Reese's GIS Expedition

     This week, in the fifth Special Topics in Geographic Science lab, was about Interpolation with concerns to surfaces.     This lab was broken into two parts, the first half had us comparing Spline and IDW Interpolations to each other and the second half had us analyzing water quality with different interpolations.           With the first half, we were introduced to Spline and how to use it properly while also comparing it to IDW/DEM interpolation. Once we had produced the Spline, we then subtracted it with the Raster Calculator tool from IDW in order to see the differences between the two. What we saw was areas that were more negative were more aligned to IDW but areas that were more positive where aligned to Spline. This was in part because of the elevation differences between the two Interpolation methods and their variance on the points they came from. This is especially true for areas where they were equal, which causes a d...

     This week, in the fourth Special Topics in Geographic Science lab, was about TINs and DEMs with concerns to surfaces.        In this lab, we focused mainly on preforming correct analysis of layers onto a 3D spaces, as well as the visualization of the data they can provide. An example of this can be seen below, as after viewing and exploring TINs on a terrain surface, we then made a suitability map for ski runs. This involved a lot of process in changing our raster to a TIN, Slope, and Aspect, before reclassifying them all and putting them together. In doing so, we gave the inclines their own value in order to then show the steeper the slope the more suitable it would be for skiing.      After doing that, we then explored and made our own TINs. This was a helpful application as the symbology for TINs is very mailable, with points, aspect, edges, and slope. This was immensely helpful as what we did earlier with spatial analy...

     This week, in the third Special Topics in Geographic Science lab, was about assessment with concerns to data quality.       In this lab, we did an assessment on road lengths in Jackson county Oregon. This was done in order to give us more experience with assessing the accuracy with concerns to road length data. As you will see in the the map below we had taken the full lengths of our road files, Tiger and Centerlines in order to preform a percent difference evaluation between them. With the full lengths between the two road lengths being Tiger Roads with 11,382.7 kilometer and Street Centerlines with 10,805.8 kilometers.       As for how we got the map, we did some analysis. So, to start I used the clip tool to obtain both road lengths contained within the provided grid. This trimmed out any toads that had left the grid so all the data could remain within the grid. Next, since my data for the road lengths was alr...

     This week, in the second Special Topics in Geographic Science lab, was about standards with concerns to data quality.       In this lab, we made an accuracy assessment of two road networks, one from Streetmap USA and the other from the City of Albuquerque. To start, we added our shapefiles to our map that you see below of both our road networks. With them, we then made a good few test points where the roads intersect, as you can see in the map, in order to preform our accuracy assessment.       Once done, we then added more detailed imagery to the map so that we could change 20 or so of our test points into actual reference points. When doing so, we placed these reference points where we believed was the exact center of the intersections. Once we had our 20 points, we then went back and placed our Streetmaps USA and City of Albuquerque points where they displayed the corresponding intersections in their shapefiles. With a total...

    This week, in the first Special Topics in Geographic Science lab, was about Fundamentals of data accuracy and precision.      In this classes lab we preformed analysis on a GPS data in order to determine how precise and accurate our data was to the reference points. As you can see in the map below we used the points given to make an average point which we used to make a precision buffer of 50, 68 and 90 percentiles. The 68 percentile is what we use for the majority of the lab but it does later lie close horizontally to our reference point.       For my horizontal accuracy, the distance was 3.25 m. For the horizontal precision, we got 4.4 m. Between these two sets of data we know that out data is accurate with as our reference points lies within out horizontal precision, but due to the rest of our waypoints being farther away from each other does mean our precision is lacking.      Why this is is because with accuracy, ...

     This week,  in the sixth Applications in GIS lab, was about  Suitability Analysis.     In this lab we utilized more of our skills with ArcGIS to do sustainability analysis on a study area in Oregon. In the first part of the lab it was us attempting to do analysis to find where there would be possible mountain lion habitats within the study area. Although it will not be presented within this blog, the analysis proved a good warmup for the map we will be presenting.     In the map below, you will see a suitability analysis of the study area with concerns to property development. This analysis first started with reclassifying land cover with ratings from 1 to 5. The desirable areas are labeled 5, like agriculture and meadows, while the lower end is 1 with urban and rivers. Following this, we did the same to soils after changing it from a polygon to a raster. For Soils we also rated it 1 to 5. Moving on, we also did the same for elevation af...