کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8038018 1518319 2016 16 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Why Principal Component Analysis of STEM spectrum-images results in “abstract”, uninterpretable loadings?
موضوعات مرتبط
مهندسی و علوم پایه مهندسی مواد فناوری نانو (نانو تکنولوژی)
پیش نمایش صفحه اول مقاله
Why Principal Component Analysis of STEM spectrum-images results in “abstract”, uninterpretable loadings?
چکیده انگلیسی
Principal Component Analysis (PCA) can improve dramatically the treatment of large STEM spectrum-images by finding the directions (loadings) of highest data variance in the factor space and projecting the data on these directions. Loadings typically do not show clear physical meanings, thus the interpretation of PCA results is difficult. This work investigates the potential reasons for appearing such counterintuitive PCA outputs. The following reasons are identified: (i) missing the step of centering the data in the PCA pre-treatment, (ii) complexity of data variations inconsistent with the orthogonality restrictions of PCA, (iii) non-linearity caused either by chemical variations or by the peculiarities of the spectra formation, and (iv) inaccuracy in extracting major PCA components. In many cases, the PCA treatment can be altered in such a way that the intuitively clear loadings are delivered.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Ultramicroscopy - Volume 160, January 2016, Pages 197-212
نویسندگان
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