N-STEPS - Statistical Tools
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Fact Sheets
Fact sheets on statistical information commonly used in nutrient criteria development and links to other statistical resources.
- Change-point analysis is a method for identifying thresholds in relationships between two variables.
Change-Point Analysis Fact Sheet - Correlation is a measure of the strength of a relationship between two variables.
Correlation Fact Sheet - Loess stands for locally estimated scatterplot smoothing (lowess stands for locally weighted scatterplot smoothing) and is one of many non-parametric regression techniques.
Loess or Lowess Fact Sheet - Regression is one of the most common statistical modeling tools used, regression is a technique that treats one variable as a function of another.
Regression Fact Sheet - A conditional probability is the probability of an event occurring when some other event has occurred.
Conditional Probability Fact Sheet - Classification, in the nutrient criteria process, is the process of identifying groups of sites that have comparable characteristics and for which comparable nutrient behavior is expected.
Classification Fact Sheet - Weighted averaging is a method for computing an average where some values receive greater weight than others.
Weighted Averaging Fact Sheet
The following links exit the site Exit
Statistics Resources
- List of webpages that Perform Statistical Calculations - Exhaustive list of statistical test.
- Vassar College “VassarStats” page - Online calculator of statistical functions.
- College of St. Benedict, Statistics Calculators - Online calculator of statistical functions.
- GraphPad QuickCalcs - Online Calculators For Scientists to Analyze, Graph, and Organize Data.
Software
- R - Widely used free software environment for statistical computing and graphics. It compiles and runs on a wide variety of UNIX platforms, Windows and MacOS.
- R Studio - Provides a graphical interface for use with R.
- Free Statistical Packages (BUGS, R, STATS) - Free software that will run different statistical tests.
- University of Minnesota - Arc Software - A package for regression analysis designed as a companion to the book Applied Regression Including Regression and Graphics by R.D. Cook and S. Weisberg.
- Statistical Analysis Tools - Analysis programs, power analysis, stats tables (t distribution, chi square, normal distribution, etc.); describes univariate data, curve fitting, and distribution-free tests.
Open Source Statistics Training
- Coursera homepage and Coursera Statistical Topics - Offers over 700 free courses on a variety of topics; with over 50 participating universities offering statistical courses.
- Coursera offers a data science specialization in a 9 part series that may be of interest.
- Rice University Virtual Statistics lab - Stats tools and case studies, demonstrations, and books for background information and resources.
- Rice University Online Statistics Book.
- Carnegie Mellon University - Through its Open Leaning Initiative offers courses in Statistical Reasoning and Probability and Statistics among other courses.