ConstructionSurvival Bias Theory: How it Applies to Housing & Construction

Drive around the streets of downtown Charleston SC and you will see many examples of the cliché at the heart of our beautiful city – that is, very beautiful, old buildings in their original settings.  How many a recent “stick-built ” subdivision will stand such a test of time and what has changed so dramatically in our expectations of what makes a quality build?  Well the analysis and determination may not in fact, appear to be as it seems. Here’s why …

Back in World War II when we were facing some pretty dark days sending our sons off to war, one primary concern of the Allied military was to make sure that those lives were not wasted in futile ways so obviously occurring on the Eastern front.  A key tool in that fight was statistics and the scientific analysis of data as a tool to inform future design and strategy. Enter a Romanian mathematician by the name of Wald.  He was asked by the US Navy to analyze damage patterns on returning aircraft and from that infer where better to reinforce and protect the structure. His report was a surprise.  He said to reinforce where the bullet holes were at a minimum not a maximum (this being mostly around the engines and fuel tanks). His reasoning was that the holes reported upon represented those visible on returning aircraft and not those that had already been shot from the sky.  If protection was given to the areas where bullet hole data was missing, then those missing aircraft may have made it back home.  A counter intuitive but important observation for which many a Veteran owed his life.  It’s called Survival Bias and has parallels in many fields of our lives.

Forward to our observation of the many historic homes in Charleston SC.  They are here because they were built well to start with – beautiful, structurally sound, and well-constructed homes.  Many homes in the 18th and 19th Centuries were simply not built as well and have disappeared in the intervening years.  Have a look at a Halsey Map to see great swathes of our city destroyed over the years by war, earthquake, tempest or fire. An example would be the brick-built homes that line the streets of Ansonborough that have lasted, where the older wooden structures fell to a huge City fire in the 19th century.  So when we see home after home in prime condition, it’s not that these homes were generally built better to start with, or cared for better in the interim, it was because all the sub-par homes that were thrown up for a low price never lasted and fell by the wayside before our generation ever came along.

Moving on to the present day, our renovation and construction crews build and restore fine homes (and grand houses such as The Gadsden House).  Homes that will last the years, last longer than you or I and be viewed by future visitors as part of the historic fabric of the city. Those visitors will ask in their future times,  “Why people don’t build homes like they used to? ” and the answer will come from what they can’t see. It will come from reflecting on what is missing and it will come from the mind of a Romanian mathematician who, in theory, did not even have the security clearance to read his own reports.

NOTE: When building your home, spend as much effort in what cannot be outwardly seen as you do in what remains visible. Then your home and investment will last the test of time as many already have on the historic and picturesque streets of downtown Charleston SC.