Automated Text Analysis

Automated and computer-assisted methods of extracting, organizing, and consuming knowledge from unstructured text.

Content Analysis

General Purpose Computer-Assisted Clustering and Conceptualization
Grimmer, Justin, and Gary King. 2011. General Purpose Computer-Assisted Clustering and Conceptualization, Proceedings of the National Academy of Sciences. Publisher's VersionAbstract
We develop a computer-assisted method for the discovery of insightful conceptualizations, in the form of clusterings (i.e., partitions) of input objects. Each of the numerous fully automated methods of cluster analysis proposed in statistics, computer science, and biology optimize a different objective function. Almost all are well defined, but how to determine before the fact which one, if any, will partition a given set of objects in an "insightful" or "useful" way for a given user is unknown and difficult, if not logically impossible. We develop a metric space of partitions from all existing cluster analysis methods applied to a given data set (along with millions of other solutions we add based on combinations of existing clusterings), and enable a user to explore and interact with it, and quickly reveal or prompt useful or insightful conceptualizations. In addition, although uncommon in unsupervised learning problems, we offer and implement evaluation designs that make our computer-assisted approach vulnerable to being proven suboptimal in specific data types. We demonstrate that our approach facilitates more efficient and insightful discovery of useful information than either expert human coders or many existing fully automated methods.
An Automated Information Extraction Tool For International Conflict Data with Performance as Good as Human Coders: A Rare Events Evaluation Design
Methods to evaluate automated information extraction systems when coding rare events, the success of one such system, along with considerable data. King, Gary, and Will Lowe. 2003. An Automated Information Extraction Tool For International Conflict Data with Performance as Good as Human Coders: A Rare Events Evaluation Design, International Organization 57: 617-642.Abstract
Despite widespread recognition that aggregated summary statistics on international conflict and cooperation miss most of the complex interactions among nations, the vast majority of scholars continue to employ annual, quarterly, or occasionally monthly observations. Daily events data, coded from some of the huge volume of news stories produced by journalists, have not been used much for the last two decades. We offer some reason to change this practice, which we feel should lead to considerably increased use of these data. We address advances in event categorization schemes and software programs that automatically produce data by "reading" news stories without human coders. We design a method that makes it feasible for the first time to evaluate these programs when they are applied in areas with the particular characteristics of international conflict and cooperation data, namely event categories with highly unequal prevalences, and where rare events (such as highly conflictual actions) are of special interest. We use this rare events design to evaluate one existing program, and find it to be as good as trained human coders, but obviously far less expensive to use. For large scale data collections, the program dominates human coding. Our new evaluative method should be of use in international relations, as well as more generally in the field of computational linguistics, for evaluating other automated information extraction tools. We believe that the data created by programs similar to the one we evaluated should see dramatically increased use in international relations research. To facilitate this process, we are releasing with this article data on 4.3 million international events, covering the entire world for the last decade.
How Censorship in China Allows Government Criticism but Silences Collective Expression
King, Gary, Jennifer Pan, and Margaret E Roberts. 2013. How Censorship in China Allows Government Criticism but Silences Collective Expression, American Political Science Review 107, no. 2 (May): 1-18.Abstract
We offer the first large scale, multiple source analysis of the outcome of what may be the most extensive effort to selectively censor human expression ever implemented. To do this, we have devised a system to locate, download, and analyze the content of millions of social media posts originating from nearly 1,400 different social media services all over China before the Chinese government is able to find, evaluate, and censor (i.e., remove from the Internet) the large subset they deem objectionable. Using modern computer-assisted text analytic methods that we adapt to and validate in the Chinese language, we compare the substantive content of posts censored to those not censored over time in each of 85 topic areas. Contrary to previous understandings, posts with negative, even vitriolic, criticism of the state, its leaders, and its policies are not more likely to be censored. Instead, we show that the censorship program is aimed at curtailing collective action by silencing comments that represent, reinforce, or spur social mobilization, regardless of content. Censorship is oriented toward attempting to forestall collective activities that are occurring now or may occur in the future --- and, as such, seem to clearly expose government intent.
<p>Computer-Assisted Keyword and Document Set Discovery from Unstructured Text</p>
King, Gary, Patrick Lam, and Margaret Roberts. 2014.

Computer-Assisted Keyword and Document Set Discovery from Unstructured Text

.Abstract
The (unheralded) first step in many applications of automated text analysis involves selecting keywords to choose documents from a large text corpus for further study. Although all substantive results depend crucially on this choice, researchers typically pick keywords in ad hoc ways, given the lack of formal statistical methods to help. Paradoxically, this often means that the validity of the most sophisticated text analysis methods depends in practice on the inadequate keyword counting or matching methods they are designed to replace. The same ad hoc keyword selection process is also used in many other areas, such as following conversations that rapidly innovate language to evade authorities, seek political advantage, or express creativity; generic web searching; eDiscovery; look-alike modeling; intelligence analysis; and sentiment and topic analysis. We develop a computer-assisted (as opposed to fully automated) statistical approach that suggests keywords from available text, without needing any structured data as inputs. This framing poses the statistical problem in a new way, which leads to a widely applicable algorithm. Our specific approach is based on training classifiers, extracting information from (rather than correcting) their mistakes, and then summarizing results with Boolean search strings. We illustrate how the technique works with examples in English and Chinese.
King, Gary, and Justin Grimmer. Method and Apparatus for Selecting Clusterings to Classify A Predetermined Data Set. U.S. Patent and Trademark Office. US Patent 8,438,162, filed 2013.Abstract
A method for selecting clusterings to classify a predetermined data set of numerical data comprises five steps. First, a plurality of known clustering methods are applied, one at a time, to the data set to generate clusterings for each method. Second, a metric space of clusterings is generated using a metric that measures the similarity between two clusterings. Third, the metric space is projected to a lower dimensional representation useful for visualization. Fourth, a “local cluster ensemble” method generates a clustering for each point in the lower dimensional space. Fifth, an animated visualization method uses the output of the local cluster ensemble method to display the lower dimensional space and to allow a user to move around and explore the space of clustering.
<p>Reverse-engineering censorship in China: Randomized experimentation and participant observation</p>
King, Gary, Jennifer Pan, and Margaret E Roberts. 2014.

Reverse-engineering censorship in China: Randomized experimentation and participant observation

, Science 345, no. 6199: 1-10. Publisher's VersionAbstract
Existing research on the extensive Chinese censorship organization uses observational methods with well-known limitations. We conducted the first large-scale experimental study of censorship by creating accounts on numerous social media sites, randomly submitting different texts, and observing from a worldwide network of computers which texts were censored and which were not. We also supplemented interviews with confidential sources by creating our own social media site, contracting with Chinese firms to install the same censoring technologies as existing sites, and—with their software, documentation, and even customer support—reverse-engineering how it all works. Our results offer rigorous support for the recent hypothesis that criticisms of the state, its leaders, and their policies are published, whereas posts about real-world events with collective action potential are censored.
<p>A Method of Automated Nonparametric Content Analysis for Social Science</p>
A method that gives unbiased estimates of the proportion of text documents in investigator-chosen categories, given only a small subset of hand-coded documents. Also includes the first correction for the far less-than-perfect levels of inter-coder reliability that typically characterize hand coding. Applications to sentiment detection about politicians in blog posts. Hopkins, Daniel, and Gary King. 2010.

A Method of Automated Nonparametric Content Analysis for Social Science

, American Journal of Political Science 54, no. 1: 229–247.Abstract
The increasing availability of digitized text presents enormous opportunities for social scientists. Yet hand coding many blogs, speeches, government records, newspapers, or other sources of unstructured text is infeasible. Although computer scientists have methods for automated content analysis, most are optimized to classify individual documents, whereas social scientists instead want generalizations about the population of documents, such as the proportion in a given category. Unfortunately, even a method with a high percent of individual documents correctly classified can be hugely biased when estimating category proportions. By directly optimizing for this social science goal, we develop a method that gives approximately unbiased estimates of category proportions even when the optimal classifier performs poorly. We illustrate with diverse data sets, including the daily expressed opinions of thousands of people about the U.S. presidency. We also make available software that implements our methods and large corpora of text for further analysis. This article led to the formation of Crimson Hexagon
<p><em>You Lie!</em> Patterns of Partisan Taunting in the U.S. Senate (Poster)</p>
Grimmer, Justin, Gary King, and Chiara Superti. 2014.

You Lie! Patterns of Partisan Taunting in the U.S. Senate (Poster)

, in Society for Political Methodology. Athens, GA.Abstract
This is a poster that describes our analysis of "partisan taunting," the explicit, public, and negative attacks on another political party or its members, usually using vitriolic and derogatory language. We first demonstrate that most projects that hand code text in the social sciences optimize with respect to the wrong criterion, resulting in large, unnecessary biases. We show how to fix this problem and then apply it to taunting. We find empirically that, unlike most claims in the press and the literature, taunting is not inexorably increasing; it appears instead to be a rational political strategy, most often used by those least likely to win by traditional means -- ideological extremists, out-party members when the president is unpopular, and minority party members. However, although taunting appears to be individually rational, it is collectively irrational: Constituents may resonate with one cutting taunt by their Senator, but they might not approve if he or she were devoting large amounts of time to this behavior rather than say trying to solve important national problems. We hope to partially rectify this situation by posting public rankings of Senatorial taunting behavior.
Some Statistical Methods for Evaluating Information Extraction Systems
A version of the previous article for a different audience: Lowe, Will, and Gary King. 2003. Some Statistical Methods for Evaluating Information Extraction Systems, Proceedings of the 10th Conference of the European Chapter of the Association for Computational Linguistics: 19-26.Abstract
We present new statistical methods for evaluating information extraction systems. The methods were developed to evaluate a system used by political scientists to extract event information from news leads about international politics. The nature of this data presents two problems for evaluators: 1) the frequency distribution of event types in international event data is strongly skewed, so a random sample of newsleads will typically fail to contain any low frequency events. 2) Manual information extraction necessary to create evaluation sets is costly, and most effort is wasted coding high frequency categories . We present an evaluation scheme that overcomes these problems with considerably less manual effort than traditional methods, and also allows us to interpret an information extraction system as an estimator (in the statistical sense) and to estimate its bias.
Hopkins, Daniel, Gary King, and Ying Lu. System for Estimating a Distribution of Message Content Categories in Source Data. U.S. Patent and Trademark Office. US Patent 8180717, filed 2012.Abstract
A method of computerized content analysis that gives “approximately unbiased and statistically consistent estimates” of a distribution of elements of structured, unstructured, and partially structured source data among a set of categories. In one embodiment, this is done by analyzing a distribution of small set of individually-classified elements in a plurality of categories and then using the information determined from the analysis to extrapolate a distribution in a larger population set. This extrapolation is performed without constraining the distribution of the unlabeled elements to be equal to the distribution of labeled elements, nor constraining a content distribution of content of elements in the labeled set (e.g., a distribution of words used by elements in the labeled set) to be equal to a content distribution of elements in the unlabeled set. Not being constrained in these ways allows the estimation techniques described herein to provide distinct advantages over conventional aggregation techniques.

Software