A web -based free software application for online and offline A web -based free software application for online and offline A web -based free software application for online and offline A web -based free software application for online and offline experiments on primingexperiments on primingexperiments on primingexperiments on priming

Pablo Garaizar, Miguel A. Vadillo, & Helena MatutePablo Garaizar, Miguel A. Vadillo, & Helena MatutePablo Garaizar, Miguel A. Vadillo, & Helena MatuteUniversidad de Deusto (Bilbao, Spain)Universidad de Deusto (Bilbao, Spain)Universidad de Deusto (Bilbao, Spain)

“Libprime” is a fully customizable free software application Software Architecture“Libprime” is a fully customizable free software applicationdesigned for online and offline research on priming. This effect has

Software Architecturedesigned for online and offline research on priming. This effect hasbeen previously demonstrated in many computer-assisted Labprime design is based on three basic principles: modularity,been previously demonstrated in many computer-assisted Labprime design is based on three basic principles: modularity,been previously demonstrated in many computer-assistedexperiments with humans (Ratcliff & McKoon, 1978; Fazio, 2001)

Labprime design is based on three basic principles: modularity,customization and standards compliance. Its loosely coupled layerexperiments with humans (Ratcliff & McKoon, 1978; Fazio, 2001)

but most of them have been done offline. Considering thecustomization and standards compliance. Its loosely coupled layerarchitecture allows concurrent work of researchers, developers andbut most of them have been done offline. Considering the architecture allows concurrent work of researchers, developers andbut most of them have been done offline. Considering the

enormous potential of the Internet as a source of experimentalarchitecture allows concurrent work of researchers, developers anddesigners, detaching feature configuration from application’s codeenormous potential of the Internet as a source of experimental

subjects, we have developed a World Wide Web Consortiumdesigners, detaching feature configuration from application’s codeand hiding technical issues to researchers in a “program once,subjects, we have developed a World Wide Web Consortium and hiding technical issues to researchers in a “program once,subjects, we have developed a World Wide Web Consortium

(W3C) standard compliant application (XHTML, CSS, JavaScript)and hiding technical issues to researchers in a “program once,experiment many” approach. The application’s performance can be(W3C) standard compliant application (XHTML, CSS, JavaScript)

suitable for online and offline experimentation. This application hasexperiment many” approach. The application’s performance can beimproved without reprogramming it, updating used libraries (e.g.suitable for online and offline experimentation. This application has improved without reprogramming it, updating used libraries (e.g.suitable for online and offline experimentation. This application has

been released as Free Software –GPLv3 (Smith, 2007)– and isimproved without reprogramming it, updating used libraries (e.g.jQuery 1.4) or running on an optimized JavaScript engine (e.g.been released as Free Software –GPLv3 (Smith, 2007)– and is

available for download at our research group websitejQuery 1.4) or running on an optimized JavaScript engine (e.g.Google Chrome’s V8). Appearance can be themed easily by aavailable for download at our research group website Google Chrome’s V8). Appearance can be themed easily by aavailable for download at our research group website

(www.labpsico.deusto.es).Google Chrome’s V8). Appearance can be themed easily by adesigner using Cascading Style Sheets (CSS). Experimental(www.labpsico.deusto.es). designer using Cascading Style Sheets (CSS). Experimentalsubjects are allowed to use any standards compliant browser.subjects are allowed to use any standards compliant browser.

Figure 1. Software Architecture of the application. Figure 1. Software Architecture of the application. Figure 1. Software Architecture of the application. Researchers can edit several versions of global Researchers can edit several versions of global

configuration and messages files. Experimental core and configuration and messages files. Experimental core and internationalization support rely on jQuery based libraries. internationalization support rely on jQuery based libraries.

Timers are provided by the native JavaScript API.Timers are provided by the native JavaScript API.

ResultsResults

Labprime is a lightweight and multiplatform solution for priming experimentation. As we can see in Figure 2, most of the settings involved in aLabprime is a lightweight and multiplatform solution for priming experimentation. As we can see in Figure 2, most of the settings involved in apriming experiment can be set up editing fully commented plain text files. Several browser/OS combinations have been proved with minorpriming experiment can be set up editing fully commented plain text files. Several browser/OS combinations have been proved with minorpriming experiment can be set up editing fully commented plain text files. Several browser/OS combinations have been proved with minorappearance differences and no functionality loss (see Figure 3 for a screenshot of Labprime running an affective priming experiment)..appearance differences and no functionality loss (see Figure 3 for a screenshot of Labprime running an affective priming experiment)..

Figure 2. Labprime’s main • Online / offline versions.• Server-side (PHP, ASP) and email based data collection.General

Figure 2. Labprime’s main features. Every feature can be

Google Chrome 5.0 on Windows XP.

Discussion ReferencesDiscussion References

Client-side technologies provide better precision and accuracy Eichstaedt, J. (2001). An inaccurate-timing filter for reaction time measurement by JAVAClient-side technologies provide better precision and accuracymeasuring response times than server-side approaches. Java or

Eichstaedt, J. (2001). An inaccurate-timing filter for reaction time measurement by JAVAapplets implementing Internet-based experiments. Behavior Research Methods,measuring response times than server-side approaches. Java or

Flash have been preferred over JavaScript (Eichstaedt, 2001;

applets implementing Internet-based experiments. Behavior Research Methods,Instruments, & Computers 2001, 33 (2), 179-186.

Flash have been preferred over JavaScript (Eichstaedt, 2001;Instruments, & Computers 2001, 33 (2), 179-186.

Fazio, R. (2001). On the automatic activation of associated evaluations: an overview.Flash have been preferred over JavaScript (Eichstaedt, 2001;Reimers & Stewart, 2007), but recent studies (Galesic et al., 2007)

Fazio, R. (2001). On the automatic activation of associated evaluations: an overview.Cognition and Emotion, 2001, 15(2), 115-141.Reimers & Stewart, 2007), but recent studies (Galesic et al., 2007)

confirm the reliability of the measurements obtained usingCognition and Emotion, 2001, 15(2), 115-141.

Galesic, M., Reips, U., Kaczmirek, L., Czienskowski, U., Liske, N., & von Oertzen, T.confirm the reliability of the measurements obtained using Galesic, M., Reips, U., Kaczmirek, L., Czienskowski, U., Liske, N., & von Oertzen, T.(2007, September). Response Time Measurements in the Lab and on the Web: A

confirm the reliability of the measurements obtained usingJavaScript-based experimental tasks for most of the cases.

(2007, September). Response Time Measurements in the Lab and on the Web: AComparison. Paper presented at the 10th Congress of the Swiss Society ofJavaScript-based experimental tasks for most of the cases.

Another noticeable advantage of using a client-side approach isComparison. Paper presented at the 10th Congress of the Swiss Society ofPsychology. Differences, Diversity, and Change, Zurich.Another noticeable advantage of using a client-side approach is Psychology. Differences, Diversity, and Change, Zurich.Another noticeable advantage of using a client-side approach is

the ability to deploy identical offline and online versions, with very Ratcliff, R., & McKoon, G. (1978). Priming in item recognition: Evidence for thethe ability to deploy identical offline and online versions, with verylow computational requirements.

Ratcliff, R., & McKoon, G. (1978). Priming in item recognition: Evidence for thepropositional structure of sentences. Journal of Verbal Learning and Verbal

low computational requirements.propositional structure of sentences. Journal of Verbal Learning and VerbalBehavior, 17, 403-417.low computational requirements. Behavior, 17, 403-417.

Reimers, S. & Stewart, N. (2007). Adobe Flash as a medium for online experimentation: A

Finally, the license and standard-compliant nature of LabprimeReimers, S. & Stewart, N. (2007). Adobe Flash as a medium for online experimentation: A

test of reaction time measurement capabilities. Behavior Research Methods 2007,Finally, the license and standard-compliant nature of Labprime test of reaction time measurement capabilities. Behavior Research Methods 2007,39 (3), 365-370.

enable the collaborative improvement of its main features by other39 (3), 365-370.

Smith, B. (2007). A Quick Guide to GPLv3. Free Software Foundation, Inc. Online:enable the collaborative improvement of its main features by otherresearch groups or third-party developers.

Smith, B. (2007). A Quick Guide to GPLv3. Free Software Foundation, Inc. Online:http://www.gnu.org/licenses/quick-guide-gplv3.html. Referred 4.3.2010.research groups or third-party developers. http://www.gnu.org/licenses/quick-guide-gplv3.html. Referred 4.3.2010.

GOR 2010GOR 2010GOR 2010General Online ResearchGeneral Online Research

Laboratorio de Psicología ExperimentalMay 26-28, 2010, University of Pforzheim

Laboratorio de Psicología ExperimentalExperimental Psychology Laboratory May 26-28, 2010, University of Pforzheim Experimental Psychology Laboratory