This paper presents a novel approach to perform sentiment analysis of news videos, based on the fusion of audio, textual and visual clues extracted from their contents. The proposed approach aims at contributing to the semiodiscoursive study regarding the construction of the ethos (identity) of this media universe, which has become a central part of the modern-day lives of millions of people. To achieve this goal, we apply state-of-the-art computational methods for (1) automatic emotion recognition from facial expressions, (2) extraction of modulations in the participants' speeches and (3) sentiment analysis from the closed caption associated to the videos of interest. More specifically, we compute features, such as, visual intensities of recognized emotions, field sizes of participants, voicing probability, sound loudness, speech fundamental frequencies and the sentiment scores (polarities) from text sentences in the closed caption. Experimental results with a dataset containing 520 annotated news videos from three Brazilian and one American popular TV newscasts show that our approach achieves an accuracy of up to 84% in the sentiments (tension levels) classification task, thus demonstrating its high potential to be used by media analysts in several applications, especially, in the journalistic domain.

This study analyzes different methodological approaches followed in social media literature and their accuracy in predicting the general elections of four countries. Volumetric and unsupervised and supervised sentiment approaches are adopted for generating 12 metrics to compute predicted voteshares. The findings suggest that Twitter-based predictions can produce accurate results for elections, given the digital environment of a country. A cross-country analyses helps to evaluate the quality of predictions and the influence of different contexts, such as technological development and democratic setups. We recommend future scholars to combine volume, sentiment and network aspects of social media to model voting intentions in developing societies.

We propose a new pooling technique for topic modeling in Twitter, which groups together tweets occurring in the same user-to-user conversation. Under this scheme, tweets and their replies are aggregated into a single document and the users who posted them are considered co-authors. To compare this new scheme against existing ones, we train topic models using Latent Dirichlet Allocation (LDA) and the Author-Topic Model (ATM) on datasets consisting of tweets pooled according to the different methods. Using the underlying categories of the tweets in this dataset as a noisy ground truth, we show that this new technique outperforms other pooling methods in terms of clustering quality and document retrieval.

A lot of discussion around Matt Jockers' Syuzhet package (involving Annie Swafford, Ted Underwood, Andrew Piper, Scott Weingart and many others) has focused on issues of validity -- whether sentiment analysis is accurate enough for the task, whether the Fourier transform is an appropriate method for dimensionality reduction, whether the emotional trajectories themselves are valid measurements of anything at all (Scott has a good enumeration of the various issues here.) Andrew's discussion of the validity of inherently subjective measurements inspired me to solicit at least one data point from readers that we can use for one question under discussion with Syuzhet: what does a human judgment of the "emotional trajectory" of a work look like, and how often do readers agree with each other on this task? This method of soliciting human judgments for inherently subjective tasks is at the core of NLP and a lot of machine learning -- syntactic parsing, part of speech tagging, named entity recognition, topic classification, sentiment analysis, and lots of other tasks all rely on humans making judgments that are often surprisingly difficult in practice; learning algorithms in these cases are not so much learning any notion of "truth" but simply to reproduce the human judgments they're given. Agreement rates between humans is often seen as a proxy for the complexity of the task; if humans can't agree, it can be a sign that the task is ill-defined or underspecified. Word sense disambiguation is one good example of this, with low inter-annotator agreement rates [Snyder and Palmer 2004]; while sentiment analysis was originally designed with product/movie reviews in mind (does person X like product Y?) -- i.e., attitude with respect to a particular target -- I think the more general sentiment-as-tone problem (is this tweet happy or sad?) is much less well specified as a problem with an answer that can be judged by anyone but the original author. One aspect of those kind of annotations that I think is much less explored (which Piper points to and I think would be an extremely interesting area to work on) is the case where multiple judgments are simultaneously valid -- different interpretations of the same phenomenon, each backed by their own argument.

What are the limits of automated Twitter sentiment classification? We analyze a large set of manually labeled tweets in different languages, use them as training data, and construct automated classification models. It turns out that the quality of classification models depends much more on the quality and size of training data than on the type of the model trained. Experimental results indicate that there is no statistically significant difference between the performance of the top classification models. We quantify the quality of training data by applying various annotator agreement measures, and identify the weakest points of different datasets. We show that the model performance approaches the inter-annotator agreement when the size of the training set is sufficiently large. However, it is crucial to regularly monitor the self- and inter-annotator agreements since this improves the training datasets and consequently the model performance. Finally, we show that there is strong evidence that humans perceive the sentiment classes (negative, neutral, and positive) as ordered.

I want to play around with twitter sentiment analysis and my main hesitation is on obtaining a dataset that's been classified for supervised learning. Do you know if a decent one exists already, or would I have to create one myself (or use mechical turk)?

Machine learning makes sentiment analysis more convenient. This post would introduce how to do sentiment analysis with machine learning using R. In the landscape of R, the sentiment R package and the more general text mining package have been well developed by Timothy P. Jurka. You can check out the sentiment package and the fantastic RTextTools package. Actually, Timothy also writes an maxent package for low-memory multinomial logistic regression (also known as maximum entropy).

With the big data growing bigger and bigger and social media penetrating every facet of the society, construing and monitoring data is one of the biggest challenges faced by the enterprises. Gone are those days when customers have to lodge a formal complaint to register the malfunctioning of any product/services provided by the business enterprise, rather, users these days take it to the social media forum to express their dissatisfaction and anguish towards any improper services/products. Inputs such as tweets, facebook comments could be of significant value to the enterprise to analyze their products/services/ performances, customer behavior and demands. Below is a small case study on Flipkart and Snapdeal performance when'World Book Day' was trending on Twitter. Below is the screenshot of'Flipkart' and'Snapdeal' on the occasion of'World Book Day'.

This blog was originally published on our Text Analysis blog, the blog post set out to analyze and visualize 4 million tweets collected during Superbowl XLIX. Not surprisingly, Superbowl XLIX generated a huge amount of chatter on social networks with Twitter Estimating that over 28.4 million posts made with terms relating to the Superbowl. At AYLIEN, we collected just under 4 million Tweets from Hashtags, Handles and Keywords we were monitoring. To keep our sample clean, we removed any reTweets and spam from the Tweets collected and only worked with those Tweets that were written in English. We were left with about 3.5 million Tweets to play with.

In just minutes Corom adds Machine Learning intelligence to a chat app, adding emoji based on a sentiment analysis of the text!