Abstract
Recovering data points from scanned or photocopied graphs by hand is time consuming, prone to error, and it requires patience and a steady hand. An alternative is to use g3data—a program that reads many common image file types and allows accurate estimation of data point coordinates from the graphs contained in these files. Limits of the software are discussed, and validation of its accuracy using graphs with known data values is presented.
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The authors have no relationship, financial or otherwise, with Jonas Frantz, the creator of the g3data software. g3data is free software released under the GNU General Public License. The present research was supported, in part, by a Natural Sciences and Engineering Research Council of Canada (NSERC) Discovery Grant to M.R.
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Bauer, B., Reynolds, M. Recovering data from scanned graphs: Performance of Frantz’s g3data software. Behavior Research Methods 40, 858–868 (2008). https://doi.org/10.3758/BRM.40.3.858
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DOI: https://doi.org/10.3758/BRM.40.3.858