The effect of transparency on recognition of overlapping objects

Are overlapping objects easier to recognize when the objects are transparent or opaque? It is important to know whether the transparency of X-ray images of luggage contributes to the difficulty in searching those images for targets. Transparency provides extra information about objects that would normally be occluded but creates potentially ambiguous depth relations at the region of overlap. Two experiments investigated the threshold durations at which adult participants could accurately name pairs of overlapping objects that were opaque or transparent. In Experiment 1, the transparent displays included monocular cues to relative depth. Recognition of the back object was possible at shorter durations for transparent displays than for opaque displays. In Experiment 2, the transparent displays had no monocular depth cues. There was no difference in the duration at which the back object was recognized across transparent and opaque displays. The results of the two experiments suggest that transparent displays, even though less familiar than opaque displays, do not make object recognition more difficult, and possibly show a benefit. These findings call into question the importance of edge junctions in object recognitio

Why did the bankers behave so badly?

It is widely believed that bankers played an important role in causing the financial crisis that began in August 2007. In this paper we demonstrate that the compensation system in the financial services industry which rewards perceived talents, rather than long-term performance, leads rational bankers to exhibit belief persistence, overconfidence and confirmation bias

Some theoretical and methodological comments on the impact of policies on fertility

Theoretically, and for reasons that I will shortly summarise in this presentation, there are strong reasons to expect policies to have a positive impact on fertility. Empirically, however, the evidence regarding the potential impact of policies of fertility is less clear cut. While numerous studies do indeed show a positive impact of policies, there is no consensus regarding the actual magnitude of the impact, nor about its short- or medium-term nature (Gauthier 2007). What I want to do in this presentation is consequently to reflect on the results from empirical studies by raising a number of theoretical and methodological issues.

On minors of maximal determinant matrices

By an old result of Cohn (1965), a Hadamard matrix of order n has no proper Hadamard submatrices of order m > n/2. We generalise this result to maximal determinant submatrices of Hadamard matrices, and show that an interval of length asymptotically equal to n/2 is excluded from the allowable orders. We make a conjecture regarding a lower bound for sums of squares of minors of maximal determinant matrices, and give evidence in support of the conjecture. We give tables of the values taken by the minors of all maximal determinant matrices of orders up to and including 21 and make some observations on the data. Finally, we describe the algorithms that were used to compute the tables.Comment: 35 pages, 43 tables, added reference to Cohn in v

Government Budget Deficits in Large Open Economies

Large and growing levels of public debt in the United States, United Kingdom, Japan and the Euro Area raise new interest in the cross-country effects of a large open economy’s deficits. We consider a dynamic optimising model with costly tax collection and exogenously given public spending and initial debt. We ask whether the externalities associated with an individual country’s deficits are positive or negative. We characterise the path of taxes in the Nash equilibrium where policy makers act nationalistically and compare this outcome to the global optimal outcome.fiscal policy, international policy coordination, optimal taxation

Can policies enhance fertility in Europe?

Not found