# PREDICT 401 Assignment 1 V1 2015 02 08 Essay

3252 Words14 Pages
Assignment #1 Daniel Case INTRODUCTION Abalone populations are an economic and recreational resource that is threatened by a variety of factors, which include pollution, disease, loss of habitat, predation, commercial harvesting, sport fishing, and illegal harvesting. As a result of the aforementioned factors, abalone populations have declined considerably, pushing some abalone species to the verge of extinction. To help curb over harvesting and better protect abalone populations, it is important for biologists to efficiently and quickly determine the age composition of a regional abalone population. The purpose of this report is to examine the data from an observational study of abalone in Tanzania. The intent of the…show more content…
Assuming the abalone data from which this sample was drawn were randomly selected, we can be 95% confident that the true value of the population proportion is within the below confidence internals (Table 2.1). Table 2.1 PROPORTION OF MALE, FEMALE, AND INFANT ABALONE, INCLUDES 95% CONFIDENCE INTERVAL (‘Sample Data’ is a simple random sample of n=500 from original abalone sample of n=4,141) Sex Sample Data (n=500) Original Abalone Sample (n=4,141) Count Proportion 95% CI Count Proportion Male n=190 0.380 (0.339, 0.423) n=1516 0.366 Female n=157 0.314 (0.275, 0.356) n=1301 0.314 Infant n=153 0.306 (0.267, 0.348) n=1324 0.320 Abalone Volume, Density, and Weight Two additional variables (Volume and Density) were created from the dataset’s original observational variables. The data variable, volume, is a product of multiplying abalone length, diameter, and height. Similarly, the data variable, density, is a product of dividing abalone weight (i.e. the variable ‘whole’) by volume. The three likely independent data variables to predict abalone age are volume, density, and weight. As such, these three variables were examined in further detail. Charts 2.1-2.3 show each variable’s histogram and