11,023 research outputs found
Functional advantages offered by many-body coherences in biochemical systems
Quantum coherence phenomena driven by electronic-vibrational (vibronic)
interactions, are being reported in many pulse (e.g. laser) driven chemical and
biophysical systems. But what systems-level advantage(s) do such many-body
coherences offer to future technologies? We address this question for pulsed
systems of general size N, akin to the LHCII aggregates found in green plants.
We show that external pulses generate vibronic states containing particular
multipartite entanglements, and that such collective vibronic states increase
the excitonic transfer efficiency. The strength of these many-body coherences
and their robustness to decoherence, increase with aggregate size N and do not
require strong electronic-vibrational coupling. The implications for energy and
information transport are discussed.Comment: arXiv admin note: text overlap with arXiv:1706.0776
Human-Aligned Calibration for AI-Assisted Decision Making
Whenever a binary classifier is used to provide decision support, it
typically provides both a label prediction and a confidence value. Then, the
decision maker is supposed to use the confidence value to calibrate how much to
trust the prediction. In this context, it has been often argued that the
confidence value should correspond to a well calibrated estimate of the
probability that the predicted label matches the ground truth label. However,
multiple lines of empirical evidence suggest that decision makers have
difficulties at developing a good sense on when to trust a prediction using
these confidence values. In this paper, our goal is first to understand why and
then investigate how to construct more useful confidence values. We first argue
that, for a broad class of utility functions, there exist data distributions
for which a rational decision maker is, in general, unlikely to discover the
optimal decision policy using the above confidence values -- an optimal
decision maker would need to sometimes place more (less) trust on predictions
with lower (higher) confidence values. However, we then show that, if the
confidence values satisfy a natural alignment property with respect to the
decision maker's confidence on her own predictions, there always exists an
optimal decision policy under which the level of trust the decision maker would
need to place on predictions is monotone on the confidence values, facilitating
its discoverability. Further, we show that multicalibration with respect to the
decision maker's confidence on her own predictions is a sufficient condition
for alignment. Experiments on four different AI-assisted decision making tasks
where a classifier provides decision support to real human experts validate our
theoretical results and suggest that alignment may lead to better decisions
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