oTree help & discussion

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New resources (summer 2021):

New sample games

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5:09 PM

Data on demo version

Hi, I want to know if it is possible to access and download data from the demo version. I've

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Data on demo version

Hi, I want to know if it is possible to access and download data from the demo version. I've

5:09 PM

Jannik Greif, … Chris @ oTree6

Jul 25

Access num_participants

Also it's session.num_participants, not session.config.num_participants. Sent from my phone On

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Access num_participants

Also it's session.num_participants, not session.config.num_participants. Sent from my phone On

Jul 25

Valery Pavlov, Chris @ oTree3

Jul 25

How to make the number of players a configurable parameter?

Hi Chris, Thank you for your prompt help. Very much appreciated! Regards Valery On Sunday, July 25,

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How to make the number of players a configurable parameter?

Hi Chris, Thank you for your prompt help. Very much appreciated! Regards Valery On Sunday, July 25,

Jul 25

Dallas Novakowski, Chris @ oTree6

Jul 25

Changing forced response items to requested response

Actually this is the same mechanics as the the comprehension_test app here: https://www.otreehub.com/

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Changing forced response items to requested response

Actually this is the same mechanics as the the comprehension_test app here: https://www.otreehub.com/

Jul 25

Frederik Lau Rasmussen, Chris Crabbe6

Jul 24

Using Random to generate positions

Hey again.. Sorry for the inconvenience.. I had made a mistake in my model.BooleanField and so it was

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Using Random to generate positions

Hey again.. Sorry for the inconvenience.. I had made a mistake in my model.BooleanField and so it was

Jul 24

Vitor Freire, Chris @ oTree4

Jul 23

Error when advancing page (disable autoflush ?)

Ah ok, it makes sense, I really have an Integer field in the page A. I'll implement the solutions

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Error when advancing page (disable autoflush ?)

Ah ok, it makes sense, I really have an Integer field in the page A. I'll implement the solutions

Jul 23

Min Fang, Chris @ oTree2

Jul 23

an attribute error in class page

Hi, if you want to send me your project I can try upgrading it myself. (No guarantees depending on

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an attribute error in class page

Hi, if you want to send me your project I can try upgrading it myself. (No guarantees depending on

Jul 23

Alejandro Hirmas, Chris @ oTree2

Jul 23

Question about templates, styleblocks and

There are 3 levels of blocks: global_scripts app_scripts scripts Any scripts that are specific to the

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Question about templates, styleblocks and

There are 3 levels of blocks: global_scripts app_scripts scripts Any scripts that are specific to the

Jul 23

Qwigly Dee, Chris @ oTree2

Jul 23

New implementations of real-effort tasks

Thank you Max! I'm looking forward to hearing people's feedback on these apps. On Thursday,

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New implementations of real-effort tasks

Thank you Max! I'm looking forward to hearing people's feedback on these apps. On Thursday,

Jul 23

Diego Matheu, Max R. P. Grossmann2

Jul 23

Deploying on independent server

Hi Diego, I recommend to just use nginx as a reverse proxy instead of Apache, and to obtain a X.509

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Deploying on independent server

Hi Diego, I recommend to just use nginx as a reverse proxy instead of Apache, and to obtain a X.509

Jul 23

Katy Tabero, Chris @ oTree19

Jul 22

New timeout errors (H12) - diagnosis help

Thank you for the update! On Thursday, July 22, 2021 at 4:18:48 AM UTC-6 k.ta...@gmail.com wrote: Hi

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New timeout errors (H12) - diagnosis help

Thank you for the update! On Thursday, July 22, 2021 at 4:18:48 AM UTC-6 k.ta...@gmail.com wrote: Hi

Jul 22

Vitor Freire, Chris @ oTree2

Jul 22

How to change heroku project name and root url

click on the app here here: https://dashboard.heroku.com/apps Then go to the settings section (I

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How to change heroku project name and root url

click on the app here here: https://dashboard.heroku.com/apps Then go to the settings section (I

Jul 22

Min Fang, Chris @ oTree5

Jul 21

a problem about iterating roles while keep the id_in_group fixed

Here is what I am trying. The codes did not work and I find out that I do not know how to use the

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a problem about iterating roles while keep the id_in_group fixed

Here is what I am trying. The codes did not work and I find out that I do not know how to use the

Jul 21

Jiaqing Liu, Chris @ oTree2

Jul 21

Moving text around horizontal radio buttons

Look at the HTML source and see if there is any CSS that reposition those labels. Or maybe in the

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Moving text around horizontal radio buttons

Look at the HTML source and see if there is any CSS that reposition those labels. Or maybe in the

Jul 21

Tran Luu, Chris @ oTree3

Jul 21

Issue with object and attribute

By the way instead of player.vars you need to do: participant = player.participant participant.vars[

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Issue with object and attribute

By the way instead of player.vars you need to do: participant = player.participant participant.vars[

Jul 21

Abcde, Chris @ oTree5

Jul 21

"database connection isn't set to UTC" and Server Error (500) on otree hub

Thank you. Chris @ oTree schrieb am Mittwoch, 21. Juli 2021 um 17:23:53 UTC+2: Take a look at your

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"database connection isn't set to UTC" and Server Error (500) on otree hub

Thank you. Chris @ oTree schrieb am Mittwoch, 21. Juli 2021 um 17:23:53 UTC+2: Take a look at your

Jul 21

Chris @ oTree, Alejandro Hirmas3

Jul 21

Question about real effort tasks

Thanks! On Wednesday, July 21, 2021 at 5:29:05 AM UTC-6 janoh...@gmail.com wrote: Hi Chris! In my

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Question about real effort tasks

Thanks! On Wednesday, July 21, 2021 at 5:29:05 AM UTC-6 janoh...@gmail.com wrote: Hi Chris! In my

Jul 21

Alejandro Hirmas, Chris @ oTree2

Jul 21

Question about for loops in oTree

Instead of a dict of dicts, use a list of dicts. Sent from my phone On Jul 21, 2021, at 5:33 AM,

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Question about for loops in oTree

Instead of a dict of dicts, use a list of dicts. Sent from my phone On Jul 21, 2021, at 5:33 AM,

Jul 21

Miriam Schmidt, Chris @ oTree2

Jul 21

- Maybe try uninstalling and reinstalling oTree. Could be an incomplete installation somehow. - Don

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- Maybe try uninstalling and reinstalling oTree. Could be an incomplete installation somehow. - Don

Jul 21

Inbal, Chris @ oTree7

Jul 20

Issues with bots

Thanks, Chris! I removed it from 'cases' and then it worked fine. Best, Inbal On Mon, 19 Jul

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Issues with bots

Thanks, Chris! I removed it from 'cases' and then it worked fine. Best, Inbal On Mon, 19 Jul

Jul 20

Vitor Freire, Chris @ oTree2

Jul 19

Creating a file to be downloaded by participants

You can generate files in javaScript using the Blob object and createObjectURL. On Monday, July 19,

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Creating a file to be downloaded by participants

You can generate files in javaScript using the Blob object and createObjectURL. On Monday, July 19,

Jul 19

Abcde, Chris @ oTree9

Jul 19

Error: "ModuleNotFoundError: No module named 'websockets.extensions'; 'websockets' is not a package"

It works now. Thank you! Chris @ oTree schrieb am Montag, 19. Juli 2021 um 08:59:55 UTC+2: I'm

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Error: "ModuleNotFoundError: No module named 'websockets.extensions'; 'websockets' is not a package"

It works now. Thank you! Chris @ oTree schrieb am Montag, 19. Juli 2021 um 08:59:55 UTC+2: I'm

Jul 19

Charlie Babe, Chris @ oTree3

Jul 18

feedback for quizzes

I just added an example to otree-snippets called quiz_with_feedback: https://www.otreehub.com/

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feedback for quizzes

I just added an example to otree-snippets called quiz_with_feedback: https://www.otreehub.com/

Jul 18

Daniyal Chawla, Chris @ oTree5

Jul 16

Maximum Time on Page

This is amazing, thank you so much! On Friday, July 16, 2021 at 12:51:11 AM UTC-4 Chris @ oTree wrote

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Maximum Time on Page

This is amazing, thank you so much! On Friday, July 16, 2021 at 12:51:11 AM UTC-4 Chris @ oTree wrote

Jul 16

Chris Crabbe, … Chris @ oTree4

Jul 16

Re: [oTree] Problems with submitting forms

Your form_fields has 5 fields but I only see 4 inputs in the template. Anyway check if there is a

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Re: [oTree] Problems with submitting forms

Your form_fields has 5 fields but I only see 4 inputs in the template. Anyway check if there is a

Jul 16

Inbal, Chris @ oTree3

Jul 16

New errors when pushing code to heroku

For issue #2, simplest solution is to set the field's initial= to something other than None, for

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New errors when pushing code to heroku

For issue #2, simplest solution is to set the field's initial= to something other than None, for

Jul 16

Jul 16

Heroku Server performance issues - tips and best practices?

Hi all, I have no experience with server set-ups and am currently running an experiment on Heroku

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Heroku Server performance issues - tips and best practices?

Hi all, I have no experience with server set-ups and am currently running an experiment on Heroku

Jul 16

Shardul Vaidya, … Shardul Vaidya3

Jul 15

Large-scale Data Collection possible on oTree?

Thanks Chris! On Thursday, July 15, 2021 at 8:46:09 PM UTC+5:30 Chris @ oTree wrote: Yes use higher

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Large-scale Data Collection possible on oTree?

Thanks Chris! On Thursday, July 15, 2021 at 8:46:09 PM UTC+5:30 Chris @ oTree wrote: Yes use higher

Jul 15

Jul 15

Creating an html table with choices in vars_for_template

Just solved it! In case you are trying to do the same, update your Class to the following one: "

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Creating an html table with choices in vars_for_template

Just solved it! In case you are trying to do the same, update your Class to the following one: "

Jul 15

Alexander Laubel

Jul 15

Force subjects through pages manually

Hi everyone, so I have the following issue: I would like to show my subjects some neutral screen but

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Force subjects through pages manually

Hi everyone, so I have the following issue: I would like to show my subjects some neutral screen but

Jul 15

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