census data created in countries across the world. on this map of the dominican republic, irregular red lines surround subnational administrative units for which census data is available. one problem for balk's team is how to reconcile these data with precise grid-format satellite data, shown here in blue. to obtain boundaries of urban areas, a third source of information was used -- nighttime images of the earth from space. balk: noaa produces a nighttime lights data set that was measured in 1994 and 1995, and it's a globally consistent data set. that means they use the same measures everywhere. it measures brightness of places. we combined the lights data with the population data, as well as a few other data sets, to make sure that we can confirm each light is actually a population place. narrator: using a combination of various population and geographic data sets, balk is able to determine how many people live in low-elevation coastal zones. balk: this is southern vietnam. so, we see the white areas are administrative boundaries. the red areas indicate the nighttime lights -- the urban areas. and this blue data set is the elevation zone tha

census bureau, average household income was $73,000 in 2014 which is the last year data was available but just throwing that number out there doesn't mean a whole lot. there are a lot of factors to be taken into account. when you look at the average where you live, $73,000 could be a lot or a little. another factor is the size of the family. $73,000 stretches differently depending on whether it's feeding a family of two or a family of four or five. something else interesting the data shows is how the age of the head of the household affects the money brought in. 35 to winner, the average $71,000. 55 to 64, median income goes down to $60,000. and this is really disheartening when the head of the household is 65 years or older, the median household income just $37,000. >>laura: some people can't even afford to buy a sandwich. they go hungry. thousands of men, women and wa-wa is doing something to help and alcides segui is at the newest location in brandon to explain. good morning. >>reporter: good morning to you. yeah, they're opening the 100th wa-wa here in the state of florida. to cel

education, linguistic isolation, which is definitely a feature in san francisco, poverty and on employment. their data compares every-the frequency of these characteristics in census tracts, and each census tract to every other census tract across the state of california. so that all census tracts are essentially ranked in terms of their degree of this advantage. we have set the line at 20% so in other words the highest 20% rates of these in census tracts are in the communities of that are referenced in the charter low-income and disadvantaged. we took the data and were able to isolate the census tract data just for san francisco so that to be more true to the spirit of the charter comparing each census tract to all other census tracts in the city. that is what this map shows. the very darkest purple there the to darkest color shades are the top 20% of frequency of these characteristics. that doesn't show very well for the audience but i hope that commissioners can see. and we overlaid that data to a map with our parks. again, census tracts with the highest 20% of population characteristics compared to the city a solar designated as equities owns. these are the pl