17,343 research outputs found
DRLViz: Understanding Decisions and Memory in Deep Reinforcement Learning
We present DRLViz, a visual analytics interface to interpret the internal
memory of an agent (e.g. a robot) trained using deep reinforcement learning.
This memory is composed of large temporal vectors updated when the agent moves
in an environment and is not trivial to understand due to the number of
dimensions, dependencies to past vectors, spatial/temporal correlations, and
co-correlation between dimensions. It is often referred to as a black box as
only inputs (images) and outputs (actions) are intelligible for humans. Using
DRLViz, experts are assisted to interpret decisions using memory reduction
interactions, and to investigate the role of parts of the memory when errors
have been made (e.g. wrong direction). We report on DRLViz applied in the
context of video games simulators (ViZDoom) for a navigation scenario with item
gathering tasks. We also report on experts evaluation using DRLViz, and
applicability of DRLViz to other scenarios and navigation problems beyond
simulation games, as well as its contribution to black box models
interpretability and explainability in the field of visual analytics
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What motivates academic dishonesty in students? A reinforcement sensitivity theory explanation
BACKGROUND: Academic dishonesty (AD) is an increasing challenge for universities worldwide. The rise of the Internet has further increased opportunities for students to cheat.
AIMS: In this study, we investigate the role of personality traits defined within Reinforcement Sensitivity Theory (RST) as potential determinants of AD. RST defines behaviour as resulting from approach (Reward Interest/reactivity, goal-drive, and Impulsivity) and avoidance (behavioural inhibition and Fight-Flight-Freeze) motivations. We further consider the role of deep, surface, or achieving study motivations in mediating/moderating the relationship between personality and AD.
SAMPLE: A sample of UK undergraduates (N = 240).
METHOD: All participants completed the RST Personality Questionnaire, a short-form version of the study process questionnaire and a measure of engagement in AD, its perceived prevalence, and seriousness.
RESULTS: Results showed that RST traits account for additional variance in AD. Mediation analysis suggested that GDP predicted dishonesty indirectly via a surface study approach while the indirect effect via deep study processes suggested dishonesty was not likely. Likelihood of engagement in AD was positively associated with personality traits reflecting Impulsivity and Fight-Flight-Freeze behaviours. Surface study motivation moderated the Impulsivity effect and achieving motivation the FFFS effect such that cheating was even more likely when high levels of these processes were used.
CONCLUSIONS: The findings suggest that motivational personality traits defined within RST can explain variance in the likelihood of engaging in dishonest academic behaviours
The Power of Linear Recurrent Neural Networks
Recurrent neural networks are a powerful means to cope with time series. We
show how a type of linearly activated recurrent neural networks, which we call
predictive neural networks, can approximate any time-dependent function f(t)
given by a number of function values. The approximation can effectively be
learned by simply solving a linear equation system; no backpropagation or
similar methods are needed. Furthermore, the network size can be reduced by
taking only most relevant components. Thus, in contrast to others, our approach
not only learns network weights but also the network architecture. The networks
have interesting properties: They end up in ellipse trajectories in the long
run and allow the prediction of further values and compact representations of
functions. We demonstrate this by several experiments, among them multiple
superimposed oscillators (MSO), robotic soccer, and predicting stock prices.
Predictive neural networks outperform the previous state-of-the-art for the MSO
task with a minimal number of units.Comment: 22 pages, 14 figures and tables, revised implementatio
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