Course Documents -> Week 9 -> Rainfall Analysis

Download this spreadsheet and then following the instructions below, explicitly!

This is an exercise in looking for subtle differences in data that may reflect measurement error or otherwise suggest the credibility of one of the data sets is in question.

  1. Construct the moving average data for annual rainfall for Salem, Eugene, and Portland and put the output in columns H3:H57, I3:I57, and J3:J57, respectively. Use an interval of 7 years.

  2. After you have done this, the upper two plots should fill out. The left plot compares Eugene (Red) to Salem (blue) and the right plot is Salem (blue) compared to Portland (red)

  3. Subtract the average of the seasonal data for the whole data set from each individual seasonal year: for Salem put that in columns K3:k57; Eugene goes in L3:L57

  4. After you have done this, the bottom plot will fill out with Salem on the X-axis and Eugene on Y-axis

  5. Also the bottom pair of graphs (Salem on Right, Eugene on Left are now populated)