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12

Ok Ben, here are my assumptions: 1) You've already got your data (I had some address points in a shapefile, and I downloaded census tract and census block shapefiles for Missouri). 2) You've already geocoded your address points and you're comfortable projecting the data. 3) You're comfortable with an OGR/PostGIS solution (both free). Here are some ...


10

You want to assemble a nationwide set in one file? For how many variables? There are a few hoops to get over to actually connect the STFIDs in your shapefile with the data. I couldn't read if your primary problem is decoding the naming schemes of the files and figuring out what is in each, or if it was about relating the primary keys of the shape file and ...


9

It is on the new version of American Factfinder and don't feel bad, even Census Bureau employees are confounded by the new site. Example for population and housing for Newark, DE: Go to http://factfinder2.census.gov Under Topics choose People > Basic Count/Estimate > Population Total and Housing > Basic Count/Estimate > Housing Units Click on Geographies, ...


8

County Level (some states go back to 1776) http://publications.newberry.org/ahcbp/ (in lat/lng) you can use this to attach census data (where available) to the county polygons (you maybe doing this already) But downloaded the GIS Data and there is a wealth of facts on changes etc. with dates and sources. A worthy start. Finding GIS (geocoder. address ...


8

I found this metadata file indicating: C = County I = Interstate M = Common Name O = Other S = State recognized U = U.S.


8

The first step to determining the correct projection of any layer, is to find the projection information, if any, that came with your layer. In the case of a Shapefile, like what you downloaded from Census.gov, that information is contained in a .prj file, short for Projection. Here are the contents of the projection file from the census data: ...


7

You can download Census Blocks from TIGER; you'll just have to download the data on a state-by-state basis and merge it all together. EDIT: See this page for block-level shapefiles that already have the population and housing unit counts attached, so you don't have to deal with joining SF1 tables!


7

Assuming you're using ArcGIS 9.3, get the free Hawth's analysis tools extension for ArcGIS, and use the Zonal Statistics ++ tool. Make sure the shapefile is in the same projection as the raster. From having just looked at the Hawth's tools website for the first time in ages to get the links, I've just seen they're putting all their efforts into developing ...


7

PostgreSQL has a column limit of between 250 and 1600 "depending on column types", and supports spatial data and queries with the PostGIS extension. So I would be inclined to do two things: First, where a column represents a category rather than free text, create a separate table with those categories, and replace the column with an integer ID and foreign ...


7

I recently dealt with the exact same issue with Statistics Canada census profile CSV files containing 2172 columns. You can import your csv into an ESRI File Geodatabase (FGDB) if you have access to ArcGIS. According to ESRI, the FGDB format can handle 65,534 fields in a feature class or table. In my case, I was able to import my 2172 column wide CSV file ...


6

http://www.census.gov/geo/www/tiger/tgrshp2010/tgrshp2010.html allows you to download census blocks by county. Update: the TIGER/shapefiles does not have any demographic data - if that's what you are looking for you would need American FactFinder.


6

I don't know what an STFID is and I have pretty intimate knowledge of the Census counts. The geography file has a record for every geographical unit. There's one for the entire state, for every county, for every tract, for every block etc. Each is uniquely identified by a LOGRECNO. The LOGRECNO will be unique in the geo file. The other files have all of ...


6

UPDATE The new files are now available and known as "Cartographic Boundary Files". More detail on the other types here http://www.census.gov/geo/maps-data/data/tiger.html The County file discussed above is available here: http://www.census.gov/geo/maps-data/data/cbf/cbf_counties.html The official file is not currently available as of 5-12-2011, but ...


6

I don't think I can directly link, but what you want is American Community Survey Table S1810 with New Mexico County Geography. Start here: http://factfinder2.census.gov/faces/nav/jsf/pages/searchresults.xhtml?refresh=t Enter S1810 for your search topic. This should give you four tables named Disability Characteristics. From the options on the left, now ...


6

While some districts may follow block group, tract or even county boundaries, many of them (probably most -- might depend on the individual state) were based on block-level data. Since the districts have to be drawn based on Census data, and since the smallest level of geography the Census Bureau uses is the block, there should be no districts that violate ...


6

Very interesting question! I'd note that the geography area calculation is extremely close (in your last example, 3 msq difference over an area of 20000000 msq. (0.000015%) Since we know that census manages its data inside Oracle Spatial, I'd guess that what you're seeing is a very small difference in the implementation of geodetic area calculation between ...


5

If you want to use Census tracts the good people at Brown University have already done the hard work for you: Brown University Longitudinal Tract Database This resource contains tract-level variables from 1970-2000 interpolated to 2010 boundaries, facilitating longitudinal analysis.


5

The source data is available at http://www.census.gov/geo/maps-data/data/tiger-line.html. Note that the 2000 series tab provides data in the old ASCII format, but you can get the Census tracts by US state for 2000 in shapefile format from a page off the 2010 tab. Other than that, I can only suggest contacting ESRI.


4

Download tiger census block shapefile for your area of interest. Download American Fact Finder demographic tables to join to your block shapefile. Create a point shapefile for your long/lat coordinates. You can then use the Select by Location option to select block features within your buffer distance for each point feature. Summarize selected features by ...


4

For privacy reasons, personally-identifying house-by-house data from the Decennial Census are not available until 72 years after being recorded. Census Blocks are the highest spatial resolution geography for which more recent Decennial Census data are available. If you only want Census Block populations for a couple of counties, use the Census Factfinder. ...


4

I would check that you have downloaded the correct census files. I've spent many wasted days trying to figure out why I could not make an obvious join, only to discover that 2010 census files per state and per county sometimes have different codes. (I know this sounds strange but it is true). Secondly, in the pre-2010 census, you should check how the ...


4

Basically, you can do the extract using ogr2ogr as long as you give the Census tract ID, so it's really an issue of getting 72,000 ogr2ogr calls. ogr2ogr -where "tract = '<tract_id>'" /dest_folder /source_folder block_shapefile -nln block_shapefile_<tract_id> Notes: You don't have to specify the source format, ogr2ogr will figure it out. You ...


4

check this link http://www.geohive.com/cntry/ecuador.aspx for the census data (1990,2001 and 2010) this one http://www.fao.org/geonetwork/srv/en/metadata.show?id=1174&currTab=simple for the admin limits By the way it is better to add the info that you are looking for the admin regions called "Parishes". These are third-level administrative units of ...


4

The Short Answer: No. Census Tracts do change over time (Especially from 2000 to 2010 when in many cases they appear to be essentially redrawn). You can use the faces files to compare the same geographic area with its 2000 Census and 2010 Census assignment using dissolve techniques. You can also check out the relfiles to compare 1990 Census with 2000 Census ...


3

If you need a gridded data set CIESIN's Gridded Population datasets may be of use. See http://sedac.ciesin.columbia.edu/gpw/aboutus.jsp#aboutTable for more details. The best resolution is 30 Arc seconds.


3

I'd recommend using the ACS Summary File Retrieval Tool. It's a macro-enabled Excel workbook that allows for the batch downloading of ACS data for all tracts and block groups within an entire state. This makes it more powerful than the FactFinder website, but it does the downloading of the text files and linking LOGRECNOs for you. Takes less than 30 seconds ...


3

From http://www.census.gov/newsroom/releases/archives/2010_census/cb11-cn151.html, there's a link for the Census Bureau's FTP site. You'll have to know how to decipher the file names to get what you want, but since you're looking for bulk data, I assume you know how to do that. You'll want an FTP client for bulk download. Then you can use your unzipper to ...


3

You don't say if you are using esri or not. ESRI Products come with a "data and maps" dvd. It is not in shp but can be selected and converted to shape using arcmap. I installed mine on a network drive in the mapdata folder. The rest of the path is like this. G:\MapData\ESRI_Data\streetmap_na\data\citylim.sdc


3

I have spent a lot of time mapping block groups and found that rendering them as tiles is usually the most efficient option. Client Side Flash Rendering: Max = Counties The most detailed geography you can reasonably expect a client browser to render on a national scale is US Counties and even those require significant optimization. The NY Times has a ...



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