A model that assumes things will behave as they have in the past. In time series, the naive model extends the latest observation (see <a href="search.pl?p=random walk model">random walk model</a>). For <a href="search.pl?p=cross-sectional data">cross-sectional data</a>, the <a href="search.pl?p=base rate">base rate</a> can serve as a naive model. <o:p></o:p></P>