10,374 research outputs found
Learning sentiment from studentsâ feedback for real-time interventions in classrooms
Knowledge about users sentiments can be used for a variety of adaptation purposes. In the case of teaching, knowledge about students sentiments can be used to address problems like confusion and boredom which affect students engagement. For this purpose, we looked at several methods that could be used for learning sentiment from students feedback. Thus, Naive Bayes, Complement Naive Bayes (CNB), Maximum Entropy and Support Vector Machine (SVM) were trained using real students' feedback. Two classifiers stand out as better at learning sentiment, with SVM resulting in the highest accuracy at 94%, followed by CNB at 84%. We also experimented with the use of the neutral class and the results indicated that, generally, classifiers perform better when the neutral class is excluded
Finding Street Gang Members on Twitter
Most street gang members use Twitter to intimidate others, to present
outrageous images and statements to the world, and to share recent illegal
activities. Their tweets may thus be useful to law enforcement agencies to
discover clues about recent crimes or to anticipate ones that may occur.
Finding these posts, however, requires a method to discover gang member Twitter
profiles. This is a challenging task since gang members represent a very small
population of the 320 million Twitter users. This paper studies the problem of
automatically finding gang members on Twitter. It outlines a process to curate
one of the largest sets of verifiable gang member profiles that have ever been
studied. A review of these profiles establishes differences in the language,
images, YouTube links, and emojis gang members use compared to the rest of the
Twitter population. Features from this review are used to train a series of
supervised classifiers. Our classifier achieves a promising F1 score with a low
false positive rate.Comment: 8 pages, 9 figures, 2 tables, Published as a full paper at 2016
IEEE/ACM International Conference on Advances in Social Networks Analysis and
Mining (ASONAM 2016
Colour consistency in computer vision : a multiple image dynamic exposure colour classification system : a thesis presented to the Institute of Natural and Mathematical Sciences in fulfilment of the requirements for the degree of Master of Science in Computer Science at Massey University, Albany, Auckland, New Zealand
Colour classification vision systems face difficulty when a scene contains both very
bright and dark regions. An indistinguishable colour at one exposure may be
distinguishable at another. The use of multiple cameras with varying levels of
sensitivity is explored in this thesis, aiding the classification of colours in scenes with
high illumination ranges. Titled the Multiple Image Dynamic Exposure Colour
Classification (MIDECC) System, pie-slice classifiers are optimised for normalised
red/green and cyan/magenta colour spaces. The MIDECC system finds a limited section
of hyperspace for each classifier, resulting in a process which requires minimal manual
input with the ability to filter background samples without specialised training. In
experimental implementation, automatic multiple-camera exposure, data sampling,
training and colour space evaluation to recognise 8 target colours across 14 different
lighting scenarios is processed in approximately 30 seconds. The system provides
computationally effective training and classification, outputting an overall true positive
score of 92.4% with an illumination range between bright and dim regions of 880 lux.
False positive classifications are minimised to 4.24%, assisted by heuristic background
filtering. The limited search space classifiers and layout of the colour spaces ensures the
MIDECC system is less likely to classify dissimilar colours, requiring a certain
âconfidenceâ level before a match is outputted. Unfortunately the system struggles to
classify colours under extremely bright illumination due to the simplistic classification
building technique. Results are compared to the common machine learning algorithms
NaĂŻve Bayes, Neural Networks, Random Tree and C4.5 Tree Classifiers. These
algorithms return greater than 98.5% true positives and less than 1.53% false positives,
with Random Tree and NaĂŻve Bayes providing the best and worst comparable
algorithms, respectively. Although resulting in a lower classification rate, the MIDECC
system trains with minimal user input, ignores background and untrained samples when
classifying and trains faster than most of the studied machine learning algorithms.Colour classification vision systems face difficulty when a scene contains both very
bright and dark regions. An indistinguishable colour at one exposure may be
distinguishable at another. The use of multiple cameras with varying levels of
sensitivity is explored in this thesis, aiding the classification of colours in scenes with
high illumination ranges. Titled the Multiple Image Dynamic Exposure Colour
Classification (MIDECC) System, pie-slice classifiers are optimised for normalised
red/green and cyan/magenta colour spaces. The MIDECC system finds a limited section
of hyperspace for each classifier, resulting in a process which requires minimal manual
input with the ability to filter background samples without specialised training. In
experimental implementation, automatic multiple-camera exposure, data sampling,
training and colour space evaluation to recognise 8 target colours across 14 different
lighting scenarios is processed in approximately 30 seconds. The system provides
computationally effective training and classification, outputting an overall true positive
score of 92.4% with an illumination range between bright and dim regions of 880 lux.
False positive classifications are minimised to 4.24%, assisted by heuristic background
filtering. The limited search space classifiers and layout of the colour spaces ensures the
MIDECC system is less likely to classify dissimilar colours, requiring a certain
âconfidenceâ level before a match is outputted. Unfortunately the system struggles to
classify colours under extremely bright illumination due to the simplistic classification
building technique. Results are compared to the common machine learning algorithms
NaĂŻve Bayes, Neural Networks, Random Tree and C4.5 Tree Classifiers. These
algorithms return greater than 98.5% true positives and less than 1.53% false positives,
with Random Tree and NaĂŻve Bayes providing the best and worst comparable
algorithms, respectively. Although resulting in a lower classification rate, the MIDECC
system trains with minimal user input, ignores background and untrained samples when
classifying and trains faster than most of the studied machine learning algorithms
Addressee Identification In Face-to-Face Meetings
We present results on addressee identification in four-participants face-to-face meetings using Bayesian Network and Naive Bayes classifiers. First, we investigate how well the addressee of a dialogue act can be predicted based on gaze, utterance and conversational context features. Then, we explore whether information about meeting context can aid classifiersâ performances. Both classifiers perform the best when conversational context and utterance features are combined with speakerâs gaze information. The classifiers show little gain from information about meeting context
A traffic classification method using machine learning algorithm
Applying concepts of attack investigation in IT industry, this idea has been developed to design
a Traffic Classification Method using Data Mining techniques at the intersection of Machine
Learning Algorithm, Which will classify the normal and malicious traffic. This classification will
help to learn about the unknown attacks faced by IT industry. The notion of traffic classification
is not a new concept; plenty of work has been done to classify the network traffic for
heterogeneous application nowadays. Existing techniques such as (payload based, port based
and statistical based) have their own pros and cons which will be discussed in this
literature later, but classification using Machine Learning techniques is still an open field to explore and has provided very promising results up till now
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