# DoD Thresholding

### Overview

This exercise contrasts the three most common forms of thresholding DoDs: i) Simple minimum level of detection, ii) propagated errors, and iii) probabilistic. We use the GCD Add-In to facilitate the analysis.

### Data and Materials for Exercises

#### Datasets

I_Thresholding.zip File of Data for this Exercise. Data from:

#### Prerequisite for this Exercise

• Some ArcGIS experience
• ArcGIS 10.X w/ Spatial Analyst Extension

## Overview of Thresholding

GCD Provides three primary ways for you to threshold data (all using exclusion):

#### Simple Minimum Level of Detection

In this video tutorial we explain how to use the GCD `Change Detection` panel to to a basic DoD Analysis with simple minimum level of detection thresholding. This is the equivalent of the raster calculator operation in the 03. Simple DoD in Raster Calculator tutorial.

#### Propagated Errors

In this video tutorial we explain how to use the GCD `Change Detection` panel to to a DoD Analysis with propagated errors (from error rasters in the `Survey Library`) to establish the level of detection threshold.

#### Probability

In this video tutorial we explain how to use the GCD `Change Detection` panel to to a DoD Analysis with probabilistic thresholding based on a confidence interval.

This tutorial corresponds with topic G. Thresholding Alternatives in the GCD Workshop. See the lecture materials there for more background on the underlying theories for these methods.

#### Extra:

How to Make your own Elevation Change Distribtuions

### Step by Step

#### Part 1 - Simple minLoD

How to do in GCD 7:

How to do in GCD 6:

#### Part 2 - Propagated Error

How to do in GCD 7:

How to do in GCD 6:

#### Part 3 - Probabilistic

How to do in GCD 7:

How to do in GCD 6: