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Government Funding Lapse

Because of a lapse in government funding, the information on this website may not be up to date, transactions submitted via the website may not be processed, and the agency may not be able to respond to inquiries until appropriations are enacted. The NIH Clinical Center (the research hospital of NIH) is open. For more details about its operating status, please visit  cc.nih.gov. Updates regarding government operating status and resumption of normal operations can be found at OPM.gov.

An Ecosystem of Health Disparities and Minority Health Resources

Interval Type

Quantile Intervals

The site uses quantile intervals to focus attention on relative rankings - the highest set of areas, the next highest set, and so on to the lowest set. With quantile intervals, the same number of areas is assigned to each group. If the number of intervals is set to four, then the groups are quartiles, five intervals are quintiles, etc. With quantile maps, outlier values are less visible since they are grouped with other high or low value areas.

Additional information about interval types

There is no single best interval type (also known as a classification method). For additional details, see: https://www.cdc.gov/brfss/gis/gis_maps_faq.htmExternal Web Site Policy and this journal article: Brewer, C. A. and L. Pickle, 2002. Evaluation of Methods for Classifying Epidemiological Data on Choropleth Maps in Series. Annals of the Association of American Geographers, Vol. 92, No. 4, pp. 662-681.

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