Publications by Wilson Chau
Data 605 Discussion 9
Chapter 9.3 Exercise 5 Write a program to choose independently 25 numbers at random from [0, 20], compute their sum S25, and repeat this experiment 1000 times. Make a bar graph for the density of S25 and compare it with the normal approximation of Exercise 4. How good is the fit? Now do the same for the standardized sum S ∗ 25 and the average A25...
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Data_605_Week8_Reply
#Question 1 Exercise 1 Page 312 A fair coin is tossed 100 times. The expected number of heads is 50, and the standard deviation for the number of heads is (100·1/2·1/2)1/2 = 5. What does Chebyshev’s Inequality tell you about the probability that the number of heads that turn up deviates from the expected number 50 by three or more standard devi...
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Data_605_Discussion_8_Chapter_7_Sums_of_Variables
I #Chapter 7.1 Exercise 8 A baseball player is to play in the World Series. Based upon his season play, you estimate that if he comes to bat four times in a game the number of hits he will get has a distribution pX=0 1 2 3 4. .4 .2 .2 .1 .1 Assume that the player comes to bat four times in each game of the series. Question (a) Let X denote the num...
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Data_605_Discussion_7_Reply
In replying to Diana Discussion #Chapter 6.1 Exercise 1 A card is drawn at random from a deck consisting of cards numbered 2 through 10. A player wins 1 dollar if the number on the card is odd and loses 1 dollar if the number if even. What is the expected value of his winnings? I used the Probability of winning -> is drawing an even card. There are...
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Data_605_Discussion_6_Combinatroics
#Chapter 3. Combinatorics 3.2 Question 8 A die is rolled 30 times. What is the probability that a 6 turns up exactly 5 times? Since the dice is rolled 30 times we can use (1/6)^(30) P_5Sixs <- choose(30,5)/6^30 P_5Sixs ## [1] 6.446079e-19 What is the most probable number of times that a 6 will turn up? Since we get a 6 if we use (1/6)*30 (1/6) * 30...
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Intro to Data - Data 606 Week 2/3
Getting started Load packages In this lab, we will explore and visualize the data using the tidyverse suite of packages. The data can be found in the companion package for OpenIntro labs, openintro. Let’s load the packages. library(tidyverse) library(openintro) The data data(nycflights) names(nycflights) ## [1] "year" "month" "day" ...
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Data 607 04 - R Character Manipulation and Date Processing
#1. Using the 173 majors listed in fivethirtyeight.com’s College Majors dataset [https://fivethirtyeight.com/features/the-economic-guide-to-picking-a-college-major/], provide code that identifies the majors that contain either “DATA” or “STATISTICS” Finding major with the word “Data” library(stringr) Word_Data_or_Stat <-read.csv("ht...
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Data 607 Project 1
Introduction: In this project, you’re given a text file with chess tournament results where the information has some structure. Your job is to create an R Markdown file that generates a .CSV file (that could for example be imported into a SQL database) with the following information for all of the players: Player’s Name, Player’s State, Tot...
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Data 606 Lab 3
The Hot Hand Basketball players who make several baskets in succession are described as having a hot hand. Fans and players have long believed in the hot hand phenomenon, which refutes the assumption that each shot is independent of the next. However, a 1985 paper by Gilovich, Vallone, and Tversky collected evidence that contradicted this belief ...
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Data 606 assignment 4
Getting Started Load packages library(tidyverse) library(openintro) The data This week you’ll be working with fast food data. This data set contains data on 515 menu items from some of the most popular fast food restaurants worldwide. Let’s take a quick peek at the first few rows of the data. Either you can use glimpse like before, or head ...
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