City directories are similar to telephone directories.
If used skillfully, however, they can reveal a great deal more. When the data is regrouped by residences and compared across multiple years, relationships can be spotlighted that are not evident in any single year. If a researcher merely extracted the data for Lafayette D Richey and took no note of other Richeys, then a good clue to kinships would be missed. Although Lafayette is not in the household with Frank and Eliza J Richey in any year, all lived at 3567 Downing in one year or the other. There is surely a connection.