id="value">Value<a class="anchor" aria-label="anchor" href="#value"></a></h2>
    <p>Data frame.</p>
    </div>
    <div class="section level2">
    <h2 id="author">Author<a class="anchor" aria-label="anchor" href="#author"></a></h2>
    <p>Juan Alberto Molina-Valero,
  María José Ginzo Villamayor,
  Manuel Antonio Novo Pérez,
  Adela Martínez-Calvo,
  Juan Gabriel Álvarez-González,
  Fernando Montes and
  César Pérez-Cruzado.</p>
    </div>

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