Natural language why-question in Business Intelligence applications: model and recommendation approach

Business Intelligence is the key technology for users to effectively extract valuable information from oceans of data for decision-making. Data warehouses and on-line analytical processing systems have therefore been developed to contribute effectively to the decision-making process. To extract information that is useful to decision-making, decision-makers express their needs in natural language. Such requirements may be formulated in natural language interfaces in free syntax, avoiding unfamiliar language (SQL, MDX). Natural Language queries can stand for WH-questions (“What, Who, Where, Why, etc.”) or a set of Keywords. In this paper, we emphasize on the “Why-Question”. This type of question provides answers that help in the diagnosis analysis of the data Warehouse. To deal with a Why-Question, we propose a model that mainly captures the components that reflect the multidimensional aspect of the Data Warehouse. When a decision-maker formulates his Why-Question in natural language, he uses his own terms. This decisional need can be not precise because the decision-maker is not always aware of the Data Warehouse’s lexicon as well as the Why-Question’s model. Consequently, the decision-maker must reformulate his initial question. Otherwise, the Why-Question’s answering process will not be triggered. This situation is not obvious for a decision-maker, especially when the reformulation of the question becomes iterative. To handle these issues, we lean towards a Why-Question’s recommendation approach based on both the Data Warehouse’s content and the decision maker’s requirement. This proposal aims to recommend to the decision-maker a set of natural language Why-Questions instead of rephrasing his initial question. To guide the recommendation process, we rely on a grammar that formalizes the Why-Question’s model. To validate our approach, a tool called “WQ-Recommender” is developed. An experimental study is presented to evaluate the relevance of the proposal.