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Annotating Opinions in the World Press. Theresa Wilson and Janyce Wiebe University of Pittsburgh Intelligent Systems Program and Department of Computer Science. Introduction. Private State : mental or emotional state, which cannot be directly observed or verified (Quirk et al., 1985).
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Annotating Opinions in the World Press Theresa Wilson and Janyce Wiebe University of Pittsburgh Intelligent Systems Program and Department of Computer Science
Introduction Private State: mental or emotional state, which cannot be directly observed or verified (Quirk et al., 1985) Speculation Emotions Beliefs Opinions Evaluations SIGdial 2003
Private States in Text Subjectivity: aspects of language used to express private states, including opinions, emotions, evaluations, speculations, sentiments (Banfield 1982) “Complained” “You Idiot!” “Terrible product” “Enthused” “Wonderful!” “Great idea” “Speculated” “Maybe” “I wonder” (See Fodor 1979, Cohn 1978, Chafe 1986, Fludernik 1993, Wiebe 1994, Stein & Wright 1995 for additional references.) SIGdial 2003
Why do we care? • News articles mix of factual/subjective language • Help existing NLP applications: IE, IR, summarization systems, etc. • Support new tasks: multi-perspective question answering SIGdial 2003
Two Main Ways of Expressing Private States • Direct mentions of private states The United States fears a spill-over from the anti-terrorist campaign. • Expressive subjective elements The part of the US human rights report about China is full of absurdities and fabrications. SIGdial 2003
Private States and Speech Events • Speech Event speaking or writing “We foresaw electoral fraud but not daylight robbery,” Tsvangirai said. Medical Department head Dr. Hameed Saeed said the patient’s blood has been sent to the Institute for Virology in Johannesburg for analysis. SIGdial 2003
(writer) (writer, Xirao-Nima, US) (writer, Xirao-Nima) “The US fears a spill-over’’, said Xirao-Nima, a professor of foreign affairs at the Central University for Nationalities. (writer) (writer, Xirao-Nima) (writer, Xirao-Nima) “The report is full of absurdities,’’ he continued. Nested Sources SIGdial 2003
Annotation Scheme • Implemented in GATE (http://gate.ac.uk) Shorthand for direct private state or speech event expression SIGdial 2003
On (Direct Private State or Speech Event) nested-source onlyfactive overall-strength on-strength attitude-type attitude-toward is-implicit minor Expressive Subjective Element nested-source strength attitude-type Attributes for Annotation Types SIGdial 2003
On (Direct Private State or Speech Event) nested-source onlyfactive overall-strength on-strength attitude-type attitude-toward is-implicit minor Expressive Subjective Element nested-source strength attitude-type Attributes for Annotation Types SIGdial 2003
On (Direct Private State or Speech Event) nested-source onlyfactive overall-strength on-strength attitude-type attitude-toward is-implicit minor Expressive Subjective Element nested-source strength attitude-type Attributes for Annotation Types SIGdial 2003
On (Direct Private State or Speech Event) nested-source onlyfactive overall-strength on-strength attitude-type attitude-toward is-implicit minor Expressive Subjective Element nested-source strength attitude-type Attributes for Annotation Types SIGdial 2003
(writer, Xirao-Nima, US) onlyfactive=no (writer, Xirao-Nima) onlyfactive=yes (writer) onlyfactive=yes “The US fears a spill-over’’, said Xirao-Nima, a professor of foreign affairs at the Central University for Nationalities. onlyfactive Attribute SIGdial 2003
Important! onlyfactive=no may still contain facts “John criticized Mary for smoking.” (writer, John) onlyfactive=no SIGdial 2003
on-strength=neutral The Foreign Ministry said . . . on-strength=medium The Foreign Ministry objected . . . The Foreign Ministry vehemently denied . . . . . . inaccurate section on Chechnya. strength=low . . . odious section on Chechnya. strength=high Strength of Private State on-strength=high SIGdial 2003
overall-strength=high on-strength=medium strength=high The Foreign Ministry objected in particular to the “odious” section on Chechnya. strength=medium strength=medium “We foresaw electoral fraud but not daylight robbery,” Tsvangirai said. on-strength=neutral overall-strength=medium Overall Strength of Private State SIGdial 2003
Data • English-language versions of articles from world press (FBIS + few other sources) • 8500 sentences have been annotated • Agreement Study • 3 annotators (A, M, S) • 210 sentences (13 documents) • 1/3 news, 1/3 news on “hot-topic”, 1/3 editorials SIGdial 2003
Types of Agreement • Agreement for spans • Ons • Expressive Subjective Elements • Agreement for ON onlyfactive attribute • Agreement for sentences • Derive sentence-level annotations from lower-level annotations SIGdial 2003
A: His comments were immediately contested . . . M: His comments were immediately contested . . . Agreement Issues: Spans • Overlapping spans ok it’s a match SIGdial 2003
(writer, Russian Miliatary) A: Russian military policy has been to keep a distance from . . . M: Russian military policy has been to keep a distance from . . . (writer, Russian Miliatary) Agreement Issues: Spans • Different set of annotations for each annotator Kappa inappropriate SIGdial 2003
|A matching B| |A| Agreement Evaluation: spans • Agreement measured by percentage of A’s constituents matching B’s, and vice versa agr (a||b) = SIGdial 2003
Span Agreement: Ons SIGdial 2003
A:Reformers told Putin all along that he should take advantage of "the rare opportunity for (Russia) to become integrated with the civilized world." But main stream Russian military policy has been to keep a distance from America. M:Reformers told Putin all along that he should take advantage of "the rare opportunity for (Russia) to become integrated with the civilized world.“ But main stream Russian military policy has been to keep a distance from America. writer on Measuring Agreement: ON onlyfactive SIGdial 2003
A:Reformers told Putin all along that he should take advantage of "the rare opportunity for (Russia) to become integrated with the civilized world." But main stream Russian military policy has been to keep a distance from America. M:Reformers told Putin all along that he should take advantage of "the rare opportunity for (Russia) to become integrated with the civilized world.“ But main stream Russian military policy has been to keep a distance from America. writer on Measuring Agreement: ON onlyfactive SIGdial 2003
A: Reformers told Putin all along that he should take advantage of "the rare opportunity for (Russia) to become integrated with the civilized world." But main stream Russian military policy has been to keep a distance from America. M: Reformers told Putin all along that he should take advantage of "the rare opportunity for (Russia) to become integrated with the civilized world.“ But main stream Russian military policy has been to keep a distance from America. writer on Measuring Agreement: ON onlyfactive onlyfactive=yes onlyfactive=no onlyfactive=yes onlyfactive=no onlyfactive=no onlyfactive=yes SIGdial 2003
Agreement results: onlyfactive Ave Kappa Borderlineonlyfactive: • At least one annotator marked expression onlyfactive=no • Neither annotator marked expression overall-strength > low SIGdial 2003
(writer) onlyfactive=yes (writer, Sue) onlyfactive=no Subjective Sue said, “The election was fair.” (writer) onlyfactive=yes (writer, Sue) onlyfactive=yes Objective Sue said, “The election was Tuesday.” Deriving Sentence-level Annotations SIGdial 2003
Agreement results: sentence-level subjective annotations Ave Kappa Borderline subjective sentence: • At least one annotator marked at least one expression onlyfactive=no • Neither annotator marked an overallstrength > low SIGdial 2003
Conclusions • Detailed scheme for annotation of opinions and other private states • Good agreement between annotators • Strong agreement about clear cases of subjectivity • Lower-level annotations higher-level subjective sentence annotations • Extendable SIGdial 2003
Using GATE to perform private state annotations • GATE http://gate.ac.uk • General annotation instructions and GATE instructions http://www.cs.pitt.edu/~wiebe/pubs/ardasummer02 SIGdial 2003
Thank you This work was performed in support of the Northeast Regional Research Center (NRRC) which is sponsored by the Advanced Research and Development Activity in Information Technology (ARDA), a U.S. Government entity which sponsors and promotes research of import to the Intelligence Community which includes but is not limited to the CIA, DIA, NSA, NIMA and NRO. SIGdial 2003
Contingency Table: onlyfactive judgements Agreement for onlyfactive judgments, borderline cases removed Agreement for onlyfactive judgments SIGdial 2003
Onlyfactive Agreement SIGdial 2003
Subjective Sentence Agreement SIGdial 2003
Why we exclude minor on annotations This is the first time that the Cuban government has expressed its position over the U.S. holding of the Taliban and al-Qaeda prisoners in its territory. (writer, Cuban gov) onlyfactive=no Objective Sentence! SIGdial 2003