Geodemographic data resources.

Geodemographic analysis uses social and economic data about local neighborhoods derived principally from secondary information sources. These data are called secondary because, essentially, they are 'second hand', gathered by entities such as government agencies rather than by the geodemographic researcher. In many cases, the purpose for collecting such data is legislated or the data are necessary for a governmental administrative procedure and their ultimate applications are quite different than those of a marketer to consumers or other businesses. Often secondary data are transactional rather than subjective -- i.e., they document actions (such as the registration of a birth) rather than solicit replies to verbal inquiries (such as "how much was your salary last year?").

Primary data, on the other hand, are structured by the researcher for the purpose of conducting experimental ad hoc research (research focussed on a narrow and specific objective).  Such structuring depends on the researcher's knowledge, intuition and experience for its validity. Validity in this context refers to the capacity of a measurement device, such as a questionnaire item, to measure what the experimenter intends it to measure, without prior bias or verbal misunderstanding.

Since collection of primary data is ever more expensive and respondents ever more difficult to recruit, samples tend to be quite small and sometimes fail to be properly representative of the population in general.  While many well designed, adequately representative and validly measured primary surveys are completed, their use in directing marketing actions at a small geographic level is limited or impossible since their small sample sizes render them incapable of generating statistically significant results for specific areas.  The smallest areas for which national survey respondents can be tabulated hold about 100,000 persons. These are the Public Use Microdata Areas of the United States Census of Population and Housing (PUMAS).  This data source will be discussed in more detail below.

More about geodemographic data resources...