Although we realize that the following are not readily available, in the future it would also be useful to have, for both the current census processes and, to the extent possible, any alternative approaches: (1) estimates of census costs by component operation (and the recent history of costs)1 and (2) the potential impact on the quality of the collected data by component operation. The attribution of both coverage and characteristics error, to component operations or current processes, let alone suggested alternatives, on a national level, not to mention for demographic subgroups, would have been very difficult to achieve in past censuses. The planned census coverage measurement program in 2010 is hoping to make progress in assessing and attributing component coverage error to various sources. This is an important development because the Census Bureau could better justify priorities in undertaking various experiments by providing information on the impact on costs and quality of various alternatives. Furthermore, even if estimates of costs and impacts on accuracy are difficult to estimate, it should generally be possible to determine the major cost drivers and the leading sources of error.
There are two other modifications to the Census Bureau’s list of topics that would have facilitated setting priorities. First, it would have been helpful if the list had been separated into candidates for evaluations and candidates for formal experiments. An experiment is, generally speaking, not possible until a reasonable alternative has been identified. Therefore, the listing of any alternative methodologies along with any knowledge of their potential advantages and disadvantages will facilitate the discussion of which issues should be focused on for either experimentation or evaluation. Second, a summary of the current state of research on some of the issues described would have been helpful (in Appendix A, the column on “new to census” is related to this). While some of these issues are extremely new, some, for example questionnaire design, are topics for which the Census Bureau has a history of relevant research. This information would have supported a more refined judgment of the likelihood that use of various alternative approaches might lead to important improvements.
So, without an overall strategy for the design of the 2020 census, it was difficult for the panel to develop strict priorities for the topics that should and should not be examined through the use of experiments in the 2010 census. T his lack of a strategy could have been overcome to some degree with information on the potential impact on census costs and accuracy of replacing various census component processes with alternative processes. This is so because the overall goal of research on census methods has at its most basic level two main objectives: reducing costs and improving accuracy. However, this information is not available at this point and so the panel developed the following set of priority topics for experiments based on speculations concerning the possible designs of the 2020 census and qualitative information on the potential impact on costs and