Rodger's method

<p>Rodger's method is a <a href="/facts/Statistics/DNPsKGYU">statistical procedure</a> for examining research data <a href="/facts/Post_hoc_analysis/mCNhrGls">post hoc</a> following an 'omnibus' analysis (e.g., after an <a href="/facts/Analysis_of_variance/HHR2jkDk">analysis of variance</a> – anova).  The various components of this methodology were fully worked out by R. S. Rodger in the 1960s and 70s, and seven of his articles about it were published in the British Journal of Mathematical and Statistical Psychology between 1967 and 1978.
</p><p>Statistical procedures for finding differences between groups, along with interactions between the groups that were included in an experiment or study, can be classified along two dimensions: 1) were the statistical contrasts that will be evaluated decided upon prior to collecting the data (planned) or while trying to figure out what those data are trying to reveal (<i>post hoc</i>), and 2) does the procedure use a decision-based (i.e., per contrast) error rate or does it instead use an experiment-wise error rate.  Rodger's method, and some others, are classified according to these dimensions in the table below.
</p>
Table 1: Some multiple comparison procedures<table><tbody><tr><th></th><th>Planned contrasts</th><th>Post hoc contrasts</th></tr><tr><th>Decision-based error rate</th><td><i>t</i> tests</td><td>Duncan's method  Rodger's method</td></tr><tr><th>Experiment-wise error rate</th><td>Bonferroni's inequality  Dunnett's method</td><td>Newman–Keuls method  Tukey's range method  Scheffé's method</td></tr></tbody></table>

Rodger's method open-in-new

Rodger's method