The Efficacy of Google's Suggested Keywords and Phrases in Query Expansion Based on "The Least effort Principle" and "Cognitive Load Theory"

Purpose: One of the most effective ways to improve relevance performance in IR systems including Web search engines is to provide their users with tools facilitating query expansion. Search engines such as Google provide users with keyword suggest tools. The aim of this research was to investigate Users reactions regarding the efficacy of Google's suggested keywords/queries in query expansion based on "The Least effort Principle" and "Cognitive load Theory" from users‟ view Design/Methodology/Approach: Through a mixed method approach quantitative and qualitative data were collected from 60 postgraduate students at Ferdowsi University of Mashhad, Iran (Humanities & social Science Basic and engineering science) using four different instruments (questionnaire, thinking aloud technique, query logs, and interviews). Findings: Among others the „relation between suggested keywords and the information need‟ (mean rate of 3.53 out of four) was considered the most important by searchers in selecting suggested keywords for query expansion. Also the „relation between suggested