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<front>
<journal-meta>
<journal-id journal-id-type="publisher-id">JDS</journal-id>
<journal-title-group><journal-title>Journal of Data Science</journal-title></journal-title-group>
<issn pub-type="epub">1683-8602</issn><issn pub-type="ppub">1680-743X</issn><issn-l>1680-743X</issn-l>
<publisher>
<publisher-name>School of Statistics, Renmin University of China</publisher-name>
</publisher>
</journal-meta>
<article-meta>
<article-id pub-id-type="publisher-id">JDS1158</article-id>
<article-id pub-id-type="doi">10.6339/24-JDS1158</article-id>
<article-categories><subj-group subj-group-type="heading">
<subject>Statistical Data Science</subject></subj-group></article-categories>
<title-group>
<article-title>SPA: Signflip Parallel Analysis to Optimize the Number of Principal Components in Two-dimensional PCA</article-title>
</title-group>
<contrib-group>
<contrib contrib-type="author">
<contrib-id contrib-id-type="orcid">https://orcid.org/0000-0002-8222-810X</contrib-id>
<name><surname>Li</surname><given-names>Zhaoyuan</given-names></name><email xlink:href="mailto:lizhaoyuan@cuhk.edu.cn">lizhaoyuan@cuhk.edu.cn</email><xref ref-type="aff" rid="j_jds1158_aff_001">1</xref>
</contrib>
<contrib contrib-type="author">
<name><surname>Kuang</surname><given-names>Yiling</given-names></name><xref ref-type="aff" rid="j_jds1158_aff_002">2</xref>
</contrib>
<aff id="j_jds1158_aff_001"><label>1</label><institution>The Chinese University of Hong Kong, Shenzhen</institution>, <country>China</country></aff>
<aff id="j_jds1158_aff_002"><label>2</label><institution>The Chinese University of Hong Kong</institution>, <country>China</country></aff>
</contrib-group>
<author-notes>
<corresp id="cor1"><label>∗</label>Corresponding author. Email: <ext-link ext-link-type="uri" xlink:href="mailto:lizhaoyuan@cuhk.edu.cn">lizhaoyuan@cuhk.edu.cn</ext-link>.</corresp>
</author-notes>
<pub-date pub-type="ppub"><year>2024</year></pub-date><pub-date pub-type="epub"><day>22</day><month>11</month><year>2024</year></pub-date><volume content-type="ahead-of-print">0</volume><issue>0</issue><fpage>1</fpage><lpage>18</lpage><supplementary-material id="S1" content-type="archive" xlink:href="jds1158_s001.zip" mimetype="application" mime-subtype="x-zip-compressed">
<caption>
<title>Supplementary Material</title>
<p>The supplementary material contains a zipped folder, which contains codes and three data sets for reproducing all results. Please go to <uri>https://figshare.com/s/824176b60a12b8ee0535</uri>.</p>
</caption>
</supplementary-material><history><date date-type="received"><day>23</day><month>7</month><year>2024</year></date><date date-type="accepted"><day>20</day><month>10</month><year>2024</year></date></history>
<permissions><copyright-statement>2024 The Author(s). Published by the School of Statistics and the Center for Applied Statistics, Renmin University of China.</copyright-statement><copyright-year>2024</copyright-year>
<license license-type="open-access" xlink:href="https://creativecommons.org/licenses/by/4.0/">
<license-p>Open access article under the <ext-link ext-link-type="uri" xlink:href="https://creativecommons.org/licenses/by/4.0/">CC BY</ext-link> license.</license-p></license></permissions>
<abstract>
<p><xref ref-type="bibr" rid="j_jds1158_ref_022">Yang et al.</xref> (<xref ref-type="bibr" rid="j_jds1158_ref_022">2004</xref>) developed the two-dimensional principal component analysis (2DPCA) for image representation and recognition, widely used in different fields, including face recognition, biometrics recognition, cancer diagnosis, tumor classification, and others. 2DPCA has been proven to perform better and computationally more efficiently than traditional principal component analysis (PCA). However, some theoretical properties of 2DPCA are still unknown, including determining the number of principal components (PCs) in the training set, which is the critical step in applying 2DPCA. Without rigorous criteria for determining the number of PCs hampers the generalization of the application of 2DPCA. Given this issue, we propose a new method based on parallel analysis to determine the number of PCs in 2DPCA with statistical justification. Several image classification experiments demonstrate that the proposed method compares favourably to other state-of-the-art approaches regarding recognition accuracy and storage requirement, with a low computational cost.</p>
</abstract>
<kwd-group>
<label>Keywords</label>
<kwd>2DPCA</kwd>
<kwd>feature extraction</kwd>
<kwd>image analysis</kwd>
</kwd-group>
<funding-group><funding-statement>Zhaoyuan Li’s research is partially supported by National Natural Science Foundation of China (No. 11901492) and Shenzhen Science and Technology Program (ZDSYS 20211021111415025).</funding-statement></funding-group>
</article-meta>
</front>
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