A survey on the semantics of sequential patterns with negation

TL;DR

This survey investigates how users perceive the semantics of negative sequential patterns, revealing that intuitive understandings differ from those used by current algorithms, impacting interpretability.

Contribution

The paper explores user perceptions of negation semantics in sequential patterns and compares them with algorithmic semantics, highlighting discrepancies and providing recommendations.

Findings

Two semantics are mostly intuitive for users

User perceptions often differ from algorithmic semantics

Recommendations to improve interpretability of pattern semantics

Abstract

A sequential pattern with negation, or negative sequential pattern, takes the form of a sequential pattern for which the negation symbol may be used in front of some of the pattern's itemsets. Intuitively, such a pattern occurs in a sequence if negated itemsets are absent in the sequence. Recent work has shown that different semantics can be attributed to these pattern forms, and that state-of-the-art algorithms do not extract the same sets of patterns. This raises the important question of the interpretability of sequential pattern with negation. In this study, our focus is on exploring how potential users perceive negation in sequential patterns. Our aim is to determine whether specific semantics are more "intuitive" than others and whether these align with the semantics employed by one or more state-of-the-art algorithms. To achieve this, we designed a questionnaire to reveal the semantics' intuition of each user. This article presents both the design of the questionnaire and an in-depth analysis of the 124 responses obtained. The outcomes indicate that two of the semantics are predominantly intuitive; however, neither of them aligns with the semantics of the primary state-of-the-art algorithms. As a result, we provide recommendations to account for this disparity in the conclusions drawn.