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<p>Dear developers,<br>
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<p>I tired to reproduce the confidence intervals for the Log Ratio for the keywords function in
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<p>CQPweb 3.1.16 myself (in R) and failed. Subsequently, when trying to figure out the formula that is used from the source code (3.2.11), I found the following line in the file "lib/keywords.inc.php":<br>
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<p>$fragment_CIhalf = "($Z_unit * SQRT( ($O12 / ($R1 * IF($O11 > 0, $O11, 0.5))) + ($O22 / ($R2 * IF($O11 > 0, $O11, 0.5))) ))";<br>
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<p>shouldn't that be: </p>
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<p>$fragment_CIhalf = "($Z_unit * SQRT( ($O12 / ($R1 * IF($O11 > 0, $O11, 0.5))) + ($O22 / ($R2 * IF($O21 > 0, $O21, 0.5))) ))";</p>
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<p>I guess the second IF($O11 > 0, $O11, 0.5) is a copy-paste error and should really be IF($O21 > 0, $O21, 0.5) as the proportion of "word" in the second corpus should be used. The source code is version 3.2.11, but the code is consistent with the results
displayed by 3.1.16. </p>
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<p>Best,</p>
<p>Thoralf</p>
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