Our recent study demonstrated how to capture, in JavaScript, computer screens' display change time with near-millisecond precision by taking into account the given monitors' refresh cycles (using RAF loops). For the present follow-up study, we seek upcoming regular online response-time experiments whose primary goal is to measure common psychological phenomena (such as, e.g., a Stroop effect), so that we can assess the extent of timing improvement in case of such real experimental results (e.g., a larger overall Stroop effect due to lower within-test variances). In each contributing experiment, we will implement two different timing mechanisms: (a) the inferior conventional one (with no RAF) that ignores the refresh cycle, and (b) the superior new one (with RAF) that takes refresh cycles into account and hence provides superior (more precise) results. For each display change in each experiment, the underlying code will store both timings, and thereby the experiment leaders will be able to use the superior timing data for their primary purpose for the study (e.g., estimating the Stroop effect or its modulations under given conditions), and may simply disregard the other timing data. For our project however, the aim is solely the meta-analytical comparison of the two timing mechanisms, and does not concern the studies' original purposes. Thereby each contributing study will serve two purposes at the same time, with very little extra effort (see below).
Design requirements
Technical requirements
You need to have your own JavaScript web app for data collection (not via Qualtrics or such). Then it should be easy to add to it the implementation of the new RAF timing measurements: both source code and intructions for it can be found here (but still we can help with it). For the "inferior" timing, the time should simply be called outside (before or after) the RAF call, hence simply ignoring the refresh cycle. Both timings should be saved for each relevant display change. In the end, you should use the superior timing measurement for the original purposes of your study, while on our end we will use the data from your experiment solely to compare the two timing mechanisms.
The data and information we need
At the end of the data collection for your experiment, we would ask for the following.
  1. All relevant data collected during the experiment. (If you prefer, you can exclude all data or information not related to display timing – see below for what is relevant.)
  2. A very short description of the chief effect, e.g.: "The RT difference between compatible and incompatible stimuli in a regular Stroop task."
  3. The name of the relevant RT columns: (a) display time with RAF, (b) display time with no RAF, and (c) external (keyboard/mouse) response time.
  4. The name of the column that distinguishes the two stimulus types to be compared. For example: "stim_type" column name, with "compatible" and "incompatible" types.
  5. Column names and other information necessary for filtering data, if applicable (e.g., to exclude practice data or incorrect responses).
We would also welcome but do not strictly need, from each test: browser brand and version, OS brand and version, location (the country in which the participant took the test), and the date of starting and/or finishing the task.
Your reward
For your contribution you would be offered co-authorship in our eventual paper. Your study will also be cited (and very briefly described, as provided by the authors).
The project is organized by the iScience team at the University of Konstanz (head of group: Prof. Dr. Ulf-Dietrich Reips), in collaboration with the Department of Methodology and Statistics at Tilburg University (Dr. Bennett Kleinberg).
If you are interested in contributing or have any questions, please contact Gáspár Lukács at

Last updated: September 20, 2022