%0 Journal Article
	%A Youngji Yoo and  Cheong-Sool Park and  Jun Seok Kim and  Young-Hak Lee and  Sung-Shick Kim and  Jun-Geol Baek
	%D 2012
	%J International Journal of Computer and Information Engineering
	%B World Academy of Science, Engineering and Technology
	%I Open Science Index 72, 2012
	%T Clustering Mixed Data Using Non-normal Regression Tree for Process Monitoring
	%U https://publications.waset.org/pdf/978
	%V 72
	%X In the semiconductor manufacturing process, large
amounts of data are collected from various sensors of multiple
facilities. The collected data from sensors have several different characteristics
due to variables such as types of products, former processes
and recipes. In general, Statistical Quality Control (SQC) methods
assume the normality of the data to detect out-of-control states of
processes. Although the collected data have different characteristics,
using the data as inputs of SQC will increase variations of data,
require wide control limits, and decrease performance to detect outof-
control. Therefore, it is necessary to separate similar data groups
from mixed data for more accurate process control. In the paper,
we propose a regression tree using split algorithm based on Pearson
distribution to handle non-normal distribution in parametric method.
The regression tree finds similar properties of data from different
variables. The experiments using real semiconductor manufacturing
process data show improved performance in fault detecting ability.
	%P 1699 - 1703