Tham khảo tài liệu 'business process improvement_12', kỹ thuật - công nghệ, điện - điện tử phục vụ nhu cầu học tập, nghiên cứu và làm việc hiệu quả | . Dex scatter plot Motivation The scatter plot is the primary data analysis tool for determining if and how a response relates to another factor. Determining if such a relationship exists is a necessary first step in converting statistical association to possible engineering cause-and-effect. Looking at how the raw data change as a function of the different levels of a factor is a fundamental step which it may be argued should never be skipped in any data analysis. From such a foundational plot the analyst invariably extracts information dealing with location shifts variation shifts and outliers. Such information may easily be washed out by other more advanced quantitative or graphical procedures even computing and plotting means . Hence there is motivation for the dex scatter plot. If we were interested in assessing the importance of a single factor and since important by default means shift in location then the simple scatter plot is an ideal tool. A large shift with little data overlap in the body of the data from the - setting to the setting of a given factor would imply that the factor is important. A small shift with much overlap would imply the factor is not important. The dex scatter plot is actually a sequence of k such scatter plots with one scatter plot for each factor. Plot for defective springs data The dex scatter plot for the defective springs data set is as follows. http div898 handbook pri section5 2 of 4 5 1 2006 10 31 23 AM . Dex scatter plot How to interpret As discussed previously the dex scatter plot is used to look for the following 1. Most Important Factors 2. Best Settings of the Most Important Factors 3. Outliers. Each of these will be discussed in turn. Most Important Factors For each of the k factors as we go from the - setting to the setting within the factor is there a location shift in the body of the data If yes then 1. Which factor has the biggest such data location shift that is has least .
