Using BCR
Gordon Pitz, Department of Psychology, UNC Chapel Hill
BCR is a convenient way to develop student projects, but it is not suitable for everyone. The advantage to BCR is that you can create a fairly complicated procedure, and automate the data collection process. Its disadvantage is that you will need to spend some time learning how to use it. If your project is quite simple, and could be implemented using a pencil-and-paper questionnaire or a PowerPoint presentation, it may not be worth taking the time to learn about BCR. If you want to measure reaction times, coordinate stimulus presentations carefully, or use responses more complicated than questionnaires, BCR may be essential.
A sample BCR file, BCRDemo.bce, illustrates the kind of experimental operations that can be programmed with BCR. Run this experiment to get an idea how your own experiment might be designed. It illustrates the stimuli, responses, and other features that can be controlled with BCR.
Download the necessary software and install it on your own computer. You should also download some sample experiments that will help you learn to use BCR.
You do not need any programming experience to use BCR. However, you should have a clear idea of the experiment you want to develop for your project. You should also be comfortable with translating ideas into working computer applications (preparing a spreadsheet might be a good example).
Here is a Checklist that you should follow carefully. Make sure you understand all of the steps needed to create an experiment and have it run properly.
Download BCR and run the experiment file BCRDemos - It illustrates all of the features that are available. Decide which ones you need for your experiment.
To create an experiment, run BCR and from the main panel click on the "Designer" button. To see how the Designer works, look at the built-in demonstration. Click on "Designer" and then choose "Introduction to the Designer". Follow the instructions.
To learn how to use BCR you should examine one or more of the tutorials. Click on "Designer", and choose "Load and review tutorial". Start with "Tutorial No. 1", then review "Tutorial No. 2". The third tutorial covers some advanced topics that you may not need. You may also want to review one or more of the sample experiments. Start with the "RT Demo" sample. This is a fairly simple and straightforward experiment, and is a good supplement to the tutorials.
BCR Help files
If you are using Windows Vista or Windows 7, you may be unable to open BCR help files. You will need to install WinHlp32.exe for Windows Vista or Windows 7.
You can find the necessary files, and information about installing them, at the Windows support center.
You will need to make arrangements to have your own experiment installed on the P: drive. In the P:\BCR folder, there is a sub-folder called "PROJECTS". A folder for your experiment will be created under P:\BCR\PROJECTS. For example, if your project is called "JANE", a folder called P:\BCR\PROJECTS\JANE will be created for your project.
Caution: Do not try to create this folder yourself. BCR will not recognize it unless the necessary information has been entered by an administrator. Contact your course instructor.
You should copy your program and other materials to this folder. Be sure that all the stimulus files you need—bitmap image lists, jpg files, sound or video files—are placed in this folder (see Checklist, step 7). When you or your subjects run the experiment, instead of selecting a section number, you and they should select "PROJECTS". Then choose the project name from the list of projects that will be displayed. All your data will be saved in the folder.
Unfortunately all student project folders will be accessible to all students in the course. To prevent loss of your experiment and data, be sure to keep backups of your experiment, and copy the data to your own computer as soon as you can after running the experiment.
To set up your own space on the P: drive, or to obtain more information about BCR, or if you have questions about how to use BCR for your own project, contact your course instructor. If you have completed the first two tutorials and still have questions about using BCR, contact me at pitz@unc.edu.
Five Common Mistakes
[The symptoms that indicate the mistake, and where to read about it in the Checklist]
- Failing to establish a project folder correctly.
[Your project does not save the data correclty on the P: drive: Step 2]- Misunderstanding the concept of Trial Stage.
[You end up with eight or more trial stages in a block of trials, and a very inefficient design: Step 4]- Failing to remove the file path from stimulus files.
[Your stimulus files fail to work properly from the P: drive: Step 7]- Failing to consider data analysis needs.
[The project is over and you don't know what to do with the data: Step 8]- Including unnecessary raw data in the aggregate data file.
[A data file that is incomprehensible: Step 8]