Anchoring and Agreement in Syntactic Annotations

TL;DR

This paper investigates how cognitive bias, specifically anchoring, affects human syntactic annotations, leading to overestimated parser performance and lower annotation quality, with implications for future annotation and evaluation strategies.

Contribution

It provides empirical evidence of anchoring effects in syntactic annotation and offers systematic agreement estimates that match state-of-the-art parser performance.

Findings

Anchoring influences syntactic annotation quality.

Anchoring causes overestimation of parser performance.

Agreement levels are comparable to top parser results.

Abstract

We present a study on two key characteristics of human syntactic annotations: anchoring and agreement. Anchoring is a well known cognitive bias in human decision making, where judgments are drawn towards pre-existing values. We study the influence of anchoring on a standard approach to creation of syntactic resources where syntactic annotations are obtained via human editing of tagger and parser output. Our experiments demonstrate a clear anchoring effect and reveal unwanted consequences, including overestimation of parsing performance and lower quality of annotations in comparison with human-based annotations. Using sentences from the Penn Treebank WSJ, we also report systematically obtained inter-annotator agreement estimates for English dependency parsing. Our agreement results control for parser bias, and are consequential in that they are on par with state of the art parsing performance for English newswire. We discuss the impact of our findings on strategies for future annotation efforts and parser evaluations.