A method used to make a generalized map from observed data and used to highlight the main features and important trends of a geographic distribution. Archaeological observations mapped are discontinuous and at isolated points and therefore must be used to give information over a wider area. This is done either by averaging the values at a number of points to produce a general value or by a form of linear regression analysis which finds the contours which best fit the observations plotted on the map. The map produced then shows a general trend of the distribution, along with localized fluctuations. The technique is most useful for displaying archaeological data in a simplified and generalized form, making it easier to examine and explain the broad regional trends and the local variations. It can be applied to several different artifact distributions at the regional level, and has also been used to describe the distribution of artifact types within a site.