New heuristics for the stochastic tactical railway maintenance problem

Efficient methods have been proposed in the literature for the management of a set of railway maintenance operations. However, these methods consider maintenance operations as deterministic and known a priori. In the stochastic tactical railway maintenance problem (STRMP), maintenance operations are not known in advance. In fact, since future track conditions can only be predicted, maintenance operations become stochastic. STRMP is based on a rolling horizon. For each month of the rolling horizon, an adaptive plan must be addressed. Each adaptive plan becomes deterministic, since it consists of a particular subproblem of the whole STRMP. Nevertheless, an exact resolution of each plan along the rolling horizon would be too time-consuming. Therefore, a heuristic approach that can provide efficient solutions within a reasonable computational time is required. Although STRMP has already been introduced in the literature, little work has been done in terms of solution methods and computational results. The main contributions of this paper include new methodology developments, a linear model for the deterministic subproblem, three efficient heuristics for the fast and effective resolution of each deterministic subproblem, and extensive computational results

Lying in Two Dimensions and Moral Spillovers

The expanding literature on lying has exclusively considered lying behavior within a one-dimensional context. While this has been an important first step, many real-world contexts involve the possibility of simultaneously lying in more than one dimension (e.g., reporting one’s income and expenses in a tax declaration). In this paper, we experimentally investigate individual lying behavior in both one- and two-dimensional contexts to understand whether the multi-dimensionality of a decision affects lying behavior. In the one-dimensional treatment, participants are asked to roll two dice in one hand and to report the sum of both dice. In the two-dimensional treatment, participants are asked to roll two dice at the same time, but one in each hand, and to report the two dice separately. Our paper provides the first evidence regarding lying behavior in a multi-dimensional context. Using a two-dimensional die-roll task, we show that participants lie partially between dimensions, which results in greater overreporting of the lower outcome die. These findings suggest a thought-provoking policy to tackle the infamous societal challenge of tax fraud: Tax report checks should focus on the item(s) for which a taxpayer profile hints at higher self-benefits in case of misreporting

Incentivized choice in large-scale voting experiments

Survey experiments that investigate how voting procedures affect voting behavior and election outcomes use hypothetical questions and non-representative samples. We present here the results of a novel survey experiment that addresses both concerns. First, the winning party in our experiment receives a donation to its campaign funds inducing real consequences for voting. Second, we run an online experiment with a Dutch national representative sample (N = 1240). Our results validate previous findings using a representative sample, in particular that approval voting leads to a higher concentration in votes for smaller parties and strengthens centrist parties in comparison to plurality voting. Importantly, our results suggest that voting behavior is not affected by voting incentives and can be equally reliably elicited with hypothetical questions

Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences

The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & Nemésio 2007; Donegan 2008, 2009; Nemésio 2009a–b; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on 18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based researchers who signed it in the short time span from 20 September to 6 October 2016

Identification of genetic variants associated with Huntington's disease progression: a genome-wide association study

Background Huntington's disease is caused by a CAG repeat expansion in the huntingtin gene, HTT. Age at onset has been used as a quantitative phenotype in genetic analysis looking for Huntington's disease modifiers, but is hard to define and not always available. Therefore, we aimed to generate a novel measure of disease progression and to identify genetic markers associated with this progression measure. Methods We generated a progression score on the basis of principal component analysis of prospectively acquired longitudinal changes in motor, cognitive, and imaging measures in the 218 indivduals in the TRACK-HD cohort of Huntington's disease gene mutation carriers (data collected 2008–11). We generated a parallel progression score using data from 1773 previously genotyped participants from the European Huntington's Disease Network REGISTRY study of Huntington's disease mutation carriers (data collected 2003–13). We did a genome-wide association analyses in terms of progression for 216 TRACK-HD participants and 1773 REGISTRY participants, then a meta-analysis of these results was undertaken. Findings Longitudinal motor, cognitive, and imaging scores were correlated with each other in TRACK-HD participants, justifying use of a single, cross-domain measure of disease progression in both studies. The TRACK-HD and REGISTRY progression measures were correlated with each other (r=0·674), and with age at onset (TRACK-HD, r=0·315; REGISTRY, r=0·234). The meta-analysis of progression in TRACK-HD and REGISTRY gave a genome-wide significant signal (p=1·12 × 10−10) on chromosome 5 spanning three genes: MSH3, DHFR, and MTRNR2L2. The genes in this locus were associated with progression in TRACK-HD (MSH3 p=2·94 × 10−8 DHFR p=8·37 × 10−7 MTRNR2L2 p=2·15 × 10−9) and to a lesser extent in REGISTRY (MSH3 p=9·36 × 10−4 DHFR p=8·45 × 10−4 MTRNR2L2 p=1·20 × 10−3). The lead single nucleotide polymorphism (SNP) in TRACK-HD (rs557874766) was genome-wide significant in the meta-analysis (p=1·58 × 10−8), and encodes an aminoacid change (Pro67Ala) in MSH3. In TRACK-HD, each copy of the minor allele at this SNP was associated with a 0·4 units per year (95% CI 0·16–0·66) reduction in the rate of change of the Unified Huntington's Disease Rating Scale (UHDRS) Total Motor Score, and a reduction of 0·12 units per year (95% CI 0·06–0·18) in the rate of change of UHDRS Total Functional Capacity score. These associations remained significant after adjusting for age of onset. Interpretation The multidomain progression measure in TRACK-HD was associated with a functional variant that was genome-wide significant in our meta-analysis. The association in only 216 participants implies that the progression measure is a sensitive reflection of disease burden, that the effect size at this locus is large, or both. Knockout of Msh3 reduces somatic expansion in Huntington's disease mouse models, suggesting this mechanism as an area for future therapeutic investigation

Essays on self-image and preferences for honesty

The act of lying has always fascinated societies and researchers because opportunities to lie for the own benefit are prevalent in many areas of people's daily lives. In many of these situations, lies are socially undesirable and bear consequences for individuals and society as a whole. This thesis contributes to a growing literature which attempts to broaden our understanding of dishonesty and to yield meaningful insights on how to increase honesty in economic interactions. The chapters of this thesis focus on the role of self-image in the decision to tell a lie and explore the relationship between self-image and honesty to answer two main questions. How do self-image concerns explain differences in lying between different settings and what is the role of self-image concerns in decreasing dishonesty? People have an interest in holding a positive self-image and take actions which enable them to have a positive attitude towards themselves. Thus, self-image concerns also affect the decision to tell a lie or to make a truthful statement. On the one hand, this thesis addresses situations where the desire to think well about the own person increases honesty because people like to think of themselves as honest and moral decision makers. On the other hand, this thesis also considers situations where self-image concerns decrease honesty because by admitting the truth people would have to reveal information which makes them feel bad about themselves. In addition to reflecting on the role of self-image in the decision to lie, this work also focuses on how insights into the relationship of self-image and honesty can help to reduce dishonesty. In the case of self-image concerns increasing honesty, this can be done by increasing the negative feeling caused by telling a lie. Otherwise, lying can be reduced by providing an appropriate monetary payoff which counteracts the harm to the self-image caused by the truthful statement

Untersuchung von heuristischen Optimierungsverfahren zur hierarchischen Platzierung von Standardzellen in 3D-Aufbauten

nicht vorhande

Untersuchung von heuristischen Optimierungsverfahren zur hierarchischen Platzierung von Standardzellen in 3D-Aufbauten

nicht vorhande

Lying in two dimensions

The expanding literature on lying has exclusively considered lying behavior within a one-dimensional context. While this has been an important first step, many real-world contexts involve the possibility of simultaneously lying in more than one dimension (e.g., reporting one’s income and expenses in a tax declaration). We experimentally investigate individual lying behavior in one- and two-dimensional contexts to understand how the multi-dimensionality of a decision affects lying behavior. Our paper provides the first evidence regarding the pure effect of dimensionality on lying behavior. Using a two-dimensional die-roll task, we show that participants distribute lies unevenly across dimensions, which results in greater over-reporting of the lower-outcome die

The effect of pledges on the distribution of lying behavior: An online experiment

Reminding people to behave honestly or asking them to actively commit to honest behavior is an easily implementable intervention to reduce dishonesty. Earlier research has shown that such truth pledges affect lying behavior on a group level. In this study we are analyzing how a truth pledge changes the distribution of lying types which have been established in the literature, i.e. truth tellers, partial liars and extreme liars, to better understand whether truth pledges can affect the decision to lie or merely the extent of lies. For this purpose, we conduct a 2 × 2 experiment with 484 participants in which we apply a truth pledge in a gain and a loss frame. We introduce a novel “Even-Odd task” for online lying experiments, which is based on the well-established coin-toss design. The Even-Odd task takes into account that unbiased, physical randomization devices are not always available in online settings, which can be a problem for truth-tellers if they are bad mental randomizers. We therefore ask participants to think of privately known numbers (house numbers, phone numbers) and then determine randomly whether even or uneven numbers result in the higher payment. We find that the truth pledge significantly reduces lying but also that this effect is strongest for extreme liars. The uneven shift in the distribution of liars suggests that truth pledges are effective in decreasing the size of lies but not the number of lies told. This result is robust for both frames