4 ms·

Very beautiful, poetic, relevant to a lot of the audience of HN, and props for detailing the tech behind it. Meanwhile... the highest and lowest hex I can spot

Very beautiful, poetic, relevant to a lot of the audience of HN, and props for detailing the tech behind it. Meanwhile... the highest and lowest hex I can spot is 1265 / 457 = a ratio of 2.76 with both endpoints having relatively steep curves compared to the rest of the histogram. With the graph's Z0 set to 457 and Zscale set to an arbitrary ratio, the sculpture-graph conveys the impression that there is a discrepancy of 5 or more times between the top of hill on the bottom tier vs the nearby flat area of the top tier. When the reality is something more like 1234 / 810 = 1.5

tantalor 10y ago
https://www.youtube.com/watch?v=14VYnFhBKcY https://www.youtube.com/watch?v=14VYnFhBKcY
- corysama 10y ago
  Very true. So, the question becomes: is this 3D printed chart misleading or is it focused on the relevant data? I must stress that I'm realize I'm being very analytic about a piece of art. As art and as a statement, I recognize that it is very well done. I just don't have much to say about it other than wondering if it is misleading.
  - dougmccune 10y ago
    Can the answer be both? If you're trying to use it as a chart to figure out home prices it doesn't provide enough information and it's misleading when it comes to determining the numeric relationship between regions. But if you're using it to get a sense of the impossibility of moving from one of the lower-cost parts of the city to one of the more expensive areas of SF, I think this captures that emotional feeling. I say that as a former SF homeowner who used to live right below the base of that big cliff face going from the Richmond up to Twin Peaks/Noe Valley. Looking at home prices in those areas gives you that feeling of smashing your face against one of those cliff walls.
    - corysama 10y ago
      I feel ya. Thanks for making this and thanks for sharing it!
    - Camillo 10y ago
      What are you talking about? The Richmond is not adjacent to Twin Peaks or Noe Valley. It's not even close. There are several neighborhoods in between.
      - dougmccune 10y ago
        You're right, but I was talking about the steady increase in price as you move from the Inner Richmond southeast toward Noe Valley on the sculpture. That cuts through the Haight, Cole Valley, Castro, etc. In terms of how I binned the data by hexagons, that's a diagonal progression across 4 adjacent hexagons, moving from an average price of $766/sq ft on the eastern side of the Inner Richmond across all the way up to $1,050 in Noe Valley. In the photos of the sculpture it might be hard to identify how much that rising part of the sculpture is actually moving south, but it is (and can be seen a bit better if you play with the model yourself or watch the animated gif of it rotating).
dougmccune 10y ago
Very good point! Yeah, please be advised there's artistic license taken and the Z-axis scale is arbitrary (well, not arbitrary, it's linear but stretched and certainly doesn't start at 0). You're totally right that the difference between the lowest areas and the highest isn't really as exaggerated as it appears. The real delta between lowest and highest is about 2.7x. I'd argue though that a difference between ~$500/sq ft vs $1,200/sq ft is enough of a difference to make the top of the range feel entirely out of reach for anyone living in the bottom of the range, and that's what the sculpture was meant to convey.
- arcticbull 10y ago
  My interpretation of it was that a 2.7X delta in price between lowest and highest isn't correlated linearly with affordability. i.e. a house that's twice as expensive per square foot doesn't make it half as affordable. People who already have to leverage themselves extensively to mortgage a property will never afford a property twice as expensive per square foot so it's actually infinitely less affordable, if you see what I mean.
  - deleted 10y ago
    [deleted]
- oldmanjay 10y ago
  That's the sort of "artistic license" that leads the adherents to the politics of envy to make proclamations about how life is somehow less worth living when you know someone else has more than you. When charitable, people call it hyperbole. At its core, it is simple emotional manipulation. At least you were subtle about it!
- ramses0 10y ago
  Truly, you'd want to pin rent as 25% of income and then have the height be related to where you would need to be on the U.S. income scale as a percentile to be able to afford it. ie: You've got a $899,000 home sale, that's supposedly a ~$4000/mo rent, which leads towards a "25% rule" of $16,000/mo income => $192,000/yr => which is supposedly 93.9%-ile. Going from $4000/mo => $5000/mo, it seems like it takes you to 96.8%-ile.
moseandre 10y ago
This is really nice art and data visualization too. It's common to scale the elevation of a topographic map to exaggerate features [1], even non-linearly [2]. If you try to 3d print a raised relief globe without exaggeration it is surprisingly flat. If you're buying an expensive classroom globe, the specs talk about the exaggeration [2]. This is a sculpture, so whatever goes, but perhaps the designer looked at the version without exaggeration and noticed that it looked less emphatic. I also think, as data visualization, this sculpture nicely shows the extreme change in price which occurs over small spatial distances. That's really important, and, actually, the tendency to make real estate price heatmaps with models that force continuity and prefer smoothness, like cubic splines, suppresses that aspect of the data. Railroad tracks and some beautification really are sometimes the only thing between million dollar homes and mobile parks. It would be cool to see this with neighborhood boundaries/names on the mesh. [1] "A raised-relief map or terrain model is a three-dimensional representation, usually of terrain, materialized as a physical artifact. When representing terrain, the vertical dimension is usually exaggerated by a factor between five and ten; this facilitates the visual recognition of terrain features." https://en.wikipedia.org/wiki/Raised-relief_map https://en.wikipedia.org/wiki/Raised-relief_map [2] "Raised Relief: Yes. Elevations from 0-3,280 feet are magnified 60 times, higher elevations and ocean floor are exaggerated by 40 times." http://www.1worldglobes.com/1WorldGlobes/classroom_relief_globe.htm http://www.1worldglobes.com/1WorldGlobes/classroom_relief_gl...

tantalor 10y ago

https://www.youtube.com/watch?v=14VYnFhBKcY https://www.youtube.com/watch?v=14VYnFhBKcY

corysama 10y ago
Very true. So, the question becomes: is this 3D printed chart misleading or is it focused on the relevant data? I must stress that I'm realize I'm being very analytic about a piece of art. As art and as a statement, I recognize that it is very well done. I just don't have much to say about it other than wondering if it is misleading.
- dougmccune 10y ago
  Can the answer be both? If you're trying to use it as a chart to figure out home prices it doesn't provide enough information and it's misleading when it comes to determining the numeric relationship between regions. But if you're using it to get a sense of the impossibility of moving from one of the lower-cost parts of the city to one of the more expensive areas of SF, I think this captures that emotional feeling. I say that as a former SF homeowner who used to live right below the base of that big cliff face going from the Richmond up to Twin Peaks/Noe Valley. Looking at home prices in those areas gives you that feeling of smashing your face against one of those cliff walls.
  - corysama 10y ago
    I feel ya. Thanks for making this and thanks for sharing it!
  - Camillo 10y ago
    What are you talking about? The Richmond is not adjacent to Twin Peaks or Noe Valley. It's not even close. There are several neighborhoods in between.
    - dougmccune 10y ago
      You're right, but I was talking about the steady increase in price as you move from the Inner Richmond southeast toward Noe Valley on the sculpture. That cuts through the Haight, Cole Valley, Castro, etc. In terms of how I binned the data by hexagons, that's a diagonal progression across 4 adjacent hexagons, moving from an average price of $766/sq ft on the eastern side of the Inner Richmond across all the way up to $1,050 in Noe Valley. In the photos of the sculpture it might be hard to identify how much that rising part of the sculpture is actually moving south, but it is (and can be seen a bit better if you play with the model yourself or watch the animated gif of it rotating).

dougmccune 10y ago

Very good point! Yeah, please be advised there's artistic license taken and the Z-axis scale is arbitrary (well, not arbitrary, it's linear but stretched and certainly doesn't start at 0). You're totally right that the difference between the lowest areas and the highest isn't really as exaggerated as it appears. The real delta between lowest and highest is about 2.7x. I'd argue though that a difference between ~$500/sq ft vs $1,200/sq ft is enough of a difference to make the top of the range feel entirely out of reach for anyone living in the bottom of the range, and that's what the sculpture was meant to convey.

arcticbull 10y ago
My interpretation of it was that a 2.7X delta in price between lowest and highest isn't correlated linearly with affordability. i.e. a house that's twice as expensive per square foot doesn't make it half as affordable. People who already have to leverage themselves extensively to mortgage a property will never afford a property twice as expensive per square foot so it's actually infinitely less affordable, if you see what I mean.
- deleted 10y ago
  [deleted]
oldmanjay 10y ago
That's the sort of "artistic license" that leads the adherents to the politics of envy to make proclamations about how life is somehow less worth living when you know someone else has more than you. When charitable, people call it hyperbole. At its core, it is simple emotional manipulation. At least you were subtle about it!
ramses0 10y ago
Truly, you'd want to pin rent as 25% of income and then have the height be related to where you would need to be on the U.S. income scale as a percentile to be able to afford it. ie: You've got a $899,000 home sale, that's supposedly a ~$4000/mo rent, which leads towards a "25% rule" of $16,000/mo income => $192,000/yr => which is supposedly 93.9%-ile. Going from $4000/mo => $5000/mo, it seems like it takes you to 96.8%-ile.

moseandre 10y ago

This is really nice art and data visualization too. It's common to scale the elevation of a topographic map to exaggerate features [1], even non-linearly [2]. If you try to 3d print a raised relief globe without exaggeration it is surprisingly flat. If you're buying an expensive classroom globe, the specs talk about the exaggeration [2]. This is a sculpture, so whatever goes, but perhaps the designer looked at the version without exaggeration and noticed that it looked less emphatic. I also think, as data visualization, this sculpture nicely shows the extreme change in price which occurs over small spatial distances. That's really important, and, actually, the tendency to make real estate price heatmaps with models that force continuity and prefer smoothness, like cubic splines, suppresses that aspect of the data. Railroad tracks and some beautification really are sometimes the only thing between million dollar homes and mobile parks. It would be cool to see this with neighborhood boundaries/names on the mesh. [1] "A raised-relief map or terrain model is a three-dimensional representation, usually of terrain, materialized as a physical artifact. When representing terrain, the vertical dimension is usually exaggerated by a factor between five and ten; this facilitates the visual recognition of terrain features." https://en.wikipedia.org/wiki/Raised-relief_map https://en.wikipedia.org/wiki/Raised-relief_map [2] "Raised Relief: Yes. Elevations from 0-3,280 feet are magnified 60 times, higher elevations and ocean floor are exaggerated by 40 times." http://www.1worldglobes.com/1WorldGlobes/classroom_relief_globe.htm http://www.1worldglobes.com/1WorldGlobes/classroom_relief_gl...