Alternative Causal Mechanisms Research Articles

Does variety in hedonic spending improve happiness? Testing alternative causal mechanisms between hedonic variety and subjective well-being

Previous research has found only a small, inconsistent association between hedonic consumption and subjective well-being, often attributed to individuals adapting to the happiness gains from their purchases. Given that diverse experiences can reduce or avert hedonic adaptation, we hypothesized that variety in hedonic spending would be associated with greater well-being. This hypothesis was tested in four studies (total N = 2,920), using both self-reported and objective bank-reported spending data. In our correlational analyses, hedonic spending variety was uniquely associated with well-being, even after controlling for total hedonic spending and other financial variables. Our investigation also explored the directional relationship between hedonic spending variety and well-being, yielding mixed results for both causal pathways in two time-lagged panel studies. Additionally, in two parallel experiments, participants reported that varied hedonic spending contributed more to happiness than uniform hedonic spending. These findings have implications for basic well-being science by testing how varied consumption behaviors and well-being are interrelated.

Causal mediation analysis in presence of multiple mediators uncausally related.

Mediation analysis aims at disentangling the effects of a treatment on an outcome through alternative causal mechanisms and has become a popular practice in biomedical and social science applications. The causal framework based on counterfactuals is currently the standard approach to mediation, with important methodological advances introduced in the literature in the last decade, especially for simple mediation, that is with one mediator at the time. Among a variety of alternative approaches, Imai et al. showed theoretical results and developed an R package to deal with simple mediation as well as with multiple mediation involving multiple mediators conditionally independent given the treatment and baseline covariates. This approach does not allow to consider the often encountered situation in which an unobserved common cause induces a spurious correlation between the mediators. In this context, which we refer to as mediation with uncausally related mediators, we show that, under appropriate hypothesis, the natural direct and joint indirect effects are non-parametrically identifiable. Moreover, we adopt the quasi-Bayesian algorithm developed by Imai et al. and propose a procedure based on the simulation of counterfactual distributions to estimate not only the direct and joint indirect effects but also the indirect effects through individual mediators. We study the properties of the proposed estimators through simulations. As an illustration, we apply our method on a real data set from a large cohort to assess the effect of hormone replacement treatment on breast cancer risk through three mediators, namely dense mammographic area, nondense area and body mass index.

Causation, levels of analysis and explanation in systems ergonomics – A Closer Look at the UK NHS Morecambe Bay investigation

This paper extends an earlier examination of the concept of ‘mesoergonomics’ (Karsh et al., 2014) and its application to Human Factors/Ergonomics (HFE). Karsh et al. (2014) developed a framework for mesoergonomic inquiry based on a set of steps and questions, the purpose of which was to encourage researchers to cross system levels in the studies (e.g., organisation-group-individual levels of analysis) and to explore alternative causal mechanisms and relationships within their data. The present paper further develops the framework and draws on previous work across a diverse range of sources (safety science, systems theory, the sociology of disaster and ethology) which has examined the subject of accident causation, levels of analysis and explanatory factors contributing to system failure. The outcomes from this exercise are a revised framework which seeks to explore what we term ‘isomorphisms’ and includes questions covering: (a) how internal isomorphisms develop or evolve within the system; and, (b) how these isomorphisms are shaped by cultural, professional and other forms of external influence. The workings of the revised framework are illustrated through using the example of the UK NHS Morecambe Bay Investigation (Kirkup, 2015). The paper concludes with a summary of ways forward for the framework, as well as new directions for theory within systems ergonomics/human factors.

Unravelling the relationships between life history, behaviour and condition under the pace-of-life syndromes hypothesis using long-term data from a wild bird

The hypothesis of pace-of-life syndromes (POLS) predicts relationships between traits including life history traits and risk-taking behaviour that can be mediated by the trade-off between current and future reproductive value. However, alternative causal mechanisms may also generate covariance among these traits without trade-offs. We investigated the relationships between survival to the next year, current reproductive investment and risk-taking behaviour (flight initiation distance) in male collared flycatchers, Ficedula albicollis, using long-term data. We used structural equation modelling (SEM) to uncover whether the associations among traits are mediated by a common latent factor that determines how individuals balance the trade-off between current and future reproductive value. As trade-offs could be concealed when there are differences in resource acquisition between individuals, we also included potential causes of these differences, body mass and body size, in the analysis. We found that risk-taking behaviour was positively related to reproductive investment and negatively to survival to the next year as could be predicted if investment into a risky behaviour is traded against future prospects. However, the most supported SEM model also suggested that survival to the next year was positively related to current reproductive investment, contrary to predictions of a hypothesis based on trade-off. These results remained qualitatively similar when controlling for body condition. In conclusion, we only could derive partial support for the POLS hypothesis. We suggest that aspects of individual quality, and not only trade-offs, should also be considered when interpreting the relationships between life history and behavioural traits. We investigated the association between two life history components (survival to the next year and current reproductive effort) and risk-taking behaviour, relying on long-term records from a passerine bird, to investigate the predictions of the pace-of-life syndrome (POLS) hypothesis. Using structural equation modelling, we found support for a causal model that implies that risk-taking negatively affects survival to the next year and that survival to the next year and current reproductive effort are strongly and positively associated. Controlling for the effect of body condition did not fundamentally change these relationships. We could not find conclusive evidence for the investigated traits being mediated by a common underlying factor, as generally predicted by the POLS hypothesis. However, the sign of the relationship between risk-taking behaviour and survival to the next year was as predicted by the POLS hypothesis.

Idiopathic Environmental Intolerance: A Comprehensive Model

Idiopathic environmental intolerance refers to a group of poorly understood health conditions characterized by heterogeneous somatic symptoms that occur in response to environmental triggers, but for which no physiological causes can be found. We focus on three varieties, namely symptoms attributed to (a) chemical substances, (b) electromagnetic fields, and (c) infrasound and vibroacoustic sources. As no clear link with organ pathology or dysfunction has been established so far, we review critical evidence about alternative causal mechanisms as a platform for a novel unifying model of these conditions. There is consistent evidence that expectancy and nocebo mechanisms are critically involved. Using recent predictive coding models of brain functioning, we describe a comprehensive new model to explain how symptoms come about and become linked to specific environmental cues. This new model integrates phenomenally different pathologies, suggests testable new hypotheses, and specifies implications for treatment.

'Big Data' on the Big Screen: Revealing Latent Similarity among Movies and Its Effect on Box Office Performance

In the movie industry context, this paper seeks to determine whether the number of categories a product belongs to is an explanatory factor of performance. The prevailing, but unproven hypothesis in current research is that spanning multiple categories is associated with worse performance. The intuition is that consumers are more likely to ignore products that do not have a clear fit with existing market positions. However, no studies have provided evidence for the causality of the correlation between category-spanning and performance. Importantly, there exist at least two major reasonable alternative causal mechanisms that could account for the relationship, which prevents us from interpreting the relationship as causal. Moreover, current research views the way consumers categorize products as largely unobservable. Instead, for tractability, it relies on category labels assigned to products by market intermediaries as a proxy for how consumers would categorize products. Recent studies have questioned whether this approach truly reflects the way individual consumers categorize. This paper seeks to shed light on previously unobservable consumer categorization through visible online consumer demand patterns, and address the question of which measure of category-spanning is better able to explain performance: a traditional movie’s genre count, or a new measure based on consumer rental patterns? The widespread digitization of consumer data, enabled by recent technological changes, offers an opportunity to observe consumer movie preferences through their online movie rental behavior. From these data, we can get closer to capturing the way consumers categorize movies. Specifically, I use Amazon Instant Video’s “Customers who rent this [focal movie] also rented... co-rental lists to uncover latent relationships between movies from revealed rental patterns. Then, I construct a measure of category-spanning, called Latent Similarity, to quantify a movie’s similarity to other movies based on their shared co-rentals. My empirical approach seeks to provide supportive evidence that category-spanning, as measured by Latent Similarity, is an explanatory factor of performance, as measured by box office revenues. In this context, it is difficult to show causality directly. This would entail changing a product’s categories while leaving all its other characteristics the same. Instead, I attempt to provide indirect evidence that category-spanning affects performance by refuting two of the most plausible alternative causal mechanisms (reverse causality, and unobservable quality as a common cause). I also show that as a measure of category-spanning, Latent Similarity is more explanatory of performance than the traditional movie genre count. Methodologically, the paper employs a combination of rigorous econometric methods, including instrumental variable and control function approaches, to provide support for the causality of the relationship between category-spanning and performance.

Does Training Matter? Evidence from Performance Management Reforms

AbstractTraining is much discussed but rarely studied in public management. Using multiple waves of survey data, the authors examine the effects of training on the implementation of performance management reforms in the U.S. federal government, asking whether those exposed to training are more likely to use performance data and strategic goals when making decisions. Training is positively associated with reform implementation, but there is little evidence that this association can be explained by the development of specific capacities to overcome performance management challenges. The findings offer two implications for the practice and study of training. The authors propose that training is likely to succeed if it is designed and funded to close specific capacity gaps needed for successful reform implementation. However, it is also necessary to better understand alternative causal mechanisms by which training facilitates reform implementation, such as explaining and justifying reforms.Practitioner Points Training can facilitate the implementation of new policies by providing information about the policies, justifying why they are needed, and giving employees the capacity to put the new policies in place. Using training to build specific employee capacities is more complex, resource intensive, and rare than using training to provide information and justify reforms. Effective training in government requires not just more resources but also better understanding of the specific capacities needed and how to create them—research can help by identifying the most significant capacity gaps in policy implementation.

Foreign Aid as a Signal to Investors

Does development aid attract foreign direct investment (FDI) in post-conflict countries? This article contributes to the growing literature on effects of aid and on determinants of FDI by explaining how development aid in low-information environments is a signal that can attract investment. Before investing abroad, firms seek data on potential host countries. In post-conflict countries, reliable information is poor, in part because governments face unusual incentives to misrepresent information. In these conditions, firms look to signals. One is development aid, because donors tend to give more to countries they trust to properly handle the funds. Our results show that aid seems to draw FDI—however, this is conditional on whether the aid can be considered geostrategically motivated. We also show that this effect decreases as time elapses after the conflict. This suggests that aid’s signaling effect is specific to low-information environments, and helps rule out alternative causal mechanisms linking aid and FDI.

Identification and Sensitivity Analysis for Multiple Causal Mechanisms: Revisiting Evidence from Framing Experiments

Social scientists are often interested in testing multiple causal mechanisms through which a treatment affects outcomes. A predominant approach has been to use linear structural equation models and examine the statistical significance of the corresponding path coefficients. However, this approach implicitly assumes that the multiple mechanisms are causally independent of one another. In this article, we consider a set of alternative assumptions that are sufficient to identify the average causal mediation effects when multiple, causally related mediators exist. We develop a new sensitivity analysis for examining the robustness of empirical findings to the potential violation of a key identification assumption. We apply the proposed methods to three political psychology experiments, which examine alternative causal pathways between media framing and public opinion. Our analysis reveals that the validity of original conclusions is highly reliant on the assumed independence of alternative causal mechanisms, highlighting the importance of proposed sensitivity analysis. All of the proposed methods can be implemented via an open source R package,mediation.

Identification, Inference and Sensitivity Analysis for Causal Mediation Effects

Causal mediation analysis is routinely conducted by applied researchers in a variety of disciplines. The goal of such an analysis is to investigate alternative causal mechanisms by examining the roles of intermediate variables that lie in the causal paths between the treatment and outcome variables. In this paper we first prove that under a particular version of sequential ignorability assumption, the average causal mediation effect (ACME) is nonparametrically identified. We compare our identification assumption with those proposed in the literature. Some practical implications of our identification result are also discussed. In particular, the popular estimator based on the linear structural equation model (LSEM) can be interpreted as an ACME estimator once additional parametric assumptions are made. We show that these assumptions can easily be relaxed within and outside of the LSEM framework and propose simple nonparametric estimation strategies. Second, and perhaps most importantly, we propose a new sensitivity analysis that can be easily implemented by applied researchers within the LSEM framework. Like the existing identifying assumptions, the proposed sequential ignorability assumption may be too strong in many applied settings. Thus, sensitivity analysis is essential in order to examine the robustness of empirical findings to the possible existence of an unmeasured confounder. Finally, we apply the proposed methods to a randomized experiment from political psychology. We also make easy-to-use software available to implement the proposed methods.

Origin of the Newberry Hotspot Track: Evidence from shear-wave splitting

Located in the northwestern United States, the Newberry Hotspot Track consists of a sequence of age-progressive silicic volcanic domes and lava flows, showing a monotonic age progression from east to west ending at the Newberry Caldera. While mantle plumes are often called upon to explain hotspot tracks, the Newberry track cannot be the direct product of plate motion over a stationary mantle source as its orientation is ∼120° to plate motion, making it a good case study for alternative causal mechanisms of hotspot tracks. Four end-member tectonic models have been proposed: (1) subduction counterflow, (2) gravitational flow along the base of the lithosphere, (3) lithospheric faulting, and (4) extension of the Basin and Range. To get fabric information about the asthenosphere and constrain the possible flow fields beneath the Newberry track, SKS splitting measurements were made for 27 events at 12 stations of the Oregon Array for Teleseismic Study (OATS) along the track. A gradual rotation of the fast direction is observed from ENE–WSW at the northwest end of the array to E–W to the southeast and the delay times average 1.65 s. We infer that the SKS splits are the product of anisotropy in the asthenosphere and the anisotropy orientation does not vary with depth beneath the track. The average fast directions ENE–WSW to the northwest are consistent with generation by mantle shear parallel to the subduction of the Juan de Fuca Plate, and the more E–W fast directions to the east are perhaps due to shear caused by the Basin and Range extension. Since the observed fast directions are not parallel to the Newberry track, as the subduction counterflow model or the gravitational flow model suggests, the age-progressive volcanism is unlikely a direct product of asthenospheric flow. Instead, we propose that the Newberry track is the product of lithosphere-controlled processes.

Mid-Jurassic volcanic structures in the Outer Moray Firth Basin, UK

3D seismic mapping in the southern part of Quadrant 15 in the Outer Moray Firth Basin reveals an array of circular to oval downthrown blocks bound by steep ring faults. These lows affect Triassic and older strata, are approximately 1.5–2 km in diameter and 0.5–1 km deep. The footwall crests of the structures now lie at a depth of c. 2.5 km. Several alternative causal mechanisms for these circular fault blocks are examined including salt dissolution, strike-slip pull-apart and impact cratering, but in terms of geological and geometrical criteria, the most likely mechanism appears to be small calderas or diatreme-conduit collapse. Seismic data indicates that the circular structures cut Triassic, Permian and Devono-Carboniferous strata and are infilled with pre-Upper Oxfordian sediments, therefore they are broadly synchronous with Mid-Jurassic volcanism–local well control demonstrates the presence of several thousand feet of basalt tuffs and lavas. The model proposed here to account for the circular structures consists of an initial phase of diatreme/maar cratering as magmas associated with the Rattray Volcanics Member intruded shallow aquifers in the Pentland Formation fluviodeltaic rocks. These maars enlarged and deepened via conduit wall collapse, supplemented by downsag-faulting due to magma withdrawal. The post-volcanic evolution of the structures included (1) differential erosion creating accommodation space which may have been infilled with Oxfordian reservoir sands and (2) local reactivation by underlying basement faults in the Kimmeridgian.

Rapoport's rule: an explanation or a byproduct of the latitudinal gradient in species richness?

A recent explanation of the declining species richness gradient with increasing latitude away from the tropics implicated broad scale habitat variability, an associated range expansion, and a resulting increase in niche breadth. The niche breadth in turn was thought to affect richness by competition and rescue effect. While all three factors appear to be correlated, neither the postulated nor alternative causal mechanisms have been tested. We conduct such a test using a system which has all the attributes of the large scale pattern but which, in contrast to continental scale observations, allows for estimation or control of crucial variables such as taxonomic composition, habitat heterogeneity, habitat variability, exact species distribution, and local richness. Specifically, we test the alternative that the correlation between the geographical range of species and local diversity is a function of differential species survival and link this phenomenon to habitat variability. We use 40 species of aquatic invertebrates inhabiting a landscape of 49 miniature rock pools on the coast of Jamaica. The system we examined exhibits a gradient of increasing richness with decreasing habitat variability, analogous to the broad scale latitudinal pattern. Furthermore, species with broader ecological ranges are also broadly distributed. Superficially, this appears to be in agreement with the older explanations but two facts suggest different causes. First, there is no evidence of a ‘rescue effect’ maintaining high richness in many habitats despite their proximity to species sources. Second, ecologically broad species coexist with habitat specialists without reducing richness in jointly occupied habitats.