Statistics is one of those classes that I was forced to take. As an ecologist I would much rather be out watching birds, measuring fish, or hiking through a swamp than sitting in a windowless classroom looking at a power point of numbers. Despite the monotonous nature of the class it is likely one of the most important aspects of my education. It is a class everyone should be required to take, even if the only thing they learn from it is to question numbers.
Numbers seem factual. We are taught from a young age that 2+2 = 4, and that 4 means 4. Statistics is not a way to manipulate numbers, it is a way to express concepts as numbers, but simple confusion about the math, the source and the interpretation of these numbers can lead to misunderstandings with far reaching consequences. I realized this recently as I delved into the world of recycling.
I was upset, though not necessarily shocked, to learn that the US plastic recycling rate is 9%. This is 5% below the global recycling rate. However, the US claims a 34.5% recycling rate. The discrepancy in these numbers made me quickly question what was being represented, and how it was being measured. Many times statistics aren’t accompanied by accurate descriptions or citations. Meaning I had to go searching for the answer.
The United States 34.5% recycling rate would be better described as a recovery rate. Meaning 34.5% of municipal waste is recovered. Now this includes green and compostable waste as well as recyclables (including glass, plastic, paper, cardboard, etc) and is measured by weight.
Only 9.2% of plastics are recovered, which represents 4.6% of the total weight of recovered materials. Not surprisingly, glass, paper and metals are recycled at much higher rates.
Read through the report yourself here.