According to our survey about climate risk perceptions, institutional investors believe climate risks have financial implications for their portfolio firms and that these risks, particularly ...regulatory risks, already have begun to materialize. Many of the investors, especially the long-term, larger, and ESG-oriented ones, consider risk management and engagement, rather than divestment, to be the better approach for addressing climate risks. Although surveyed investors believe that some equity valuations do not fully reflect climate risks, their perceived overvaluations are not large.
Using data on 800,000 corporate publications and patent citations to these publications between 1980 and 2015, we study how corporate investment in research is linked to its use in the firm’s ...inventions, and to spillovers to rivals. We find that private returns to corporate research depend on the balance between two opposing forces: the benefits from the use of science in own downstream inventions, and the costs of spillovers to rivals. Consistent with this, firms produce more research when it is used internally, but less research when it is used by rivals. As firms become more sensitive to rivals using their science, they are likely to reduce the share of research in R&D.
Abstract
Building on signaling theory, the current research proposes an empirical framework to help firms understand the degree to which cross‐category purchases affect the revenue generated for each ...category and how within‐category purchases influence the cross‐category spillover effects. The framework is applied to novel individual‐level, cross‐sectional, and time‐series transaction details from a leading lifestyle conglomerate in the Middle East. The empirical results provide strong support for the presence of revenue spillover across multiple categories of brand extensions, with the spillover being more pronounced in categories in which customers have infrequently purchased and thus had less within‐category experience. These results add to the ongoing stream of research on brand extensions by offering evidence that both within‐ and cross‐category learning play a significant role in revenue generation from brand extensions for multi‐product or service firms.
Learning efficient logic programs Cropper, Andrew; Muggleton, Stephen H.
Machine learning,
07/2019, Letnik:
108, Številka:
7
Journal Article
Recenzirano
Odprti dostop
When machine learning programs from data, we ideally want to learn efficient rather than inefficient programs. However, existing inductive logic programming (ILP) techniques cannot distinguish ...between the efficiencies of programs, such as permutation sort (
n
!) and merge sort
O
(
n
l
o
g
n
)
. To address this limitation, we introduce Metaopt, an ILP system which iteratively learns lower cost logic programs, each time further restricting the hypothesis space. We prove that given sufficiently large numbers of examples, Metaopt converges on minimal cost programs, and our experiments show that in practice only small numbers of examples are needed. To learn minimal time-complexity programs, including non-deterministic programs, we introduce a cost function called
tree cost
which measures the size of the SLD-tree searched when a program is given a goal. Our experiments on programming puzzles, robot strategies, and real-world string transformation problems show that Metaopt learns minimal cost programs. To our knowledge, Metaopt is the first machine learning approach that, given sufficient numbers of training examples, is guaranteed to learn minimal cost logic programs, including minimal time-complexity programs.
We study subgame-perfect implementation (SPI) mechanisms that have been proposed as a solution to incomplete contracting problems. We show that these mechanisms, which are based on off-equilibrium ...arbitration clauses that impose large fines for lying and the inappropriate use of arbitration, have severe behavioral constraints because the fines induce retaliation against legitimate uses of arbitration. Incorporating reciprocity preferences into the theory explains the observed behavioral patterns and helps us develop a new mechanism that is more robust and achieves high rates of truth-telling and efficiency. Our results highlight the importance of tailoring implementation mechanisms to the underlying behavioral environment. (JEL C92, D44, D82, D86, D91)
Abstract
This paper investigates the effect on academic performance of an exogenous educational reform that reduced the school calendar of non‐fee‐paying schools in the Madrid region (Spain) by ...approximately two weeks, leaving the basic curriculum unchanged. To identify the consequences of such a measure, we exploit the fact that it did not affect private schools (control group) and the existence of an external cognitive test that measures academic performance before and after its application in the region. We find that the reform worsened students' educational outcomes by around 0.13 of a standard deviation. This effect was especially strong in the subjects of Spanish and Mathematics. We further explored quantile effects across the distribution of exam scores, finding that the disruption had a more negative effect on students in the upper quartile than those in the lower quartile. Overall, the analysis shows a reduction in the gap across non‐fee‐paying schools and an increase in the gap between non‐fee‐ and fee‐paying schools.
In the infrasonic observation of a fumarolic field, distinguishing multiple fumarolic sources is challenging. The array technique effectively estimates the source locations and identifies the target ...signal from other signals and noise. We conducted an experiment at Kirishima Iwo-Yama, Japan, where two active fumarolic areas were separated by ~ 450 m. A three-element array with an aperture of ~ 20 m was installed between the two fumarolic areas. In addition, a single microphone was installed near one of the fumaroles. The array combined with the waveform correlation analysis estimated the most prominent source but failed to estimate the other weak source. A joint analysis of the array and the single microphone effectively resolved the two sources. It was also confirmed that newly developed power-saving MEMS microphones were useful for observing the fumaroles. This paper presents the instrumentation and analytical method that would be beneficial for monitoring volcanoes that have multiple hydrothermally active vents.
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