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Sample Design: GRTS - John Day LWD 2

Sample Design: GRTS - John Day LWD 2
ID: 49
State: Finalized
  • State: Finalized
  • Owner: Matt Deniston
  • Spatial Design Category: Generalized Random Tessellation Stratified (GRTS)
  • Data Repository: <none>
  • Sites in Design: 160
  • Has Location Privacy: No

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The details of this Sample Design, including all the parameters used to generate it, are included below. Sample designs must belong to a Study Design.



Sample Design Parameters

Start Year


Study Design






Map of Sites

Stratum Panel Occasion

Area of Inference


AOI Notes


This sample design is based on master sample: Columbia Basin Master Sample

Details of this master sample:


This sample design started with an initial frame of 551,046 sites, based on its master sample. The criteria (based on the master sample's attributes) were then used to refine the sample frame down to 283 sites:

Criteria Group 1
  HUC 4 Code (Subbasin) Is Equal To 17070201

Criteria Group 2
  Strahler Order Is Equal To 4 OR
  Strahler Order Is Equal To 5 OR
  Strahler Order Is Equal To 6

Target Population


Panel designs can help address sampling objectives by increasing the total number of samples at a lower overall cost. A common panel structure involves one or more panels with a high revisit frequency (e.g. an “Annual” panel), and other panels with a lower revisit frequency (e.g. a three year “Rotating” panel).

Panel Sampling Occasion (3 Year(s))
# Panel Name Panel Abbr. 1 2 3
Rotating 1
Rotating 2
Rotating 3

This design uses the following attributes to create the stratification shown below. Each row in the table represents a stratum. This design’s panels are also shown in the table, even if it uses only a single, default panel.

Sample Attributes
  Attribute   Values In Frame
  SO 2 Values: 4, 5
Attributes # Sites In Frame Frame Length (km) Stratum Attributes Panels
SO Stratum Name Stratum Abbr. Annual Rotating 1 Rotating 2 Rotating 3 # of Sites
4 183 0 Strahler 4 S4 15 10 10 10
5 100 0 Strahler 5 S5 15 10 10 10
TOTAL 0 km      

Below is the complete list of sample sites that were drawn using the criteria for this sample design.

Number of sites before generating the GRTS sample: 283
Number of sites after generating the GRTS sample: 160
Number of oversamples: 70
Number of panels: 4
Number of strata: 2




The histogram charts below show the distribution of this sample design’s sites across the various panels and strata.

  Schema   Attribute   Description