further investigate the predator–prey relationship and decline of fin whales in the GSL.

In this study, we leverage geographical coordinates and firm-level panel data to uncover variations in production across different locations. Our approach involves using a semiparametric proxy variable regression estimator, which allows us to define and estimate a customized production function for each firm and its corresponding location. By employing kernel methods, we estimate the nonparametric functions that determine the model’s parameters based on latitude and longitude. Furthermore, our model incorporates productivity components that consider various factors that influence production. Unlike spatially autoregressive-type production functions that assume a uniform technology across all locations, our approach estimates technology and productivity at both the firm and location levels, taking into account their specific characteristics. To handle endogenous regressors, we incorporate a proxy variable identification technique, distinguishing our method from geographically weighted semiparametric regressions. To investigate the heterogeneity in production technology and productivity among Norwegian grain farmers, we apply our model to a sample of farms using panel data spanning from 2001 to 2020. Through this analysis, we provide empirical evidence of regional variations in both technology and productivity among Norwegian grain farmers. Finally, we discuss the suitability of our approach for addressing the heterogeneity in this industry.

Of the readily computed proxies for the prevalence of gun ownership, one, the percentage of suicides committed with a gun, is most highly correlated with survey-based estimates. It is the best choice for use in cross-section analysis of the effect of gun prevalence on crime patterns across states and larger counties. Analysis of this proxy measure for the period 1979–1997 demonstrates that the geographic structure of gun ownership has been highly stable. That structure is closely linked to rural tradition. There is, however, some tendency toward homogenization over this period, with high-prevalence states trending down and low-prevalence states trending up.