topic Newbie question about hot spot analysis in Spatial Statistics Questions https://community.esri.com/t5/spatial-statistics-questions/newbie-question-about-hot-spot-analysis/m-p/544155#M1765 <HTML><HEAD></HEAD><BODY><SPAN>My GIS experience has been mostly with digitization and a bit of web development, but a coworker asked for some assistance in an analysis project he's working on so I offered to help.&nbsp; I think I'm on the right track but I wanted to run this by people with more experience who might offer some insight.</SPAN><BR /><BR /><SPAN>I've attached a picture of the study area we're looking at.&nbsp; We're trying to determine a preferred habitat type for an invasive fish in our waters.&nbsp; Biologists made multiple surveys on a boat shocking the waters to count the number of fish found in a particular tributary.&nbsp; The red line in the picture represents the GPS trackline of the boat during one survey, and each point represents one of the invasive fish.&nbsp; I'm using the optimized hotspot analysis tool in 10.2 to determine if there are any locations along the stream in which fish seem to be clustered.</SPAN><BR /><BR /><SPAN>I used two different methods so far.&nbsp; First, I tried using the Count Incidents Within Aggregation Polygons method, using a 10x20m grid I created based on the GPS trackline.&nbsp; My concern with that was the fact that some of the incidences would fall outside of this grid - am I correct in assuming that any incidences outside of the polygons wouldn't factor into the analysis?</SPAN><BR /><BR /><SPAN>In my second attempt I used the Count Incidents Within Fishnet Polygons (with no bounding polygon).&nbsp; Both results returned a few hot spots more-or-less in the same location, but I'm thinking this method is ideal as every incident fell within one of the polygons.</SPAN><BR /><BR /><SPAN>Am I on the right track?&nbsp; Is there a better tool, or more ideal preferences I should be using?&nbsp; Are there any concerns I should be aware of when using this tool in stream/aquatic areas as the spatial distribution is far more confined than over a terrestrial study area?&nbsp; Lastly, I've looked through some literature and videos about this tool, but if anyone has any recommendations of something I could read/watch to understand spatial statistics and clustering better, it would be greatly appreciated.</SPAN></BODY></HTML> Thu, 12 Dec 2013 17:14:53 GMT BrettGreenfield__DNR_ 2013-12-12T17:14:53Z Newbie question about hot spot analysis https://community.esri.com/t5/spatial-statistics-questions/newbie-question-about-hot-spot-analysis/m-p/544155#M1765 <HTML><HEAD></HEAD><BODY><SPAN>My GIS experience has been mostly with digitization and a bit of web development, but a coworker asked for some assistance in an analysis project he's working on so I offered to help.&nbsp; I think I'm on the right track but I wanted to run this by people with more experience who might offer some insight.</SPAN><BR /><BR /><SPAN>I've attached a picture of the study area we're looking at.&nbsp; We're trying to determine a preferred habitat type for an invasive fish in our waters.&nbsp; Biologists made multiple surveys on a boat shocking the waters to count the number of fish found in a particular tributary.&nbsp; The red line in the picture represents the GPS trackline of the boat during one survey, and each point represents one of the invasive fish.&nbsp; I'm using the optimized hotspot analysis tool in 10.2 to determine if there are any locations along the stream in which fish seem to be clustered.</SPAN><BR /><BR /><SPAN>I used two different methods so far.&nbsp; First, I tried using the Count Incidents Within Aggregation Polygons method, using a 10x20m grid I created based on the GPS trackline.&nbsp; My concern with that was the fact that some of the incidences would fall outside of this grid - am I correct in assuming that any incidences outside of the polygons wouldn't factor into the analysis?</SPAN><BR /><BR /><SPAN>In my second attempt I used the Count Incidents Within Fishnet Polygons (with no bounding polygon).&nbsp; Both results returned a few hot spots more-or-less in the same location, but I'm thinking this method is ideal as every incident fell within one of the polygons.</SPAN><BR /><BR /><SPAN>Am I on the right track?&nbsp; Is there a better tool, or more ideal preferences I should be using?&nbsp; Are there any concerns I should be aware of when using this tool in stream/aquatic areas as the spatial distribution is far more confined than over a terrestrial study area?&nbsp; Lastly, I've looked through some literature and videos about this tool, but if anyone has any recommendations of something I could read/watch to understand spatial statistics and clustering better, it would be greatly appreciated.</SPAN></BODY></HTML> Thu, 12 Dec 2013 17:14:53 GMT https://community.esri.com/t5/spatial-statistics-questions/newbie-question-about-hot-spot-analysis/m-p/544155#M1765 BrettGreenfield__DNR_ 2013-12-12T17:14:53Z