Stat 133, Fall 2009Short assignment 8: Function optimizationDue Tuesday Dec. 8 at 11 pm on bSpaceThe Del Norte Salamander (plethodon elongates) is a small (57 cm) salamander found among rockrubble, rock outcrops and moss-covered talus in a narrow range of northwest California. To studythe habitat characteristics of the species, researchers selected 47 sites from plausible salamanderhabitat in national forest and parkland. Randomly chosen grid points were searched for the presenceof a site with suitable rocky habitat. At each suitable site, a 7 meter by 7 meter search area wasexamined for the number of salamanders it contained. The dataset for this assignment containsthe counts of salamanders at the sites, along with the percentage of forest canopy and age of theforest in years.1. Load the data into R, and make a scatterplot of the salamander counts against the percentcanopy cover.2. Since the data consist of counts, with no preset upper bound, we will use Poisson regressionto fit the data. Specifically, we’ll model the mean
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