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- Some words from the instructor
- Source of data sets and examples
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- Some of materials were copied/modified from course materials of Biostatistics, M.P.H. program at Vanderbilt University, and the course textbook, "Statistical Modeling for Biomedical Researchers", 2nd Ed.,
*in press*, by William Dupont. [WD] refers to William Dupont's book

- enter a dataset displayed in Table 4.1
- assign the data description
- make a note which documents the source of the data and the date of creation
- label each variable
- use
`codebook`

,`describe`

, and`summarize`

- save the commends that used so far in the review window as do file

- download Haemoglobin and use
`infile`

command to import the data:`infile id hemo using "C:\Teaching\IGP\data\haemoglobin.txt", clear`

- make a box plot : go to Stata pulldown menus --> Graphics --> Box plots, choose
*hemo*in the box called "Variables" - observe what appears in the review window

- see
`help axis_options`

- make Fig. 3.8: put a main title and a subtitle (name them whatever you want) using
`title`

and`subtitle`

- make Fig. 3.9: put the x title, add the x tick marks to the x-axis from 7 to 11 in units of 1, and add the x minor tick marks to the x-axis at 7.5, 8.5, 9.5, 10.5
- make Fig. 3.10-3.11: put x and y axis labels and tick marks, and put the main, x and y axis titles
- make Fig. 3.12: put a main title and the y axis title

- Use Haemoglobin in Table 3.2:
- calculate the mean and standard deviation for haemoglobin using the code provided in Stata notes for classes [EMS] Chapter 4.
- compare the results with the output using
`summarize`

- Stata Lab: calculate the following values using the code provided in Stata notes for classes [EMS] Chapter 5
- find the area in upper tail of the standard normal distribution for
**_z = 1.975_** - find the area in lower tail of the standard normal distribution for
**_z = -1.95_** - find the area of the standard normal distribution between two values,
**_z = -1_**and**_z = 1_** - find the area of the standard normal distribution between two values,
**_z = -2.58_**and**_z = 2.58_**

- find the area in upper tail of the standard normal distribution for

- R Lab: The purpose of this lab is to examine how the standard deviation of a population and the sample size of a trial affect the standard errors using the code provided in R notes [EMS] Chapter 4.
- download R 2.4 official site and open R
- open a text editor
- copy the code to the text editor
- change the values of the s.d of the population
**_sigma_**and the number of observation in each sample,**n**e.g.`sigma <- 20`

,`n <- 5`

in R - copy the modified code and paste to R (do not copy the whole commands; copy several lines at each time)
- observe how the standard errors change as function of
**_sigma_**and**n**

- Generate ANOVA Table 9.1 (c) using the code provided in Stata notes for classes [EMS] Chapter 9
- then calculate F value

- Reproduce the tables on Chapter 10 using the code provided in Stata notes for classes [EMS] Chapter 10
- Draw a scatter plot with the estimated linear regression line and 95% confidence band

Topic revision: r20 - 05 Feb 2007, LeenaChoi

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