alar-on-function regression<a class="anchor" aria-label="anchor" href="#scalar-on-function-regression"></a>
</h3>
<p>We can build a scalar-on-function linear regression model where the
response variable is a linear function of the multivariate functional
principal components scores. The principal components to retain in the
model can be selected with <code>selection</code> argument. Three
alternatives are available (default is <code>variance</code>):</p>
<ul>
<li>if “variance” (default), the first M mul