2 Introduction

2.1 Objective

• Demonstrate the functionality provided by the mmir R-package for calculating biological metrics for the development and/or use in an MMI or IBI.

2.2 What is an MMI?

• Multi-Metric Indices (MMIs) or Indices of Biotic Integrity (IBIs) are models that summarize multiple aspects of a biological community of interest (e.g., richness, diversity, relative abundance, tolerance, and functional feeding group) into a single numeric or categorical value representing ecological condition.
  • considered a robust measure of water quality because it represents more than a snapshot in time
  • have been around for nearly 40 years

2.3 Need

• MMIs are widely used by U.S. federal and state agencies to assess water quality but there is no R-package available to simplify and standardize metric calculations.