"Groupitizing": a strategy for numerosity estimation

<p>Each file contains a matrix called &ldquo;matr&rdquo;. Each row of the matrix &ldquo;matr&rdquo; is a trial.&nbsp;</p> <p>The columns contain the following information:</p> <ol> <li>subject response</li> <li>the presented numerosity</li> <li>subject response&nbsp;</li> <li>zeros</li> <li>stimulus duration</li> <li>Response time</li> <li>Grouped (1) or random (2) presentation&nbsp;</li> <li>1</li> <li>1</li> <li>Number of items of the upper-left quadrant</li> <li>Number of items of the lower-left quadrant</li> <li>Number of items of the upper-right quadrant</li> <li>Number of items of the lower - right quadrant</li> </ol>