Dexter, Thanks so much for your reply. I wasn't aware of the two sources you cite, and I'll be sure to include them in my work.
The open Baltimore website, at https://data.baltimorecity.gov/datasets/neighborhood-1/explore, has statistics for my neighborhood, Radnor-Winston (https://radnorwinston.org).The Baltimore Neighborhood Indicators Alliance at https://bniajfi.org/vital_signs/ lumps us into North Baltimore/Guilford/Homeland, which, as I'm sure you're aware, contains many homes (mansions!) with very different characteristics than the people of Radnor-Winston. Thanks, again, for your help and expertise. I learned a lot from your note. -Kevin On 8/7/23 15:43, Dexter Locke wrote: > Hi Kevin and all, > > Given the binned data, you could count the number of people per age > class for those 10 blocks. You can then express that in a number of > different ways, like percent under 25 years old, or by calculating the > dependency ratio > <https://www.who.int/data/gho/indicator-metadata-registry/imr-details/1119#:~:text=Definition%3A,a%20specific%20point%20in%20time.>. > > I do think it is feasible to calculate an estimated mean from the counts > within groups representing ranges. See, for example, here: > https://stackoverflow.com/questions/18887382/how-to-calculate-the-median-on-grouped-dataset > > <https://stackoverflow.com/questions/18887382/how-to-calculate-the-median-on-grouped-dataset> > > Since you are working in Baltimore, you may consider looking at The > Baltimore Neighborhood Indicators Alliance > https://bniajfi.org/vital_signs/ <https://bniajfi.org/vital_signs/>. > They provide useful data on a range of issues (transportation, crime, > education, environment etc.) including summaries from Census-derived > demographics. What you are seeking may already exist. BNIA creates > neighborhoods or "community statistical areas" (n=55) based on > aggregates of Census data. > > Although not pertaining to age, Baltimore City Planning has paid Census > in the past to aggregate from individual-level Census data to the more > colloquially-used definitions of Baltimore shown here (n = 273): > https://data.baltimorecity.gov/datasets/neighborhood-1/explore?location=39.284832%2C-76.620516%2C12.91 > > <https://data.baltimorecity.gov/datasets/neighborhood-1/explore?location=39.284832%2C-76.620516%2C12.91> > > Best, Dexter > https://dexterlocke.com/ <https://dexterlocke.com/> > > > > > > On Mon, Aug 7, 2023 at 3:02 PM Kevin Zembower via R-sig-Geo > <r-sig-geo@r-project.org <mailto:r-sig-geo@r-project.org>> wrote: > > Josiah, thanks for your reply. > > Regarding my objective, I'm trying to compile census statistics for the > blocks that make up the neighborhood where I live. It consists of ten > census blocks, of which I selected three for simplicity in my example. > The census block-group which contains these ten blocks also contains > some blocks which are outside of my neighborhood and shouldn't be > counted or included. > > Since I won't be able to calculate the median age from the age and > count > data, and since the individual data doesn't seem to be available, is it > your thought that I can't produce a valid median age for a group of > census blocks? > > Thanks so much for your advice. > > -Kevin > > On 8/7/23 14:38, Josiah Parry wrote: > > Hey Kevin, I don't think you're going to be able to get > individual level > > data from the US Census Bureau. The closest you may be able to > get is > > the current population survey (CPS) which I believe is also > available > > via tidycensus. Regarding your first question, I'm not sure I follow > > what your objective is with it. I would use a geography of census > block > > groups as the measure of median for census block groups. > Otherwise it is > > unclear how you are defining what a "group of blocks" is. > > > > On Mon, Aug 7, 2023 at 2:34 PM Kevin Zembower via R-sig-Geo > > <r-sig-geo@r-project.org <mailto:r-sig-geo@r-project.org> > <mailto:r-sig-geo@r-project.org <mailto:r-sig-geo@r-project.org>>> > wrote: > > > > Hello, all, > > > > I'd like to obtain the median age for a population in a > specific group > > of US Decennial census blocks. Here's an example of the problem: > > > > ## Example of calculating median age of population in census > blocks. > > library(tidyverse) > > library(tidycensus) > > > > counts <- get_decennial( > > geography = "block", > > state = "MD", > > county = "Baltimore city", > > table = "P1", > > year = 2020, > > sumfile = "dhc") %>% > > mutate(NAME = NULL) %>% > > filter(substr(GEOID, 6, 11) == "271101" & > > substr(GEOID, 12, 15) %in% c(3000, 3001, 3002) > > ) > > > > ages <- get_decennial( > > geography = "block", > > state = "MD", > > county = "Baltimore city", > > table = "P13", > > year = 2020, > > sumfile = "dhc") %>% > > mutate(NAME = NULL) %>% > > filter(substr(GEOID, 6, 11) == "271101" & > > substr(GEOID, 12, 15) %in% c(3000, 3001, 3002) > > ) > > > > I have two questions: > > > > 1. Is it mathematically valid to multiply the population of a > block by > > the median age of that block (in other words, assign the > median age to > > each member of a block), then calculate the median of those > numbers for > > a group of blocks? > > > > 2. Is raw data on the ages of individuals available anywhere > else in > > the > > census data? I can find tables such as P12, that breaks down the > > population by age ranges or bins, but can't find specific data of > > counts > > per age in years. > > > > Thanks for your advice and help. > > > > -Kevin > > > > _______________________________________________ > > R-sig-Geo mailing list > > R-sig-Geo@r-project.org <mailto:R-sig-Geo@r-project.org> > <mailto:R-sig-Geo@r-project.org <mailto:R-sig-Geo@r-project.org>> > > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > <https://stat.ethz.ch/mailman/listinfo/r-sig-geo> > > <https://stat.ethz.ch/mailman/listinfo/r-sig-geo > <https://stat.ethz.ch/mailman/listinfo/r-sig-geo>> > > > > > _______________________________________________ > R-sig-Geo mailing list > R-sig-Geo@r-project.org <mailto:R-sig-Geo@r-project.org> > https://stat.ethz.ch/mailman/listinfo/r-sig-geo > <https://stat.ethz.ch/mailman/listinfo/r-sig-geo> > _______________________________________________ R-sig-Geo mailing list R-sig-Geo@r-project.org https://stat.ethz.ch/mailman/listinfo/r-sig-geo
