Playing games with the data on home size


To the Editor:

I am writing in response to a Letter to the Editor [Zoning based on bad analysis, by Robert Kenney, April 4]. I found some issues with the argument he made regarding the increase in housing size in recent years as stand-alone rationale for opposing the housing square footage limit that will be considered by the people of Chilmark. First, following Mr. Kenney’s logic we should adjust up the BMI and obesity scales because Americans have gotten bigger in the past few decades, and then by that logic determine that we don’t have an obesity problem in the U.S. Problem solved, and tell my wife I’m done with dieting.

More specifically, Mr. Kenney’s data point that underpins his argument, the selection of the past 15 years to get the average square footage of houses, is even more arbitrary than the zoning board’s metric incorporating all houses in Chilmark, as it slices the overall sample to benefit his end argument, while the zoning board considered the entire sample. In fact, we should ask Mr. Kenney why he doesn’t use 20 years, or 30 years, or 50 as his metric? What is so special about 15 years?

I am guessing the selection of time period had something to do with the results you would get from that average, which is a very disingenuous way to try and use data to prove a point, instead of looking at the data and only then drawing conclusions. Or, if I’m mistaken, Mr. Kenney should clarify the specific logic for selecting the past 15 years as your window and why it is a more appropriate metric than any other, and in particular the metric that includes the entire sample which the zoning board used.

Mr. Kenney lives in Chilmark, so his voice and the voices of his neighbors matter most on this issue — far more than mine, to be sure, since I don’t even live in my hometown of West Tisbury any more. I just have problems with the logic of his argument that recent history is the key factor, and I find fault with his selective use of data without explaining how it was identified ex-ante as the right metric, and is not actually just data hand-picked to support his predisposition on the issue.

If you really want to make an argument for why this is bad policy, focus on the arbitrariness of the 3,500-square-foot level, in the same way I critiqued the arbitrariness of Mr. Kenney’s 15-year metric. This debate reminds me of interest rate caps in consumer lending, where there is a sense that something is not right about predatory loans, and a decision to do something to control this sector is called for. At the same time, it’s also hard to say a certain percent interest rate, say 200 percent, is “too much,” while a number right below it, say 199 percent, is okay. Some governments have addressed this by placing the interest rate cap at such a high level that there is very little argument that a product at that cost is of end benefit to consumers.

So maybe the square footage is set too low at 3,500, and should be set at a level that covers only the most extreme cases, as Mr. Kenney suggests. Regardless of where the line is, the key point is that we will never be able to set a line that perfectly divides “okay/not okay” cleanly, and that should not be the key argument. The key argument should be whether the town of Chilmark’s population believes there should be a limit on housing size. The rest is just arguing over the exact number, which is a discussion that could benefit from dissenting views like Mr. Kenney’s and lead to a compromise that satisfies those that share his opinion, without having to throw out the concept as a whole. As for those who say “show me the direct harm large houses are causing before you enact this zoning rule,” they have the burden of proof backwards. The burden falls on you to show why limiting housing size will cause harm to hypothetical future large home builders, if you want to stop a democratic and local government from exercising its authority.

Again, this is for Mr. Kenney and Chilmark to decide, but let’s at least be honest about the way we use the data selectively, to make our personal case of how much is too much.

Rafe Mazer

Washington, D.C., and West Tisbury