Publications by Chris Callaghan
Homework 1
1 Question 1 1.1 Background A researcher is studying the effects of sonar on marine mammals, specifically cetaceans. Reports of whale beachings from the Bahamas to the Canary Islands have been associated with navy sonar exercises but no real evidence has been provided to show a link between the two activities. Our researcher’s first of many st...
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Statistical Methods for Two or More Variables
There are two types of tests for statistically analyzing your data, parametric and nonparametric. Strictly speaking, parametric test assumes specific parameters about the distribution of the population from which the data are drawn. On the other hand, non-parametric tests do not make those assumptions. Table 1 below (which originally appeared her...
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Hypothesis Testing
What is hypothesis testing used for? Background Hypothesis testing is a formal process for validating research assumptions made about a population. Here the researcher is trying to say something using quantitative analysis. However, since making assertions about an entire population require impractical, expensive, or simply impossible data colle...
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Basics of Descriptive Statistics and Probability Theory
1. Explain when one would use Bayesian probability. Before we can explain Bayesian probability, perhaps we should backtrack a little and deal with conditional probability, which is simply the probability of an event occuring given that another event has taken occurred. This is to say, the probability of one event is dependent on the occurrence of...
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Short Assignment
Explain what the four data types (levels of measurements) are and provide simple examples to illustrate these levels. Note: Since I am rather uncreative, I leveraged my knowledge of commonly used open source data sets to use as an example. Here, I proceed using the mtcars data, which comprises a series of variables on 32 automobiles (1973-74 mo...
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Population Density
Setting Up The population data used here comes from the American Community Survey, Demographics and Housing Estimates for 2019, accessible here. In order to calculate the density, the area for census tracts will be required, luckily, these data can be found here. This documentation was written in R and I used the following supplementary libraries...
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