A Beautiful Union: How to merge data on SPSS

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You’ve just spent hours finding the perfect data for your project. The problem now is that you have two (or more) different data sets and you need to smoosh them all into one. Here is how you can do that:

YouTube video: California State University, ITS Training Program

1. First, the two data sets you want to merge need to have a common, unique identifier (key variable) for each case in your data set. Both data files should provide different data for the same set of cases. Also, make sure the cases are spelled exactly the same and are in the same order in both data sets (You could try sorting them in ascending order before trying to merge).

2. Open the first file that you wish to merge. Under the “Merge Files” item in the Data menu, select “Add Variables”

3. Select the file you wish to merge

4. If the cases have the same name one will show up in the “Excluded Variables” list. This will be the common variable that you will use to merge the data files together. If your key variables have different names you should rename one so they both have the same name. Select the key variable from the “Excluded Variables” list and check the “Match cases on key variables in sorted files” checkbox. Then send the variable to the key variables box (using the arrow pointing to the right).

5. Click OK. SPSS will give you a warning regarding sorted key variables. If everything is in order (make sure both files have key variables that are spelled the same and are sorted in order before trying to do a file merge) click OK again. All variables from both files will be merged in a new datafile, and cases are matched by the key variable.

As always, ask a consultant for help if you get lost!

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“Can I get a copy of that stats program?”

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The simple answer to this question: It depends!

It depends not on whether you can repay us with delicious treats for our service (kidding, kidding), but on the type of software you want and if you are a student or faculty member. The three kinds of statistical software on demand for distribution are SAS, SPSS, and STATA. Here is our general policy on software distribution:

SAS

  • We can distribute SAS to both students and faculty on either a personal or AU-owned computer.

SPSS

  • We do not distribute SPSS to students. Students who want to own a copy of SPSS on their personal computer must purchase the software online. You could also download a trial version of SPSS for a limited time use.
  • We can distribute SPSS to staff and faculty as long as the computer is AU-owned.

STATA

  • We do not distribute STATA to students. If you would like your own copy of STATA, you must purchase it online.
  • We can help you install STATA if you are staff or faculty and as long as your computer is AU-owned.

*AU-owned computer means that you have a computer or laptop that was distributed to you by American University.

For more information on additional software supported by our lab that we can or cannot distribute, visit out website to learn about statistical packages such as R, EViews, and alternative open source software.

Remember, all of these programs are installed on our lab computers where you can access them for FREE and even get FREE help if you have trouble using them. If you still have questions about the kinds of software our lab is able to distribute, please do not hesitate to ask a consultant.

Why Lynda can be your best friend

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Have you met our good friend Lynda? Her face is one you can’t miss…she sort of looks like MTV’s cartoon character Daria with her best friend Jane’s haircut. She can help you learn most of the leading software out there to enhance your skills for that job you want to land or that term project to you want to ace.

Lynda.com includes a collection of online video tutorials on how to use various software. The tutorials range from beginner level to showing more advanced features of the product. The video clips are generally short, usually between 2 and 10 minutes. And because they are videos, you can stop and go back at anytime to hear the instructor repeat the lesson. Unfortunately, Lynda.com doesn’t cover any statistical packages.

As an American University student or faculty member, you have free access to Lynda.com’s services online. Just log into your my.american.edu account >> Technology >> Web-based software training library. Some of the featured software that we do support in the lab that is found on Lynda.com are Dreamweaver and Excel (many of the media and design programs are supported by New Media Center, also located in Hurst). But don’t stop there! Make Lynda your best friend and learn a software you never knew before!

Google Earth Pro now available in Hurst lab

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pinpoint Google Earth Pro

The Hurst lab gained a new addition to the family of supported software! Google Earth Pro, an upgraded version of the traditional Google Earth, is now available as a specialty program on one of our machines. Just look for the monitor labeled Google Earth Pro – that will be the only computer with the software installed.

The Pro version includes all of the same functions that regular Google Earth has, such as the satellite imagery database, the ability to explore any point on the planet or space, and the ability to search for buildings, streets, and parks. You will also find the tools to rotate and tilt the view in 3D or draw on your map on both versions.

It is different from Google Earth in four main ways:

1. High-resolution capability:
Google Earth Pro uses the same imagery database as the free version, so there are no changes to the locations you see in Google Earth Pro. However, with Google Earth Pro, you can print these locations at a higher resolution. You can save images in 1400, 2400, and 4800 pixels.

2. Includes GIS data input tools:
Import point, lines and path, and polygon vector data.

3. Area measurement:
In addition to measuring with a line or a path, you can measure with a circle radius or polygon. This is handy for finding the area of nontraditional shapes and sizes.

4. Movie maker:
You can use the Movie Maker feature of Google Earth to record 3D viewer imagery and save the recording as a movie file. You can either set the recorder to record your interactions with the 3D viewer in real-time, or you can set up a tour and record the entire tour without interruption.

Google Earth Pro is generally used for commercial use by NGOs and businesses, and now it is available to the students and faculty at AU. Grab the world by the click of a mouse and check out Google Earth in our lab. Regular Google Earth is also available on all the computers in the Hurst and SPA labs.

4 Stats Apps for your iPhone or iPad

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StatsMate screenshot

Do you ever wish that you could carry a whole bunch of databases and statistics in your pocket?  These days you can, thanks to these four apps that you can download for your iPhone or iPad.

An important note – SSRL does not endorse any of these apps, nor will we be able to show you how to use them.  Also, these apps are not ranked in order of coolness, and they have not been tested by the consultants. The descriptions below come directly from the app description on iTunes, where you can get even more information about the app.

1. StatsMate

StatsMate (screenshot above) allows you to search for a statistical value without interpreting a table. StatsMate is created to help you find probability density curves areas, critical values, rejection regions of hypothesis testing, P-values, and more. It features many of the common probability distributions, including the normal, chi-square, gamma, and many others.  This app is available for both the iPhone and iPad. You can try the lite version for free.

2. OECD Factbook

Wherever you are, you can get easy access to a comprehensive statistical picture of the world’s major economies from OECD. The app is organized around12 themes such as population and migration, macroeconomic trends, and globalization. Each indicator includes a table showing the latest available data for the 30 OECD countries. This app is free but not available on the iPad.

3. World Bank Data Finder

This app lets you access fifty years of World Bank data on more than 1,100 global economic indicators for around 200 countries, chart and visualize that data, and share those data and charts for use in you presentations and projects. This app is free for both the iPhone and iPad.

4. Economy for iPad

This app gives you a snapshot of the U.S. Economy (and also individual states) by providing the latest key economic indicators and tracking the history of these indicators across the past few months, years, and decades. It features the latest values of key U.S. economic indicators (GDP, Employment, Housing, Manufacturing, Infliation, etc) published by the U.S. Federal Reserve. This app is only available for the iPad.

If you decide to try any of these apps yourself, let us know if they are useful to you!

Things to keep in mind while using SPSS

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When using SPSS, you’ll quickly find that there are few conventions unique to this software, especially when it comes to naming variables and recognizing your files after you’ve saved them. Here are a few things to keep in mind when using SPSS:

File name extension:
Data files are given a “.sav” extension while output files are given a “.spv” extension. If you open an output file to launch SPSS, it will open an empty data file with it.  You will need your data to continue working on your output file. Make sure you save both your data and your output files!

Variable names:
Variable names are limited to 8 characters. SPSS won’t allow you to use characters such as !,@,#,&, etc. You can use an underscore (_) but no spaces. Also, make sure when you name your variable it is recognizable. It will save you from being confused later.

Importing from Excel:
A neat feature on SPSS is that you can import data from an Excel spreadsheet onto SPSS. When doing so, make sure you search for the file with the “.xls” extension.

Output files:
You can copy the output you’ve generated from your data by simply clicking the table or chart, copying, and pasting it in another application.  You can also print a portion of your analysis from the output file by highlighting the specific portion of the file that you want to print.

Sorting variables:
Don’t forget that when you are performing an analysis, you can sort your variables alphabetically by variable name or label name by right clicking on the variables. This will save you a lot of time when searching for the variables you want!

 

The importance of the G:/ drive

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G drive access

How to access your G:/ drive from home

G is a letter of great importance to you. It’s not a letter grade (thank goodness), but it could save you as you work hard to make the grade you want.

When you work on any of the computers in our labs, it is vital that you save your work in a place that you can go back to you when you need it. The computers in our lab completely “refresh” after you log off, meaning that whatever you save to the computer (like to the Desktop, for instance), will disappear. The best way to save your work is to bring a USB flash drive or to save it on your G:/ drive. When you log into the network on campus, you’ll find the G:/ drive in My Computer.

So today you decided to work at home in your jammies instead of bracing the winter cold to get to campus. We totally sympathize. Did you know that you can you can still access the work that you’ve done on campus from home? You can, as long as you save your work on the G:/ drive on the network. Each student has a G:/ drive to access from home or from campus. Think of it as having a USB flash drive that you never have to carry and won’t get lost!

When you want to access it from home, log into your account on my.american.edu and select the “Technology” tab on the right hand side. Under “Personalized Links”, click on”Access My Network Drive”. You will be asked to enter your log-in information again, and voila, there you will find your G:/ drive and all the work that you’ve done.

Ask a consultant if you have any questions!

 

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