Before you can interpret the numerical value of r, you need to determine if it was appropriate to calculate r to begin with. The Pearson correlation coefficient, r, describes the strength and direction of a linear relationship between two variables. The first step in exploring a linear relationship is to generate the scatterplot, which you learned about in the previous section.
New Smog Check Test Smog Check Program's Updated Test Technology Californians getting Smog Checks today may notice that the traditional tailpipe test used for many years has been replaced by a quicker, computer-based test for gasoline-powered cars model-year 2000 and newer, and for most diesel vehicles that are model-year 1998 and newer.
A gas-powered vehicle is excused from Smog Check until it is seven model-years old. Department of Motor Vehicles (DMV) computers are designed to recognize the exemption and process your renewal accordingly. Contact DMV if you think there is an error.