Publications by yuwenchen
Homework_0914_ex3
Introduction Kreft and de Leeuw (1998) obtained a sub-sample of students in eighth grade from the National Education Longitudinal Study of 1988 (NELS–88) collected by the National Center for Educational Statistics of the U.S. Department of Education. The students are nested in schools. Here, we consider the following subset of the variables: s...
738 sym R (3336 sym/15 pcs) 4 img
Homework_0914_ex4
data management and graphics package library(tidyverse) ## ─ Attaching packages ───────────────────────── tidyverse 1.3.0 ─ ## ✓ ggplot2 3.3.0 ✓ purrr 0.3.4 ## ✓ tibble 3.0.1 ✓ dplyr 0.8.5 ## ✓ tidyr 1.0.2 ✓ stringr 1.4.0 ## ✓ readr 1.3.1 ✓ forcats 0.5....
111 sym R (1022 sym/9 pcs) 1 img
Homework_0914_ex5
Data management In this section, we load the exam scores data set, activate the help page for it, and examine the first 6 lines of the data frame object. # load the package to working directory library(mlmRev) # load the data from the package data(Exam, package="mlmRev") # invoke help document ?Exam # view first 6 lines head(Exam) school normex...
769 sym R (1245 sym/11 pcs) 1 img
Homework_0914_ex7
Introduction Kreft and de Leeuw (1998) obtained a sub-sample of students in eighth grade from the National Education Longitudinal Study of 1988 (NELS–88) collected by the National Center for Educational Statistics of the U.S. Department of Education. The students are nested in schools. Here, we consider the following subset of the variables: s...
738 sym R (3336 sym/15 pcs) 4 img
Homework_0921
In class exercise 1 # file location fL<-"https://math.montana.edu/shancock/data/Framingham.txt" # dta <- read.table(fL, header=T) # recode gender variable dta$sex <- factor(dta$sex, levels=c(1, 2), labels=c("M", "F")) # lattice plot library(lattice) xyplot(sbp ~ dbp | sex, data=dta, cex=.5, ty...
2478 sym R (27578 sym/106 pcs) 23 img
Homework_1005
Inclass Exercise 1 school-effects model version 0 pacman::p_load(mlmRev, tidyverse, lme4) # data from mlmRev package data(Hsb82, "mlmRev") # str(Hsb82) ## 'data.frame': 7185 obs. of 8 variables: ## $ school : Ord.factor w/ 160 levels "8367"<"8854"<..: 59 59 59 59 59 59 59 59 59 59 ... ## $ minrty : Factor w/ 2 levels "No","Yes": 1 1 1 1 ...
3799 sym R (53992 sym/123 pcs) 21 img
Homework_1019_2
Exercise 1 The new drug Novafylline is developed to reduce the symptoms of intermittent claudication, which is a medical term for pain caused by too little blood flow, usually during exercise. Patients were randomly assigned to receive either Novafylline (active treatment) or a placebo in a double-blind study. A total of 38 patients (20 for treat...
3652 sym R (11619 sym/29 pcs) 4 img
Homework_1019
In Class Exercise 1 The arrhythmogenic dose of epinephrine (ADE) is determined by infusing epinephrine into an animal until arrhythmia criterion is reached. The arrhythmia criterion was the occurrence of four intermittent or continuous premature ventricular contractions. Once the criterion has been reached, the infusion required to produce it is ...
6519 sym R (39001 sym/67 pcs) 9 img
Covariance pattern model_EMG
Data were mean electromyographic (EMG) amplitudes in the left brow region, measured over 90 seconds in response to different kind of music presented to 22 subjects. Measurements were taken while the subjects listened to each of four kinds of music: a relaxing piece, followed by pieces designed to elicit positive affect, agitation, and sadness. So...
1360 sym R (21644 sym/40 pcs) 6 img
Homework_1130_Exercise part2_1
Exercise 1 In a learning task known as a free-recall list, each subject was presented with a list of words, one at a time, for a few second each. After all the words had been presented, the subject was asked to recall as many of the words as possible. On each successive study trial the order of presenting the words differ. Control: 2 trials on Li...
1668 sym R (9849 sym/35 pcs) 10 img