53,742 research outputs found
Unsupervised Learning of Semantic Orientation from a Hundred-Billion-Word Corpus
The evaluative character of a word is called its semantic orientation. A positive semantic orientation implies desirability (e.g., "honest", "intrepid") and a negative semantic orientation implies undesirability (e.g., "disturbing", "superfluous"). This paper introduces a simple algorithm for unsupervised learning of semantic orientation from extremely large corpora. The method involves issuing queries to a Web search engine and using pointwise mutual information to analyse the results. The algorithm is empirically evaluated using a training corpus of approximately one hundred billion words — the subset of the Web that is indexed by the chosen search engine. Tested with 3,596 words (1,614 positive and 1,982 negative), the algorithm attains an accuracy of 80%. The 3,596 test words include adjectives, adverbs, nouns, and verbs. The accuracy is comparable with the results achieved by Hatzivassiloglou and McKeown (1997), using a complex four-stage supervised learning algorithm that is restricted to determining the semantic orientation of adjectives
Directional Decision Lists
In this paper we introduce a novel family of decision lists consisting of
highly interpretable models which can be learned efficiently in a greedy
manner. The defining property is that all rules are oriented in the same
direction. Particular examples of this family are decision lists with
monotonically decreasing (or increasing) probabilities. On simulated data we
empirically confirm that the proposed model family is easier to train than
general decision lists. We exemplify the practical usability of our approach by
identifying problem symptoms in a manufacturing process.Comment: IEEE Big Data for Advanced Manufacturin
Supplementary skills guides for built environment researchers
Deepening specialised knowledge-base and wider skills of researchers in a wider variety of disciplines are prerequisite for developing successful leadership in higher education, the public sector and industry. In response to
this repeated calls for enhancing supplementary skills of the built environment researchers, TG53 (Postgraduate Research Training in Building and Construction) initiated steps to develop and nurture understanding of
supplementary skills and providing a common frame of reference for use and further discourse and has developed 6 good practice examples highlighting skills for researchers within the built environment. Accordingly, this TG53
publication is in response to the repeated calls for enhancing supplementary skills of the built environment researchers
Modeling Dynamic Swarms
This paper proposes the problem of modeling video sequences of dynamic swarms
(DS). We define DS as a large layout of stochastically repetitive spatial
configurations of dynamic objects (swarm elements) whose motions exhibit local
spatiotemporal interdependency and stationarity, i.e., the motions are similar
in any small spatiotemporal neighborhood. Examples of DS abound in nature,
e.g., herds of animals and flocks of birds. To capture the local spatiotemporal
properties of the DS, we present a probabilistic model that learns both the
spatial layout of swarm elements and their joint dynamics that are modeled as
linear transformations. To this end, a spatiotemporal neighborhood is
associated with each swarm element, in which local stationarity is enforced
both spatially and temporally. We assume that the prior on the swarm dynamics
is distributed according to an MRF in both space and time. Embedding this model
in a MAP framework, we iterate between learning the spatial layout of the swarm
and its dynamics. We learn the swarm transformations using ICM, which iterates
between estimating these transformations and updating their distribution in the
spatiotemporal neighborhoods. We demonstrate the validity of our method by
conducting experiments on real video sequences. Real sequences of birds, geese,
robot swarms, and pedestrians evaluate the applicability of our model to real
world data.Comment: 11 pages, 17 figures, conference paper, computer visio
Changing police culture: raising awareness of the importance of mental health
Master's Project (M.A.) University of Alaska Fairbanks, 2017The suicide rate involving police officers has produced alarming statistics for decades. Until recently, however, little has been done to prevent suicide in law enforcement and even fewer efforts have been made to change the root of the problem. This paper reviews why a law enforcement officer may choose to take their life, looks at preexisting programs and resources that departments can choose to embrace, and supplies departments with a new approach to destigmatizing suicide within the police culture starting at the academy level
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