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Life Cycle Assessment (LCA) is a foundational method for quantitative assessment of sustainability. Increasing data availability and rapid development of machine learning (ML) approaches offer new opportunities to advance LCA. Here, we review current progress and knowledge gaps in applying ML techniques to support LCA, and identify future research directions for LCAs to better harness the power of ML. This review analyzes forty studies reporting quantitative assessment with a combination of LCA and ML methods. We found that ML approaches have been used for generating life cycle inventories, computing characterization factors, estimating life cycle impacts, and supporting life cycle interpretation. Most of the reviewed studies employed a single ML method, with artificial neural networks (ANNs) as the most frequently applied approach. Both supervised and unsupervised ML techniques were used in LCA studies. For studies using supervised ML, training datasets were derived from diverse sources, such as literature, lab experiments, existing databases, and model simulations. Over 70 % of these reviewed studies trained ML models with less than 1500 sample datasets. Although these reviewed studies showed that ML approaches help improve prediction accuracy, pattern discovery and computational efficiency, multiple areas deserve further research. First, continuous data collection and compilation is needed to support more reliable ML and LCA modeling. Second, future studies should report sufficient details regarding the selection criteria for ML models and present model uncertainty analysis. Third, incorporating deep learning models into LCA holds promise to further improve life cycle inventory and impact assessment. Finally, the complexity of current environmental challenges calls for interdisciplinary collaborative research to achieve deep integration of ML into LCA to support sustainable development.

This series of four presentations sought to examine case studies of Greek-Russian relations in the early modern and, mostly, modern period. In the choice of topics, I was guided by two considerations: first, I sought to highlight topics that, to my mind, have not yet attracted the attention they deserve in historiography. For example, although alms collections in the Russian Empire in the early modern period have been discussed repeatedly, this has not been the case until quite recently for t...

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This paper examines the effect of market-entry timing on a firm’s speed and cost of entry in a setting where a firm needs to build a plant for market entry. Based on our developed analytical model, we provide seven scenarios of the market-entry timing effect on a firm’s entry speed and cost. We test hypotheses in the liquefied natural gas (LNG) industry. We use Wooldridge’s three-step instrumental variable (IV) approach to account for endogeneity bias. We find that a late entrant has (1) a shorter time-to-build and (2) a higher cost-to-build relative to an early entrant. Further, (3) the late entrant positively moderates the negative relationship of time-to-build and cost-to-build (i.e., the negative relationship of time-to build and cost-to-build becomes less negative for the late entrant). These empirical results are consistent with the prediction of when both revenue effect (i.e., revenue curve shift) and cost effect (i.e., cost curve leftward shift) exist.

Invisible Mothers: Unseen yet Hypervisible After Incarceration, the new book by Dr. Janet Garcia-Hallett, has almost innumerable contributions to the field. The first thing that the reader will likely notice that makes this work stand out is the impact of Garcia-Hallett’s positionality as an Afro-Latina mother on the holistic understanding of the experiences of the Black and brown women as mothers and victims of the racist American carceral system. Garcia-Hallett grew up in Harlem, witnessing the transformation of her community due to the takeover of the penal system. For this book, she interviewed 37 mothers in New York City with histories of incarceration, and her writing skilfully puts the reader in her shoes as she presents the findings from her interviews, which took place in their kitchens, booths in McDonald’s, and at tables in shelters. In her exploration of these women’s experiences, Garcia-Hallett departs from the traditional pitiful exploration of their lives, but instead, paints a complicated, multifaceted picture of women engaging actively in many different types of motherwork, while facing almost constant obstacles from racist and misogynist criminal legal and child welfare systems that criminalize, pathologize and penalize their survival of their marginalization, rather than helping ‘save’ children and their mothers. She provides a critical and structural analysis while also introducing each woman as deeply unique in her strengths and challenges and is able to acknowledge the importance of the children without letting them overshadow the mothers. This is no small feat.

Several predictions of sperm competition theory are not well supported empirically. One potential reason is that most current theory and empirical research ignore how the social environment influence the temporal dynamics of mating. We propose that understanding these dynamics is key to understanding sexual selection and improving the predictive power of theory. To demonstrate the importance of these dynamics, we quantify how males’ social role, interactions among males, and current social environment influence the timing of mating in Symphodus ocellatus, a species with three alternative male reproductive tactics. Nesting males spawn synchronously with females; sneakers and satellites sneak-spawn with some time delay. Satellites also cooperate with nesting males. We found that satellites have shorter sneak-spawning delays than sneakers, a benefit of their cooperation with nesting males. Sneak-spawning delays decreased with increasing nest activity for sneakers but not for satellites, suggesting that sneakers may benefit from increased sperm competition intensity. Current sperm competition models ignore this potential benefit, which may be why the prediction that males should decrease investment when sperm competition involves more than two males is not well supported. Our study provides insight into mechanisms that drive variation in the timing of spawning, which could explain mismatches between theoretical and empirical results.

Firm speed has long been a construct of interest among managers and researchers. Despite its importance, making a ceteris paribus comparison of speed can be challenging. In the current paper, we suggest an alternative to the conventional way of capturing the speed ceteris paribus. First, we illustrate the concept of faster speed in strategic management research. Second, we use numerical simulation data to illustrate the challenges of the conventional methodology, known as the nonlinear transformation of variables. We show that this method is difficult to apply and may produce an inaccurate measurement of the concept unless the exact functional form is chosen. Third, we suggest an alternative methodology, known as data envelopment analysis. This accounts for the challenges of the conventional methodology when we do not know the accurate functional form for nonlinear transformation, while performing as well as the best of the conventional approach. Finally, by using actual firm data, we show that our suggested methodology can be an effective alternative to the conventional approach of capturing a firm’s speed.

Conventional wisdom suggests that an increase in a firm’s operational effectiveness will increase its economic performance. However, we show that an increase in a firm’s operational effectiveness can decrease its economic performance. Specifically, a firm’s increase in operational effectiveness of its existing projects following a positive demand shock can limit its profitable growth as its strategic resources are not allocated to pursuing new projects, thereby incurring opportunity costs that can lower its economic performance. We corroborate this reasoning in the context of the liquefied natural gas industry, which experienced a positive demand shock in 2000 due to energy market liberalization. We find empirically that a firm’s operational effectiveness increases its Tobin’s Q in the pre-shock period and reduces it in the post-shock period.

Managers often need to stay motivated and effectively motivate others. Therefore, they should rely on evidence-based interventions to manage the daily routine of motivational dynamics at work. This research answered how self-determination-theory-based interventions change employees’ motivation and motivational consequences during short time frames (i.e., within an hour, within a few weeks/months). Field study one focused on assessing the effectiveness of a one-day training workshop in helping improve managers’ work motivation, basic psychological needs satisfaction/frustration, and changing managers’ needs-supportive/thwarting behaviors within a few weeks. Results supported the training effectiveness as managers were rated less needs-thwarting by their direct subordinates and self-reported improvement in needs satisfaction/frustration six weeks after completing the training program. Online study two used the mean and covariance structure analysis and tested the three types of basic psychological needs supportive/thwarting and control conditions (3x2x1 factorial design) on the situational motivation, vitality, and general self-efficacy for playing online word games within 30 minutes. Multi-group confirmatory factor analysis (CFA) confirmed the scalar measurement invariance, then latent group means comparison results showed consistently lower controlled motivation across the needs-supportive and thwarting experimental conditions. During a quick online working scenario, the theory-based momentary intervention effectively changed situational extrinsic self-regulation in Amazon MTurk participants. Supplementary structural equation modeling (SEM) analyses using experience samples supported the indirect dual-path model from basic needs satisfaction to vitality and general efficacy via situational motivation. We discussed the theoretical implications of the temporal properties of work motivation, the practical implications on employee training and organizational change programs, and the limitations.

The grand challenge of preparing for climate impacts through climate adaptation relies on intermediaries, including local NGOs, consulting firms, and government agencies. Climate adaptation elicits evaluative tensions coming from what we call the dual organizational complexity. The dual organizational complexity includes evaluation ambiguity in (1) the interconnectedness and co-evolutionary dynamics of locally bounded social and ecological systems and (2) an increasingly complex network of interconnected organizations, including a diverse set of public, private, and semi-private actors who provide funding, market power, and expertise. We find that intermediaries address evaluative tensions through organizational scaffolding or building socio-material infrastructures that can support resilience and increase evaluative and adaptive capacity for future projects, albeit imperfectly. Importantly, we argue that climate adaptation needs facilitators with the capacity to connect very localized bottom-up needs to top-down resources in a continuous cycle of resource allocation, communication, and accountability, especially in the face of the increasing organizational complexity involved.