tag:blogger.com,1999:blog-20276223.post983386442713012211..comments2023-03-26T06:16:17.302-05:00Comments on Einar Diaz: Why the maps annoy meptbhttp://www.blogger.com/profile/03839114506627123131noreply@blogger.comBlogger3125tag:blogger.com,1999:blog-20276223.post-11949961748816919692010-01-12T03:38:14.958-06:002010-01-12T03:38:14.958-06:00As a helpful example of a map I liked, Very Large ...As a helpful example of a map I liked, Very Large Array had a map yesterday of points advertised in craigslist as "Williamsburg." For some reason, point-level data is already more appealing to me than polygon-level. But the claims were modest: This is what Williamsburg looks like, if you believe Craigslist. <br /><br />It would've been interesting to see what that "Greater Billyburg" is ALSO called in Craigslist, since I doubt every apt rented in "East Williamsburg" is called that in Craigslist, but I could be wrong. <br /><br />Still, all it shows is expanded boundaries and gives a sense of how much repetition gives the expanded boundary meaning--we can see and perhaps even count how many points out of the total fall outside of "official" Williamsburg, whatever that is.Moacirhttps://www.blogger.com/profile/00601713037161663091noreply@blogger.comtag:blogger.com,1999:blog-20276223.post-76685915591988827432010-01-12T03:21:31.317-06:002010-01-12T03:21:31.317-06:00Yeah, I realise the inherent elitism in the commen...Yeah, I realise the inherent elitism in the comment, which is why I started with the idea of how scientists bristle when they see their techniques coopted in a loosey goosey way. I don't think the comparison to high/low culture is exactly right, though.<br /><br />The issue is taking data (like from an xls), re-presenting it in a different way (spatially), and expecting conclusions to simply appear from the re-presentation. It doesn't work that way, since by presenting the data spatially, there are new concerns to take into account.<br /><br />Part of me is happy to see geographic literacy increase. No, all of me is. But this is doing more than that. It's preaching the message that "if you map it, a conclusion will come." (If it wasn't, then it's totally just an idle plaything.) But, again, just mapping it isn't enough, just like turning a concordance into a Wordle isn't enough. It's a step in the analytical process, but not the last one.<br /><br />I should've done a better job with autocorrelation, so let me start from scratch:<br /><br />You have a field of polygons (ZIP codes of NYC) all colored different ways. The eye is famously bad at telling you if the colors are clustered, random, or dispersed. And *by how much*. Now, autocorrelation assumes, via the first law of geography, that everything that happens is related (no independent observations), but whatever happens close is more related. This means that we would expect data about the human world to be clustered. <br /><br />Before doing statistical analysis on a set of geospatial data, however, you need to know how autocorrelated the data is. How much more clustered or dispersed than random it is, since most statistical tools (regression, etc.) assume/require independence. Of coruse, regression requires a second variable, and we don't get that here, anyway. Just amathematical ordinals.<br /><br />So for the purposes of seeing what your neighbors rent (or dont), tests like Moran's I (testing for general correlation) or Getis-Ord (testing for clustering of certain values, iirc) aren't really necessary. But they are necessary if you want to quantify or make strong claims about clusters. <br /><br />Another way: how much of Tyler Perry's reach is random chance, how much is that any two neighboring polygons will likely have similar values, and how much is something "anthropological"? The maps as presented are unable to even start answering any of these questions.<br /><br />Yet aren't the maps there precisely for us to try and answer these questions for fun? And this *promotes* literacy? By encouraging bad reading?<br /><br />Finally, I didn't lash out at ordinal data enough in my original post, but after I thought about what I'd LIKE the maps to look like, I think I decided that the best, given ZIP code-level data, would be per-movie rental as a percentage of total households or netflix households per ZIP. Which feels more useful knowing: a) Slumdoggy was the third most popular movie in this ZIP or b) 45% of netflix households rented this movie (with the maximum movie being 50%, the mean being 25%, and the variance being .014 or whatever).Moacirhttps://www.blogger.com/profile/00601713037161663091noreply@blogger.comtag:blogger.com,1999:blog-20276223.post-8026301704708881692010-01-11T15:04:19.312-06:002010-01-11T15:04:19.312-06:00Agreed. Though this line of argument:
"If th...Agreed. Though this line of argument:<br />"If the point of the maps is to show that, yes, this shit is hell of spatially correlated, well, big deal. Again, there's nothing new in telling me that shit spatially correlated"<br /><br />doesn't take you all that far. After all, couldn't one say there's nothing new in telling us that maps are not only imperfect representations of reality, but encode and reproduce power relationships? Or that our mainstream organs of knowledge making aren't intellectually rigorous?<br /><br />I like to think that the good these mapping tools do to promote geographical literacy and get people to visualize their world in different ways outweighs the pitfalls. A lot of people will merrily go about the business of flattering themselves (a wonderful way of putting it, btw), me included, but I also think plenty of other people will bump up against the inadequacy of this first wave of tools; the people with tactical knowledge beyond the comprehension of the NYT/Google man on the skyscraper. They'll push for (perhaps get hired to develop) more refined tools that will threaten the real problem: the inaccessibility of ESRI and the theoretical expertise housed in higher education.<br /><br />Basically, we can re-stage the debate around consumer culture: inherently insidious and depoliticizing, or do we give the audience a little more credit and say that there's a lot of play, some of which might develop into serious play. Your analysis has a little of the high/low culture elitism: it seems to assume that such gauche maps will only produce regressive, conservative meaning and never inspire any sort of higher order alternative thinking about the world we live in<br /><br />My counter crank: you need to come back from Paris soon and mingle with the masses.CZAhttps://www.blogger.com/profile/17768810140187824016noreply@blogger.com