I'm trying to cut census block data to a study area. I have a study area polygon (made from selecting whole counties of interest) and clipped the census data by this. When I visited the new Census file I found this process has created "slivers" from the original census dataset that are very small (area is less than a mile) but its population is in the thousands; the entire population of the original block has been cramped into this tiny area. I had thought clipping the data by the study are would've been successful since block groups, at least to my knowledge, do not cross counties. Is there any way to easily remove these extraneous slivers or a better way to cut the census data to a study area?
The problem is probably that your County boundaries and your Census blocks are not identical and don't line up right leaving you with slivers. Instead of clipping, You could just query out the Counties you would like to use, within the study area, using the "COUNTYCU" field in the attribute table. This field gives a unique identifier to each County. Using this identifier would ensure that you are using blocks that are within your study area only.