If you are using a keyboard or a mouse to collect subject responses, you are introducing delays into your response data. PST has identified a wide range of variability between devices of the same class having performed hundreds of timing tests with a variety of keyboards and mice. Sound cards are even more prone to the same variability. To eliminate this issue, PST developed the USB-based response and stimulus device, Chronos. Chronos features millisecond accuracy in the areas of stimulus, response, sound output, and external device communication. This level of timing accuracy cannot be achieved using a keyboard, mouse, or onboard sound card.
Our timing tests are performed using the Black Box Toolkit. A sample of data collected on a machine that meets the minimal requirements for E-Prime with a Windows 10 OS is summarized to the left. A more comprehensive listing of our timing data for E-Prime 3.0 and E-Prime 2.0 is on our support site. Note the performance of Chronos in comparison to a standard keyboard or mouse. In addition to millisecond accurate timing, Chronos also gives users a solution for communicating with external devices (up to 16 digital inputs and outputs) without the need for a parallel port.
To see an example of how we perform timing tests, please check out last week’s YouTube live stream! Also tune in this week to see Devon present tips on getting the best timing from your E-Prime experiment.