σ-N天際線：一種新的天際線搜尋類型

σ-N Skyline: A new type of skyline search

天際線查詢問題在近年來引起相當大的關注。給定一個資料集，天際線查詢會回傳那些不被其他點所支配的資料點。在這篇研究中，我們將天際線查詢擴展到σ-neighborhood天際線查詢（σ-N天際線查詢）。相較於過去的天際線查詢，σ-N天際線查詢不僅僅找出天際線點，也會擷取與天際線點競爭的資料點。由於σ-N天際線查詢可以提供更有彈性的答案給使用者，因此應用在策略抉擇、市場分析與商業規劃上都很有幫助。本篇論文定義了一個全新的問題，提出一個新的索引樹與演算法來解決，並透過模擬實驗來展示該演算法之有效性與效率。

The skyline query problem has attracted considerable attention in recent years. Given a dataset, a skyline query returns data points that are not dominated by other points. This study extends the concept of skyline query to a so-called σ-neighborhood skyline query (σ-N skyline query). In contrast to the past skyline query, the σ-N skyline query not only finds the skyline points, but also retrieves points that are competitive with the skyline points. The σ-N skyline query can be useful for applications such as decision making, market analysis, and business planning, as it is able to provide more flexible answers for a user. This paper defines the novel problem, proposes a new index tree and intelligent algorithms to resolve this problem, and conducts a set of simulations to demonstrate the effectiveness and efficiency of the algorithms.