When does a referent problem affect willingness to pay for a public good?

In two studies we examined the willingness to support action to remedy a public problem. In Study 1 people were asked whether they would financially contribute to solution of a public problem. In Study 2, people were asked whether they would sign a petition to support a public action. The aim was to test whether the willingness to support solution of a public problem is affected by the type of problem that is used as the referent. We hypothesized that the willingness to support a public action is lower when evaluated in the context of a high - as opposed to a low - importance referent problem (importance contrast effect). We also hypothesized that the importance contrast effect is tied to the perceived relatedness between the target and referent problems. The importance contrast effect should be found only when the two problems relate to different category domains. The findings bear out this prediction.Willingness to support, joint evaluation, referent problem, category-bound thinking.

Growth and integrability of some birational maps in dimension three

Motivated by the study of the Kahan--Hirota--Kimura discretisation of the Euler top, we characterise the growth and integrability properties of a collection of elements in the Cremona group of a complex projective 3-space using techniques from algebraic geometry. This collection consists of maps obtained by composing the standard Cremona transformation $\mathrm{c}_3\in\mathrm{Bir}(\mathbb{P}^3)$ with projectivities that permute the fixed points of $\mathrm{c}_3$ and the points over which $\mathrm{c}_3$ performs a divisorial contraction. More specifically, we show that three behaviour are possible: (A) integrable with quadratic degree growth and two invariants, (B) periodic with two-periodic degree sequences and more than two invariants, and (C) non-integrable with submaximal degree growth and one invariant.Comment: 46 pages, 6 figures, 7 tables, comments are welcom

Individual differences in competent consumer choice: the role of cognitive reflection and numeracy skills

In this paper, we investigate whether cognitive reflection and numeracy skills affect the quality of the consumers’ decision-making process in a purchase decision context. In a first (field) experiment, an identical product was on sale in two shops with different initial prices and discounts. One of the two deals was better than the other and the consumers were asked to choose the best one and to describe which arithmetic operations they used to solve the problem; then they were asked to complete the numeracy scale (Lipkus et al., 2001). The choice procedures used by the consumers were classified as complete decision approach when all the arithmetic operations needed to solve the problem were computed, and as partial decision approach when only some operations were computed. A mediation model shows that higher numeracy is associated with use of the complete decision approach. In turn, this approach is positively associated with the quality of the purchase decision. Given that these findings highlight the importance of the decision processes, in a second (laboratory) experiment we used a supplementary method to study the type of information search used by the participants: eye-tracking. In this experiment the participants were presented with decision problems similar to those used in experiment 1 and they completed the Lipkus numeracy scale and the Cognitive Reflection Test (CRT), (Frederick, 2005). Participants with a high CRT score chose the best deal more frequently, and showed a more profound and detailed information search pattern compared to participants with a low CRT score. Overall, results indicate that higher levels of cognitive reflection and numeracy skills predict the use of a more thorough decision process (measured with two different techniques: retrospective verbal reports and eye movements). In both experiments the decision process is a crucial factor which greatly affects the quality of the purchase decision

Trust and attitude in consumer food choices under risk

In this paper, attitude and trust are studied in the context of a food scare (dioxin) with the aim of identifying the components of attitude and trust that significantly affect how purchases are determined. A revised version of the model by MAYER et al. (1995) was tested for two types of food: salmon and chicken. The final model for salmon shows that trust is significantly determined by perceived competence, perceived shared values, truthfulness of information and the experiential attitude (the feeling that consuming salmon is positive), but trust has no impact on behavioural intentions. Consumer preferences seem to be determined by a positive experiential attitude and the perception that breeders, sellers and institutions have values similar to those of the consumer. The model for chicken gave very similar results.trust, trust antecedents, attitude, food scare, purchase intention, Consumer/Household Economics, Food Consumption/Nutrition/Food Safety, Risk and Uncertainty,

A counterexample to the parity conjecture

Let $[Z]\in\text{Hilb}^d \mathbb A^3$ be a zero-dimensional subscheme of the affine three-dimensional complex space of length $d>0$. Okounkov and Pandharipande have conjectured that the dimension of the tangent space of $\text{Hilb}^d \mathbb A^3$ at $[Z]$ and $d$ have have the same parity. The conjecture was proven by Maulik, Nekrasov, Okounkov and Pandharipande for points $[Z]$ defined by monomial ideals and very recently by Ramkumar and Sammartano for homogeneous ideals. In this paper we exhibit a family of zero-dimensional schemes in $\text{Hilb}^{12} \mathbb A^3$, which disproves the conjecture in the general non-homogeneous case.Comment: 11 pages. Comments are welcom

The geometry of double nested Hilbert schemes of points on curves

Let $C$ be a smooth curve. In this paper we investigate the geometric properties of the double nested Hilbert scheme of points on $C$, a moduli space introduced by the third author in the context of BPS invariants of local curves and sheaf counting on Calabi-Yau 3-folds. We prove this moduli space is connected, reduced and of pure dimension; we list its components via an explicit combinatorial characterisation and we show they can be resolved, when singular, by products of symmetric products of $C$. We achieve this via a purely algebraic analysis of the factorisation properties of the monoid of reverse plane partitions. We discuss the (virtual) fundamental class of the moduli space, we describe the local equations cutting it inside a smooth ambient space, and finally we provide a closed formula for its motivic class in the Grothendieck ring of varieties.Comment: 43 pages, typos fixed, comments welcom

Analisi di movimenti oculari nella risoluzione di problemi commerciali

Many daily purchase decisions, such as choosing the best deal, require the integration of various kinds of information. In most commercial scenarios the consumer has to manage and compare numerical information. The present study is driven by an important research question: “in a commercial scenario with a high numerical component, is numerical ability (e.g. numeracy) the only factor that influences the accuracy of decisions?”. The aim of the present paper is to understand if cognitive reflection drives the problem-solving process in these contexts. We examined attentional aspects by measuring eye movements using an SR Research Eye Link 1000 eye tracking device belonging to The Consumer Neuroscience Laboratory (ncLab) located at The University of Trento

Zero-dimensional sheaves, group actions and blowups

The main objects of study of this thesis are 0-dimensional subschemes of affine spaces. More precisely, I have studied the following two aspects concerning them: • the interaction between 0-dimensional subschemes and linear group actions on An , • the computation of the Behrend number of 0-dimensional schemes in order to better understand the Hilbert scheme of points. In the first chapter of the thesis I have constructed the moduli spaces of certainG -equivariant coherent O A2-modules (G -constellations), introduced by Alastair Craw in 2001, which are stable with respect to a GIT stability condition. In addition, I studied the associated chamber decomposition giving an explicit combinatorial description of the chambers. In the second part of the thesis I have computed, mostly applying techniques from toric geometry, the Behrend number of a large number of fat points of the affine plane. This invariant had been abstractly defined by Behrend in 2009, but even for a scheme with only one point the (few) existing methods to calculate it could not be applied. The thesis is mainly based on the content of the following two preprints: • “Moduli spaces of Z/kZ-constellations over A2". [30, 2022] • “On the Behrend function and the blowup of some fat points", with A. T. Ricolfi.[31, 2022

Koszul cohomology and Hilbert schemes of points

Since 1984, year in which it was rst formulated, Green's conjecture has been object of study in algebraic geometry research: my master thesis is devoted to Clair Voisin's solution to such problem. In particular, Green's conjecture solution stems, as a corollary, from a more general theorem by Voisin. The most relevant concepts this thesis touches upon are: Hilbert schemes of point, the Cayley-Bacharach property, the Mukai-Lazarsfeld bundle, the Koszul cohomology and the K3 surfaces. Being this work a descriptive thesis, it does not lead to any innovative results. However, having built and proved myself most of the theorems and demonstrations covered in the first three chapters, I managed to get in-depth knowledge and get considerably familiarised with many tools and topics typical of modern algebraic geometry. This thesis contributes to the literature in that it is, leaving Aprodu & Nagel ([2010] chapters 4-6) and Voisin ([2002]) aside, the rst paper fully dedicated to the theorem. This means that it extensively articulates crucial aspects of the theory that Voisin ([2002]) only quickly touches upon. In particular, to work on this thesis allowed me to study concepts and focus on some research areas that I had not have the chance to study during my bachelor and master classes