Mean or Median -- what is your objective? Why it makes a difference.
Graphing data for insight.
Transformations - what are they used for and when to use them.
Treat outliers like children -- correct them when needed but never throw them out
Applying confidence, prediction and tolerance intervals to practical problems.
Hypothesis Tests -- how they work. Which types (parametric, nonparametric, permutation) to use?
Testing the mean/median/precision of two groups, more than two groups, matched pairs, and more.
Comparing data to a numerical standard.
Dennis Helsel (Ph.D. Environmental Science and Engineering) is a consultant and trainer on statistical methods for environmental and natural resource scientists through his firm, Practical Stats. He has authored three textbooks including Statistics for Censored Environmental Data using Minitab and R (2012), which presents methods for handling data below detection/reporting limits. He regularly conducts webinars, seminars and courses on topics such as Urban Legends in Environmental Statistics and Statistics for Contaminated Sites. He worked as a hydrologist, geochemist, and statistician for 30 years at the US Geological Survey before starting Practical Stats. For his training courses in applied statistics within and outside North America he received the Distinguished Achievement Award in 2003 from the American Statistical Association’s Section on Statistics and the Environment.
"I took the in-person version of this AES (1 and 2) course. It was absolutely excellent. I told my manager that it was the best lecture/workshop that I had ever been to! Of any kind, but especially of stats. Dennis took the time to explain the stats very clearly and identified very important things to consider, especially in terms of water chemistry data. I have always had trouble with trends of concentrations or loads over time because of the variability due to flow. Now I know how to deal with this situation, and will be able to separate natural from possible human-caused changes in water quality. I will be applying these techniques in the future, including multiple regression (while removing the effect of flow) and the Regional Kendall test to see if there is an increasing or decreasing trend watershed-wide. This will enable me to write a paper on trends in water quality in the Lake Simcoe river basin in Ontario." -- Eavan OConnor, Lake Simcoe Region Conservation Authority, Ontario, Canada