Starting a Session with "Persistent Link"

[18tr17]

Hi there!

When I try to launch a session using a "persistent link," I'm prompted to enter an administrator username and password. I didn’t see any steps in the tutorial package about creating admin credentials.

Could you point me to how/where to set this up? My goal is to distribute a single persistent link to participants to run this study.

Thank you,
Tara

[Howquez]

Hi Tara,

Thank you for your question about persistent links. You are correct that the web interface prompts for administrator credentials when you try to access persistent links, and I understand this creates an obstacle for your study setup.

Short answer: The web interface does not currently provide access to persistent links without administrator credentials. However, I am working on a solution that will give you a persistent link with an ID you can match between the DICE data and Qualtrics. I will post an update soon.

In the meantime, let me explain how the available links work, as one of them might serve your needs until the persistent link solution is ready.

When you create a session and click "View Session," you see three types of links:

Session-wide link (e.g., https://ibt-hsg.herokuapp.com/join/mekozami): The first person who clicks this link takes the role of P1 and occupies the first single-use link. The second person becomes P2 and occupies the next link. This continues for as many participants as you created in your database. The key limitation is that if the same person clicks the session-wide link again, the system treats them as a new participant because it cannot distinguish between users.

Single-use links (e.g., https://ibt-hsg.herokuapp.com/InitializeParticipant/pjhy5eoz): Each link corresponds to one participant role. If you click the example link above, you take the role of P1 with participant code pjhy5eoz. This code appears in your data, so you can match it to the emails you sent or other records. However, this code does not pass to Qualtrics automatically (I am fixing this issue).

For a lab session where you want to avoid the complications of the session-wide link, you can distribute individual single-use links to each participant. Each person clicks their unique link, and you can track them via the participant code in your DICE data (not yet in the Qualtrics data though).

Note on Prolific integration: The Prolific URL you create in the DICE App (which includes parameters like {{%PROLIFIC_PID%}}) ensures that one Prolific ID can only occupy one single-use link. This prevents the double-assignment problem but requires Prolific's system.

Alternative if you need full control now: You can download the oTree code and host it yourself on Heroku (instructions here: https://otree.readthedocs.io/en/latest/server/heroku.html). This gives you access to create rooms with persistent links directly.
I will update you as soon as the persistent link solution is ready for the web interface

Hope this helps,
Hauke

[Howquez]

Hi Tara,

I worked on a solution that lets you distribute single-use links to your participants and track the same unique ID in both DICE and Qualtrics data.

To set this up, select Lab Study as your Study Type and configure it. When you create the session, you'll see additional instructions. These tell you to click View Session to retrieve your single-use links. Each link follows this syntax: https://ibt-hsg.herokuapp.com/InitializeParticipant/[unique ID created by oTree]. DICE stores this ID as participant_code in your data and forwards it to Qualtrics as a URL parameter.

You'll need to configure Qualtrics to capture this URL parameter by adding an embedded data field (see here). Once you complete this step, DICE and Qualtrics will share the same unique ID for each participant.

Hope this helps!