Are political activists driven by instrumental motives such as making a career in politics or mobilizing voters? We implement two natural field experiments in which party activists are randomly informed that canvassing is i) effective at mobilizing voters, or ii) effective for enhancing activists’ political careers. We find no effect of the treatments on activists’ intended and actual canvassing behaviour. The null finding holds despite a successful manipulation check and replication study, high statistical power, a natural field setting, and an unobtrusive measurement strategy. Using an expert survey, we show that the null finding shifted Bayesian posterior beliefs about the treatment’s effectiveness toward zero. The evidence thus casts doubt on two popular hypothesized instrumental drivers of political activism – voter persuasion and career concerns – and points toward expressive benefits as more plausible motives.

Along with increasing product complexity and quality requirements, the consistent consideration of inevitable production-induced variations within the product development process becomes a decisive factor for the market success of products. Consequently, various tolerancing approaches have emerged over the last few decades. However, tolerancing is considered complex in education, research, and industry, as it is a highly interdisciplinary task that takes place at different levels of detail, ranging from Robust Design to tolerance specification to manufacturing process design. This contribution proposes a novel approach that allows a holistic and structured description of tolerancing and fosters a common understanding among all involved stakeholders from design, manufacturing, and inspection. This is achieved by categorizing it into several distinct elements: activities, methods, tools, models and data, information, and knowledge. This ensures clarity and supports the utilization of existing approaches. While this contribution focuses on tolerancing in product design, the linkage to subsequent product realization stages and further engineering domains is also addressed in the proposed description scheme. An exemplary classification of research papers and a description of a practical development process of a technical system with its different tolerancing activities illustrate the benefits of the proposed description scheme.

Cyber-Physical-Systems provide extensive data gathering opportunities along the lifecycle, enabling data-driven design to improve the design process. However, its implementation faces challenges, particularly in the initial data capturing stage. To identify those, a comprehensive approach combining a systematic literature review and an industry survey was applied. Four groups of interrelated challenges were identified as most relevant to practitioners: data selection, data availability in systems, knowledge about data science processes and tools, and guiding users in targeted data capturing.

Digital transformation increases the need for interdisciplinary collaboration along the product lifecycle. It is currently hindered by a low data consistency resulting from the use of heterogeneous systems and data models. Especially in work planning, where several data models are combined, this decreases efficiency. Systems Lifecycle management (SysLM) offers a solution to this remedy. However, a sudden switch to SysLM is not possible in brownfields. Thus, it is necessary to examine the challenges and opportunities to derive case-specific measures that enable its adoption in work planning.

Many social movements face fierce resistance in the form of a countermovement. Therefore, when deciding to become politically active, a movement supporter has to consider both her own movement’s activity and that of the opponent. This paper studies the decision of a movement supporter to attend a protest when faced with a counterprotest. We implement two field experiments among supporters of a right- and left-leaning movement ahead of two protest–counterprotest interactions in Germany. Supporters were exposed to low or high official estimates about their own and the opposing group’s turnout. We find that the size of the opposing group has no effect on supporters’ protest intentions. However, as the own protest gets larger, supporters of the right-leaning movement become less while supporters of the left-leaning movement become more willing to protest. We argue that the difference is best explained by stronger social motives on the political left.

Garlic mustard [Alliaria petiolata (M. Bieb.) Cavara & Grande] is a biennial invasive plant commonly found in the northeastern and midwestern United States. Although it is not recommended to apply herbicides after flowering, land managers frequently desire to conduct management during this timing. We applied glyphosate and triclopyr (3% v/v and 1% v/v using 31.8% and 39.8% acid equivalent formulations, respectively) POST to established, second-year A. petiolata populations at three locations when petals were dehiscing and evaluated control, seed production, and seed viability. POST glyphosate applications at this timing provided 100% control of A. petiolata by 4 wk after treatment at all locations, whereas triclopyr efficacy was variable, providing 38% to 62% control. Seed production was only reduced at one location, with similar results regardless of treatment. Percent seed viability was also reduced, and when combined with reductions in seed production, resulted in a 71% to 99% reduction in number of viable seeds produced per plant regardless of treatment. While applications did not eliminate viable seed production, our findings indicate that glyphosate and triclopyr applied while petals are dehiscing is a viable alternative to cutting or hand pulling at this timing, as it substantially decreased viable A. petiolata seed production.

An estimator of a finite-dimensional parameter is said to be doubly robust (DR) if it imposes parametric specifications on two unknown nuisance functions, but only requires that one of these two specifications is correct in order for the estimator to be consistent for the object of interest. In this article, we study versions of such estimators that use local polynomial smoothing for estimating the nuisance functions. We show that such semiparametric two-step (STS) versions of DR estimators have favorable theoretical and practical properties relative to other commonly used STS estimators. We also show that these gains are not generated by the DR property alone. Instead, it needs to be combined with an orthogonality condition on the estimation residuals from the nonparametric first stage, which we show to be satisfied in a wide range of models.

Based on a surgical site infection (SSI) cohort at an academic center, we showed a median potentially preventable loss per non-SSI case of $17,916 in colon surgery and of $34,741 in coronary artery bypass grafting.

We study a general class of semiparametric estimators when the infinite-dimensional nuisance parameters include a conditional expectation function that has been estimated nonparametrically using generated covariates. Such estimators are used frequently to e.g., estimate nonlinear models with endogenous covariates when identification is achieved using control variable techniques. We study the asymptotic properties of estimators in this class, which is a nonstandard problem due to the presence of generated covariates. We give conditions under which estimators are root-n consistent and asymptotically normal, derive a general formula for the asymptotic variance, and show how to establish validity of the bootstrap.

Phonological awareness skills are prerequisite to early reading, yet the development of phonological awareness is an understudied phenomenon. To identify factors that contribute to the development of phonological awareness, we investigated the longitudinal relationships among child background factors, structural oral language, and phonological awareness in a sample of 52 children from kindergarten to second grade and a subsample of this group who were nonreaders in kindergarten. Background measures were IQ, family literacy, socioeconomic status, and child's primary language; oral language measures were receptive and expressive semantics, syntax, and morphology; phonological awareness was measured by segmentation and blending. Principal component analysis of the structural language measures yielded a general oral language factor score. Regression analyses indicated that the background variables were unique predictors of kindergarten general oral language skill but did not predict phonological awareness skills. General oral language accounted for significant and substantial unique variance in phonological awareness each year for both the full sample and the subsample of nonreaders, controlling for reading ability. These findings suggest general oral language may contribute to the development of early reading through its significant influence on the development of phonological awareness.

The present study assessed alertness, memory, and performance following three schedules of ∼8 hr of sleep loss (slow, intermediate, and rapid accumulation) in comparison to an 8-hr time in bed (TIB) sleep schedule. Twelve healthy individuals aged 21–35 completed each of four conditions according to a Latin Square design: no sleep loss (8-hr TIB for 4 nights; 2300–0700), slow (6-hr TIB for 4 nights; 0100–0700), intermediate (4-hr TIB for 2 nights; 0300–0700), and rapid (0-hr TIB for 1 night) sleep loss. On each day, participants completed a multiple sleep latency test (MSLT), a probed-recall memory task, a psychomotor vigilance task, a divided attention task, and the Profile of Mood States. “Rapid” sleep loss produced significantly more impairment on tests of alertness, memory, and performance compared to the “slow” accumulation of a comparable amount of sleep loss. The impairing effects of sleep loss vary as a function of rate, suggesting the presence of a compensatory adaptive mechanism operating in conjunction with the accumulation of a sleep debt.