Stat 5411 Lab 1 Fall Assignment: Turn in copies of bike.sas and bike.lst from your SAS run. Turn this in next Friday with your assignment.

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1 Stat 5411 Lab 1 Fall 2009 Assignment: Turn in copies of bike.sas and bike.lst from your SAS run. Turn this in next Friday with your assignment. To run SAS on UMD's UNIX machine ub, you can either (1) create the commands in a file (e.g. bike.sas) and run the commands in batch mode or (2) run from within the windowed environment. The windowed environment has definite advantages but requires a computer with some windowing emulation software such as X-win32 or cygwin. The batch mode has the advantage that you can run this from any computer, even from home, by connecting to ub.d.umn.edu. For this lab SAS run will be done in a way that you could do from any location by connecting to the ub UNIX machine and using any terminal emulation software. The windowed environment requires more specialized terminal emulation, so we will start with what works from anywhere. SAS is available for Windows PC's. In many ways this is more convenient to use than the UNIX version. UM personnel can purchase SAS for a PC through a UM site license. See This is yearly price of $120 for full blown SAS. This is a really, really steep price break. For faculty and staff who use SAS, this is the usual way they buy in. If you are going to use SAS much, definitely get access to the Windows version of SAS. This is on one of the PC s in the Math/Stat computing lab for Math/Stat folks. Some other departments and faculty also have SAS. If you don t have access to the Windows version of SAS, lobby the appropriate people to get this available for you. For point and click statistical operations, my preference is SAS JMP. Others prefer Minitab, SYSTAT, but in my mind JMP is superior. In my wife's med school lab, she and the lab personnel use JMP. For more sophisticated analyses I use SAS for here data analysis. For the following instructions what you type or select is underlined and highlighted. To connect to ub on the lab machine Sign on to the Mac OS X computer with your username and password just like for . Wait for the computer screen to show the Macintosh HD icon. This can take a while. Open the Macintosh HD (hard drive). Open the Applications folder. In the Utilities Folder open the application X11 near the bottom of the utilities. If the Applications window rolls off the bottom of the screen, you may need to click the green + button in the upper left of the window. At the prompt enter ssh X username@ub and hit Return. o Use your own username, e.g. rregal, the same as your name. Enter yes when asked if you want to continue connecting. Enter your password (the same as for ) and hit Return. Enter x at the prompt asking for the terminal type. In the UMENU Unix window, scroll down to Unix near the bottom and hit Return.

2 The prompt ub.d.umn.edu1% means the computer is ready for your first command. Some of the common unix commands are described at It s best for organization of files to make a subdirectory (folder) for Use the following commands to create a directory. Commands you type will be in bold. ub.d.umn.edu1% mkdir 5411 This subdirectory or folder will be available whenever you sign on again later. To backspace, use the Delete key. To remove files or directories, use the rm command. To get info on rm or other Unix commands, look at the manual (man) page. ub.d.umn.edu3% man rm To look at the next page using more, type a space bar. Typing a q quits at that point. Manual pages are available for most of the UNIX commands. Again, basic information about UNIX commands can be found at Go to the 5411 folder that you created. To do this, you change the working directory to be 5411 so that you are working in that subdirectory. The UNIX command is cd, change directory. % cd 5411 (From here on I will use % as shorthand for the ub.d.umn.edu1% type prompt. Confirm that the working directory is 5411 by using the command pwd, print working directory. % pwd To run SAS you need a file of commands and the data. You could create command files and data files with some text editor. You can create the files directly on ub using editors such as pico or vi. The pico editor is a simple editor. I use vi which is much more powerful. has information on vi, but pico will be fine for this class. Instructions for pico can be found at For this lab I will have you use files I have already created these files. Copy the files bike.dat and bike.sas from my directory into your directory using the command cp for copy. The full UNIX path name for my directory on ub is /home/volh/14/rregal/5411. % cp /home/volh/14/rregal/5411/bike.dat bike.dat % cp /home/volh/14/rregal/5411/bike.sas bike.sas

3 In order for this to work I had to give you permission to access my 5411 subdirectory and these files. Confirm that the files were created by listing the saved files in your current working directory using the ls command to list files. % ls This lists the files that are currently saved on ub in this subdirectory. Both bike.dat and bike.sas should appear in the list using the more command. Now print the data file to the screen. % more bike.dat For a short file like this, it all fits onto one page. In general type the enter key to get the next page. Typing "q" quits right then. The data are stopping distances for bicycles with treaded and smooth tires. The data should look like treaded 365 treaded 374 treaded 376 treaded 391 treaded 401 treaded 402 smooth 341 smooth 348 smooth 349 smooth 355 smooth 375 smooth 391 Now print the file of SAS commands to the screen. % more bike.sas The file should look like /* Lab 1: Treaded and Smooth Stopping Distance */ * Ron Regal Fall 2009; libname here '. '; options linesize=80; data here.bikes; title 'Lab 1'; infile 'bike.dat'; input tire $ distance; proc sort; by tire; proc print data=here.bikes; proc univariate plots data=here.bikes;

4 var distance; by tire; proc ttest data=here.bikes; class tire; var distance; run; The semicolons are necessary. Always make sure you have semicolons in the right places. The lines and indenting are just to make the code a bit easier to read. The semicolons are the delimiters between statements. Comments are either Inserted between /*. */ Code starting with * and ending with ; The libname here associates the library name'here with the UNIX directory given within the quotes. In UNIX the dot or period represents the current directory you are using. I could use any name I feel like such as anova or junk. Alternatively, we could give the full UNIX pathway inside the quotes. libname here '/home/volh/14/rregal/5411'; SAS commands don't distinguish between upper case or lower case letters except for expressions within quotes. UNIX command do distinguish between upper and lower case letters so the command libname here '/Home/volh/14/rregal/5411'; would not work since there is no directory /Home on ub, only /home. The data here.bikes creates a permanent SAS dataset for the bikes data. This creates the file bikes.sas7bdat in your UNIX directory. This is not a file you can view with Pico for example. It is only interpretable as a SAS data set. If instead I had not used the libname before the data set name, the data set bikes would be temporary data set in a temporary library called WORK that would not exist after the sas run. data bikes; /* Creates a temporary SAS dataset called bikes */ title 'Lab 1'; etc The $ after input tire tells SAS that the tire column has alphanumeric values, not just numbers. Since distance has no $ after it, this column must be numerical. By default SAS procedures use the latest data set created. I could have just used proc print; without specifying the data set explicitly, since SAS would have used here.bikes anyway, but it's safer to specify the file. For example, if a program has an error and doesn't create the desired file, the file printed won't be the one you wanted. Even if you use data=here.bikes, you need to check the log file to make sure that the data set was successfully created; otherwise you are potentially printing an old version of the data set.

5 The print command can also be used without specifying the variables to be printed. If no variables are listed in the var command, then all variables are printed. I would have the same output in this program if I simply used proc sort; by tire; proc print; proc univariate plots; The univariate procedure produces several summary statistics and plots. by tire; means that the statistics are given separately for each tire group. In SAS whenever you do a procedure by some variable, e.g. by tire, the data must be sorted in order by that variable. The run; statement isn t necessary when using SAS in batch mode, but for the windowed use below, you need a run statement for the commands to run. Using SAS in Batch Mode To run SAS use the command % sas bike By default "sas xx" means run the commands in xx.sas Running sas creates at least one file, bike.log, and hopefully two more files, bikes.sas7bdat and bike.lst. The file bike.log has information on what happened when running bike.sas. If there were any errors, the error messages are in bike.log. Unfortunately, SAS error statements are not very clear. A common problem is to forget a semicolon delimiter, after which SAS is just confused. The error message doesn t come until the line where SAS finally finds a semicolon. An error early in the run can cascade to further errors later. Sometimes it works best to fix the first error message's problem, and then run again. Look at bike.log % more bike.log The file bike.lst has output created by the run, unless errors kept the output from being created. It's best to check the.log file before the.lst file to make sure there weren't error problems or important warnings in the run. See if the.lst file was created, list the saved files. % ls If all went well, the files bike.lst and bike.sas7bdat should be listed amongst the saved files. If bike.lst and bikes.sas7bdat are not there, fix any problems in bike.sas using pico, and rerun the commands with "sas bike". Below you will find out how to do all of this in another way. The file bike.sas7bdat is the data saved as a SAS data set. If you came back tomorrow, you could still use this data set in another program such as libname anova '. '; proc print data=anova.bikes;

6 Note that it doesn't matter what name I use for the library, e.g. anova or here; only the actual directory name in quotes matters. If all went well, the file bike.lst is listed amongst the saved files. The lst file has the results from running the SAS commands. If the.lst file is there, look at the file. % more bike.lst This file has a bunch of statistical results including summary statistics, confidence intervals and p-values. Mail a copy of the bike.sas and bike.lst files to yourself. The simplest way is to type % mail username < bike.sas % mail username < bike.lst The files will be in the body of the messages, not as attachments. You need to hand in copies of bike.sas and bike.lst. You can either print this out in the lab or elsewhere. To print the files to turn in you can either print in Mon209 or 239 (which costs) or transfer the file to print elsewhere. If you want to save paper, you can delete appropriate page feeds in the document. These are the ^L characters, control-l. You can also transfer the files to the Mac computer you are using. Here is how to do this, but for now just skip this, and go down to the Windowed instructions below. Tp transfer files to the Mac, on the Macintosh choose Lab Apps Internet Fetch (double click) (or use the doggie at bottom of the screen) File/New Connection Hostname: ub.d.umn.edu Username/Password Double click your 5411 directory which you created earlier The files bike.sas and bike.lst should be listed. Drag the bike.sa and bike.lst files to the Mac desktop. You could also yourself the bike.sas and bike.lst files as an attachment using the pine program. % pine Specify an attachment as 5411/bike.lst o If this works, the attachment name will be expanded to include the size of the file being attached.

7 Using SAS in the Windowed Environment. Make sure you are still in the subdirectory % pwd If not, changeg directories so that youja re in the same directory where you saved bike.sas. At the UNIX prompt type % sas dms The dms stands for Display Manager System. Choose Start Guide in the Getting Started Tutorial window. After a bit of a wait, a web window appears where you can choose Go for the New SAS Programmer info. Someday explore this guide. For now, close the Getting Started with SAS window. The editor window is used to enter commands just like in the bike.sas file. In this window you need to explicitly include a run statement to get SAS to run the commands. You should set options for the editing window at the top of the Program Editor window Tools/Options/Program Editor On the General tab you can select Promt to save on window close by making that square darkened. If the square is already darkened, leave it darkened. This reminds you to save the commands in a.sas file. On the Editing tab Choosing Split lines on a carriage return adds a new line of commands when you press the Enter key. Next, uncheck Clear text on submit if this is not already unchecked. This keeps command in the editor window after a submit. This makes it easier to make changes in commands after they are run. By default the editor window is in overtype mode. I prefer input mode where typing in test just pushes old test along, not replacing the old text. In Tools/ Options/Preferences/Editing choose Insert for the Cursor option if you don t want text overwritten. Have Automatically store selection unchecked to allow yourself to keep highlighted text. To copy and paste text, you need to use Edit/Copy and Edit/Paste From the editor window open the file with sas commands File/ Open/ bike.sas Change the Ron Regal part to your own name. Save the file with File/Save. On the toolbar at the top run the commands by Run/Submit

8 To see all of the windows, you may need to move the Output window. Info such as error messages appears in the SAS: Log window. Look at the log window for any problems that need to be fixed. If you did have to run another set of commands, the windows are easier to view if you clear the log window before the next run. Edit/ Clear All The output will be in a window labeled SAS: Output. You do not need to hand in another copy of bike.sas or bike.lst; just the listing requested above. You could save the output window information to a file if you want. Unlike the method used in batch, the output information is not automatically saved. Use the File/Save As Change the file name in the top box to bike.lst Keep the File Type in the bottom window as *.lst Click OK to save the file bike.lst to your UNIX account.. Or you can copy and paste for example into a Word file. When importing SAS output to Word, use Courier font (or another fixed size font) at 10pt. If you need to run the program again after fixing some command, the output window will be simpler to use if you clear it before the next run. Edit/ Clear All To exit from SAS back to the UNIX prompts in the editor window choose File/Exit If you want to sign off from ub at this time type % logout Close the X11 window by clicking the red button. Use the Apple logo at the upper left of the screen to Log Off. This ends the required parts of the lab. SAS is powerful and used many, many places from First Bank to Mayo Clinic. Learning more about SAS gives you useful as well as salable skills. You will only be suing a bit of SAS in this class, for the most part following examples I give. To learn more about SAS you can either Look at online documentation or Go through the Guides described in the OPTIONAL computer exercise for Lab 1.

9 There are SAS "certification" tests such as SAS Certification: Base Programming. Having this certification can help in getting jobs that require SAS programming but often isn t totally necessary depending on your other experience and salability. The exams cost $180 to take, but students are given 50% discounts. I have study guides for the Base and Advance Programming certification tests if you want to see them. These are useful for the basics of how SAS works even if you are not taking one of the exams. For things we do in this class, you can find information easiest at the online documentation. Go to the web site which has SAS documentation. Or you can go to my web site under Links/ SAS Documentation. To see some of the very basic info: 1. Click the + next to Base SAS Software. 2. Click the + next to SAS Language Reference: Concepts. 3. Click the + next to Data Step Concepts. 4. Double click Data Step Processing. By successively clicking the Next button, read the following sections without being concerned about all of the information making sense immediately. The execution of SAS will make more sense after you actually use SAS. Why Use a Data Step Overview of DATA Step Processing Processing a DATA Step: A Walkthrough About DATA Step Execution About Creating a SAS Data Set with a DATA Step Writing a Report with a DATA Step The Data Step and ODS 5. Double click the + next to Reading Raw Data. Red this information. 6. On left-hand side scroll down Operating Environment Specific Information. Click the + and then the + next to Running SAS Software Under UNIX Double click Getting Started with SAS in UNIX Environments Look at Starting SAS Sessions in UNIX Environments Batch Mode in UNIX Environments SAS Windowing Environment in UNIX Environment