英文随筆(part1)

随筆，練練自己英文寫作

翻譯自：《資料聚類》-- 張憲超

Unsupervised Learning

The core of Artificial Intelligence is machine learning(ML), whose main task is to identify and distinguish between things. ML is divided into two categories supervised learning and unsupervised learning. The main task of supervised learning is classification, i.e., to complete the distinction of new data with a large number of labeled data. The main task of unsupervised learning is clustering, i.e., to distinct data into many class without manual intervention.

Humanity must be clear aware of that the unsupervised learning is more difficult than supervised learning and there are far fewer researchers in unsupervised than in supervised. Thus, the process of unsupervised development is relatively slow. Nevertheless, the field of unsupervised learning has been explored by scholars for decades. Many research results such as the k-means algorithm were studied. Especially in recent years, with the importance of unsupervised learning has been recognized, more scholars have devoted themselves into this filed and have achieved breakthrough.

Clustering is one of the most important issue in the domain of unsupervised learning. Clustering is employed in many real-world problem, such as image segmentation, bioinformation and finance fraud. Clustering is able to group data which have no label, thus discovering the natural structure of data. Clustering always be apply in three areas as follow.

1. find latent structure of data
2. group data naturally
3. compressed data

1. technology-centered research
2. data-centered research
3. clustering-derived-centered research