Accuracy, Precision and SignificanceThe difference between accuracy-being close to the actual value-and precision-how close values are to one another-is well known.  These values can also be very misleading.  When you forecast or estimate greenhouse gas emissions, you want results that are also reliable and useful to you in designing your project.  You want significance and relevant information that will help you make decisions.  You need to rely on the tools that will give you what you need in the context of your other order-of-magnitude inputs: market, politics, financing, phasing.