The NABat program uses a “Master Sample” approach with a grid-based frame. This approach assigns a spatially balanced and randomized ordering of all 10X10 km grids from a finite grid-based sampling frame using a Generalized Random-Tessellation Stratified (GRTS) survey design. The data contained in this space contain provisional NABat “Master Sample” grid packages. There are two primary “Master Sample” grid packages available: Continental United States (CONUS) and Alaska/Canada. Each “Master Sample” grid package include shape files of the entire geographic extent of the finite grid-based sampling frame as well as the spatially balanced and randomized ordered list of the 10x10km grid cells. Subsamples (e.g., monitoring site selection) [...]
Summary
The NABat program uses a “Master Sample” approach with a grid-based frame. This approach assigns a spatially balanced and randomized ordering of all 10X10 km grids from a finite grid-based sampling frame using a Generalized Random-Tessellation Stratified (GRTS) survey design.
The data contained in this space contain provisional NABat “Master Sample” grid packages. There are two primary “Master Sample” grid packages available: Continental United States (CONUS) and Alaska/Canada. Each “Master Sample” grid package include shape files of the entire geographic extent of the finite grid-based sampling frame as well as the spatially balanced and randomized ordered list of the 10x10km grid cells. Subsamples (e.g., monitoring site selection) from this list can be made following the GRTS order, ensuring both randomization and spatial balance.
In addition to each complete “Master Sample” grid package (covering the entire geographic extent of the represented area), individual packages were created for select States, Provinces, and Areas of Interest. These packages also include shape files and the spatially balanced and randomized ordered list of the 10x10km grid cells for the selected geographic area. Subsamples (e.g., monitoring site selection) from this list can be made following the GRTS order, ensuring both randomization and spatial balance.
Please note, download and use of these data while in a provisional state are at the risk of the user. There is no guarantee that the final version of these grids will look like the current grids.
