Publications by Mircea Dumitru
Statistical Inference: Power, Multiple Comparisons & Resampling - Week 4
Question 1 A pharmaceutical company is interested in testing a potential blood pressure lowering medication. Their first examination considers only subjects that received the medication at baseline then two weeks later. The data are as follows (SBP in mmHg): Subject Baseline Week 2 1 140 132 2 138 135 3 150 151 4 148 146 5 135 130 Consider t...
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Statistical Inference: Assignment 1
Part 1: Simulation Exercise Instructions 1. Show the sample mean and compare it to the theoretical mean of the distribution Consider \(n\) random variables \(X_1, \ldots, X_n\), following an Exponential distribution with rate parameter \(\lambda\): \[ X_{1} \sim \text{exponential}(x \mid \lambda) \] The corresponding mean \(\mu\) and variance \(\s...
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Statistical Inference: Assignment 2
Part 2: Basic Inferential Data Analysis Instructions Now in the second portion of the project, we’re going to analyze the ToothGrowth data in the R datasets package. 1. Load the ToothGrowth data and perform some basic exploratory data analyses. library(datasets) data("ToothGrowth") 2. Provide a basic summary of the data. summary(ToothGrowth) ##...
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Statistical Inference: Variability, Distributions, Limits, & Confidence Intervals - Week 2
Module 5: Variability One important characterization of a population is how spread out it is. One key measure of spread is variance, measured with the sample variance, or the standard deviation. The standard deviation has the same units as the population (different from the variance). The variance is itself an intrinsically interesting quantity th...
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Statistical Inference: Probability & Expected Values - Quiz 1
Question 1 Consider influenza epidemics for two parent heterosexual families. Suppose that the probability is \(17\%\) that at least one of the parents has contracted the disease. The probability that the father has contracted influenza is \(12\%\) while the probability that both the mother and father have contracted the disease is \(6\%\). What is...
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Statistical Inference: Variability, Distributions, Limits, & Confidence Intervals - Quiz 2
Question 1 What is the variance of the distribution of the average an draw of \(n\) observations from a population with mean \(\mu\) and variance \(\sigma^2\) Answer 1 \[ \frac{\sigma^2}{n} \] Question 2 Suppose that diastolic blood pressures (DBPs) for men aged 35-44 are normally distributed with a mean of 80 (mm Hg) and a standard deviation of ...
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Document
Synopsis The U.S. National Oceanic and Atmospheric Administration’s (NOAA) storm database tracks characteristics of major storms and weather events in the United States, including when and where they occur, as well as estimates of any fatalities, injuries, and property damage. The data is used in this project for descriptive statistics: determi...
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