having some like this and then—as new products come on—be able to add in different kinds of devices out in the field.

So I’m probably by now way over my time, but let me just say: there are a lot of problems here. And why are we doing this? Well, almost everything is tied to a point on the ground. This is becoming an increasingly common mode of communicating: we have our MapStats up for the federal statistical community. If you take the “geo” out of what we’ve been talking about today, you basically get the flowcharts that were up yesterday. So we’re getting very used to interacting with visual information. And geospatial data are really rich in information content—much more so than a list of addresses—and I think that there’s a lot to take advantage of there. And the quality of the data is increasing, so we can use it in a way that will feed into our measurement error structures. So, that’s about it.

CORK: We can take one or two questions for Sarah while we switch computers up here.

PARTICIPANT: How large are the files? You said that they are big …

NUSSER: They range from just a few kilobytes—which is what a vector file would be—into megabytes. Generally you’re not dealing in gigabytes, but it’s not hard to get there fast with a few images. So this presentation which had a number of clips in it is probably 10 megabytes. When we think about the data for the National Resource Survey which we do—which has about 300,000 sampling units—we’re definitely thinking terabytes for that data.

PARTICIPANT: So that is something you really need to think about.

NUSSER: You really do, and I guess in part that’s why we’re not thinking so much about data structures but rather how can you work with—for example—storing this in different places and being able to pull it into a computation server to break it up and send it into the field, rather than having things set up in a prescribed way before you go out in the field.

PARTICIPANT: [inaudible] So would you need some kind of dial-up connection?

NUSSER: It can be slow, and so if you’re doing dial-up, this is one of the settings we’re working with in the project, where you have pretty poor communication. So you want to take just a subset of the data and send it out, something that’s small, that you can send out via a wireless or dial-up line, or whatever. And we have a long ways to go. Yes, Mike?

COHEN: Handheld devices are being trumpeted for use in data collection for the 2010 census. Do you see the need for different types of devices inside the blue line versus outside the blue line?

NUSSER: Sorry, could you give me the jargon?



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