<p>You needn't pick out which functions to use from the <code>car</code> or <code>effects</code> packages. Examples of how to apply statistical methods, using any software (even if not specifically requested by the OP), can certainly be useful, but their provision isn't a necessary condition for a good answer.</p>

<p>Nevertheless, merely name-checking something the OP ought to look into makes for a rather meagre answer, which would typically benefit from a brief explanation of at least </p>

<ul>
<li><p>how it relates to the question</p></li>
<li><p>what exactly it is (perhaps by giving a reference)</p></li>
</ul>

<p>There's often some ambiguity in questions &amp; answers (what <em>is</em> a "net effect" anyway? which of added variable &amp; component-plus-residual plots shows it? are either of those the same as partial-regression plots?), resolving which gives readers confidence that they're not going to be sent off on a wild-goose chase, &amp; doesn't amount to hand-holding.</p>

<p>All in my opinion, of course.</p>
