{"title":"Linear Correlation","nodeType":"Other","id":"*0gFnKniNdXkr6DtW","factoryName":"org.knime.base.node.preproc.correlation.compute2.CorrelationCompute2NodeFactory","factoryId":"org.knime.base.node.preproc.correlation.compute2.CorrelationCompute2NodeFactory","path":["Analytics","Statistics"],"owner":"knime","ownerAccountId":"account:team:b5f0848f-496d-4e6a-b869-fa3532248db7","description":"<p>Calculates for each pair of selected columns a correlation coefficient, i.e. a measure of the correlation of the two variables.</p>\n             \n            <p>Which correlation measure is applied depends on the types of the underlying variables:\n <br />\n <tt>numeric &lt;-&gt; numeric</tt>: <a href=\"http://en.wikipedia.org/wiki/Pearson_product-moment_correlation_coefficient\" rel=\"ugc nofollow noopener noreferrer\"> Pearson&#39;s product-moment coefficient</a> . Missing values in a column are ignored in such a way that for the computation of the correlation between two columns only complete records are taken into account. For instance, if there are three columns A, B and C and a row contains a missing value in column A but not in B and C, then the row will be ignored for computing the correlation between (A, B) and (A, C). It will not be ignored for the correlation between (B, C). This corresponds to the function <i>cor(&lt;data.frame&gt;, use&#61;&#34;pairwise.complete.obs&#34;)</i> in the R statistics package.\n <br />\n The value of this measure ranges from -1 (strong negative correlation) to 1 (strong positive correlation). A value of 0 represents no linear correlation (the columns might still be highly dependent on each other, though).\n <br />\n The p-value for these columns indicates the probability of an uncorrelated system producing a correlation at least as extreme, if the mean of the correlation is zero and it follows a t-distribution with <i>df</i> degrees of freedom.\n <br />\n <tt>nominal &lt;-&gt; nominal</tt>: <a href=\"http://en.wikipedia.org/wiki/Pearson%27s_chi-square_test\" rel=\"ugc nofollow noopener noreferrer\"> Pearson&#39;s chi square test on the contingency table</a> . This value is then normalized to a range [0,1] using <a href=\"http://en.wikipedia.org/wiki/Cram%C3%A9r%27s_V\" rel=\"ugc nofollow noopener noreferrer\"> Cramer&#39;s V</a> , whereby 0 represents no correlation and 1 a strong correlation. Missing values in nominal columns are treated such as they were a self-contained possible value. If one of the two columns contains more possible values than specified in the dialog (default 50), the correlation will not be computed.\n <br />\n The p-value for these columns indicates the probability of independent variables showing as extreme level of dependence. The value is the same as for a chi-square test of independence of variables in a contingency table.\n <br />\n Correlation measures for other pairs of columns are not available, they are represented by missing values in the output table and crosses in the accompanying view.</p>\n            \n        \n        ","shortDescription":"Computes correlation coefficients for pairs of numeric or nominal columns.","keywords":["association analysis","pearson correlation","cramer"],"deprecated":false,"streamable":false,"tags":["Analytics","Statistics"],"icon":"data:image/png;base64,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","views":[{"name":"Correlation Matrix","description":"Squared table view showing the pair-wise correlation values of all columns. The color range varies from dark red (strong negative correlation), over white (no correlation) to dark blue (strong positive correlation). If a correlation value for a pair of column is not available, the corresponding cell contains a missing value (shown as cross in the color view)."}],"inPorts":[{"objectClass":"org.knime.core.node.BufferedDataTable","color":"000000","dataType":"Table","optional":false,"name":"Numeric input data","description":"Numeric input data to evaluate"}],"outPorts":[{"objectClass":"org.knime.core.node.BufferedDataTable","color":"000000","dataType":"Table","optional":false,"name":"Correlation measure","description":"Correlation variables, p-values and degrees of freedom."},{"objectClass":"org.knime.core.node.BufferedDataTable","color":"000000","dataType":"Table","optional":false,"name":"Correlation matrix","description":"Correlation variables in a matrix representation."},{"objectClass":"org.knime.base.node.preproc.correlation.pmcc.PMCCPortObjectAndSpec","color":"9b9b9b","dataType":"Correlation","optional":false,"name":"Correlation model","description":"A model containing the correlation measures. This model is appropriate to be read by the Correlation Filter node."}],"dynInPorts":[],"dynOutPorts":[],"additionalSiteInformation":{"url":"https://update.knime.com/analytics-platform/5.12","trusted":true,"enabledByDefault":true,"name":"KNIME Analytics Platform 5.12 Update Site","version":"5.12.0"},"dialog":[{"sectionName":"Options","fields":[{"name":"Column selection","description":"Select the columns to be included in the correlation analysis. Only numeric and nominal columns are available. Use the include/exclude lists to specify which columns should be processed.","optional":false},{"name":"Output column pairs","description":"Select which column pairs of the selected columns should be included in the correlation measure table. If only compatible column pairs are included <tt>numeric &lt;-&gt; nominal</tt> pairs will be excluded. If only pairs with a valid correlation are included all pairs for which the correlation cannot be computed are excluded.","optional":false},{"name":"Possible values count","description":"Select an upper bound for the number of possible values for each of the nominal columns. If more values are encountered in a nominal column, the column will be ignored (no correlation values will be computed).","optional":false},{"name":"p-value","description":"Select which p-value should be computed for Pearson&#39;s product-moment coefficient.\n<ul><li>&#34;two-sided&#34; corresponds to the probability of obtaining a correlation value that is at least as extreme as the observed correlation.</li><li>&#34;one-sided (right)&#34; corresponds to the probability of obtaining a correlation value that shows even greater <b>positive</b> association.</li><li>&#34;one-sided (left)&#34; corresponds to the probability of obtaining a correlation value that shows even greater <b>negative</b> association.</li></ul>\nNote that the p-value for Pearson&#39;s chi square test is always one-sided.\n<ul><li><b>two-sided</b> : Corresponds to the probability of obtaining a correlation value that is at least as extreme as the observed correlation.</li><li><b>one-sided (right)</b> : Corresponds to the probability of obtaining a correlation value that shows even greater <b>positive</b> association.</li><li><b>one-sided (left)</b> : Corresponds to the probability of obtaining a correlation value that shows even greater <b>negative</b> association.</li></ul>","optional":false}]}],"links":[],"kudos":[{"accountId":"account:user:299df9d9-2ae6-400e-8752-869a73beaa8b","user":"raph0007","date":"2020-08-28T08:03:57+00:00"},{"accountId":"account:user:552210dd-3dfc-4b47-bbe6-477d972e6b9e","user":"nilotpalc","date":"2022-05-22T15:19:06+00:00"},{"accountId":"account:user:1836a461-3b13-4757-9a9a-7e7d14ee4422","user":"polli","date":"2024-04-20T18:25:36+00:00"}],"kudosCount":3,"bundleInformation":{"bundleVersion":"5.12.0.v202606261225","bundleName":"KNIME Base Nodes","bundleSymbolicName":"org.knime.base","bundleVendor":"KNIME AG, Zurich, Switzerland","featureSymbolicName":"org.knime.features.base","featureName":"KNIME Base nodes","featureVersion":"5.12.0.v202606261225","featureVendor":"KNIME AG, Zurich, Switzerland","extensionId":"*bjR3r1yWOznPIEXS"},"frequentSuccessors":[]}
