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DPTE Server Scheduled Downtime Thursday, Dec 11, 7:00AM – 8:00AM CST

IMPORTANT: The DPTE server will be down on Thursday, December 11 from 7:00-8:00am CST (13:00 to 14:00 UTC) to do important updates. You will be unable to run DPTE experiments during this time and logins will be disabled. It is likely the server will not be down for the entire hour, but you should avoid scheduling experiments during this window.

PLEASE NOTE: The DPTE server now has daily (recurring) maintenance at 1:55am CST (07:55 UTC). The server may be unresponsive for up to 1 minute at this time. You should avoid doing important work, and not have Subjects running Experiments, during the brief downtime.



As you may know, we had a system crash the other day. The crash appears to have been at least partly performance related: that day DPTE processed the largest number of subjects in one day ever.  As the tech staff has examined it, they’ve found some areas to fix to improve performance, so we should be in good shape going forward.

However, patches need to be applied to the server. Scheduled downtime will be between 9AM and 11AM, CDT (14:00 to 16:00 UTC) on Friday, September 20. During this time you will be unable to access DPTE or to run any subjects. Please plan accordingly.

Thanks for your patience and always feel free to let us know if you have any questions or problems.

Latest Update: DPTE V2.8.5

An update has been made to DPTE to add some new features. When you log into the system you should now be on v 2.8.5.  If you are not, then refresh your browser to clear cache.

This update includes the following:

– Owners can re-assign Experiment to another Researcher (“Owner” is now an option on the Role menu)

– Search/replace feature, which can also be used to help synchronize Subject Variable names (see DPTE faq pages for details)

– Hyperlinks and images (and other HTML) can be used in text fields (see DPTE faq pages)

– new System Variable SYS_VAR_RECORD_EVENTS can be used to turn event recording on/off. Please note if you turn off event recording you will severely limit the data you have available while recording is off.

– several Rec Data Set additions/bug fixes

We are particularly excited that hyperlinks and images are now available in text fields.  You can use HTML in the following DPTE text fields:

– A Text Stimulus Item’s main text
– an Announcement’s text
– the text of a Question.

In these fields, DPTE will treat the characters {{ and }} as < and > characters to surround your HTML. In the Player, this will render as HTML. For example, the text:

{{a href=http://www.mylink.com target=”_blank”}}Here is a link{{/a}}

would display a link to the location specified. Note that the link text will not appear underlined or blue unless you add that yourself. Remember to always include target=”_blank” so that it opens in a new window/tab.

As always, let us know if you run into any problems or have any suggestions for additional features.

DPTE Update Completed; New Features!

The DPTE update to version 2.8 (2.8.1) has been completed. If you do not see version 2.8.1 make sure your refresh your browser.

New and Updated User features of DPTE include:

Rectangular Data Set enhancements:

For multiple answer questions, the numeric number returned in the subject file is a count of how many items are selected. This is now done by the Player — the numeric answer for a Multiple Answer question is the count of answers selected, and so will be reflected in the Rec Data Set.

There have been some other incremental fixes to the rectangular datasets.

Visualization Function:

Add a visualization sheet that lists each questionnaire in the experiment (with the name of each questionnaire in its own column), and then all of the questions that are in that questionnaire in the rows below it.

Duplication Functions:

When duplicating stimuli items within an experiment, the alternatives and attributes that are assigned to that stimulus item are now carried over to the duplicate.

Language Support:

Czech language support has been added.

Player Enhancements:

Every call that DPTE can make is now tracked and reissued if it fails or does not come back with a result. The intention is to be able to recover from any state short of a prolonged outage (>30 seconds). This will probably take some further tweaking and different Experiments might yield different obstacles. This has been tested with a relatively simple experiment using a utility to “shut off” the internet for short instances, seeing if the software recovers. The major loading at the Stage and Substage breaks is tracked; apart from that, DPTE only has to load data for Questionnaires, Images, Follow-on Items, and social data (Button Click counts, and Comments). All of these are kept track of and re-issued if necessary; for example, every time the Flow Panels move, each one checks to see if it needs to reload the Button Count / Comment count data at the bottom.

The goal of these enhancements is to cut back on the number of failures of the player due to “internet lag” type problems.


As always, please test your experiments now that the revision is up, and let us know if you find any problems.


DPTE Will be Down Briefly Thursday May 2 for Upgrades

The DPTE system will be unavailable Thursday, May 2, from 10am to 10:30am CDT (11am-11:30am EDT, 15:00-15:30 UTC) for a server update. Since this is a fairly substantial update, afterwards you should test your experiments in the DPTE Player before running any larger groups of subjects, and report any inconsistencies or errors you encounter.

You will be UNABLE to run any experiments or access the experimenter interface during this time. Data for any subjects running at the time the system is taken down will be lost, so please avoid starting new subjects who will not finish before Thursday, May 2, at 10:00am CDT .

This update includes a number of new and improved features. We intend to get the user guide updated as soon as possible to include these features, including enhancements to social experiments and additional capability in the downloadable datasets.

Another Update with New Features

Our software development team at Iowa continues to work on updates and refinements to DPTE. Today we have release V2.6, which adds the following functions:

You can now create multiple-selection response options in questions by defining the question as “list box”.  For Multiple Choice this shows up as a single-select combo box menu. For a Multiple Answer a multiple-select box is available. Note that there is no default option however. If the question has not been answered it shows a s “———-” (dashes) in the box until the subject makes selections.

Questionnaires now support videos embedded in the question. The video URL is shared with the Image url right now (we assumed both wouldn’t be needed simultaneously) so you have to specify which the url applies to. This will allow you to show a video as part of a question.

Three new system variables are now available, for time spent in the experiment, stage, and substage. They are:


These are “set” when a recorded event occurs, so the times may be approximate. But normally before one checks a Condition, etc., a recorded event has just occurred (an Item being closed, or a substage beginning) so you should be able to get a good indicator of how long the subject spend in the experiment, state, and substage.

We hope these new features will be useful to many of you.

DPTE Scheduled Downtime Friday November 16

IMPORTANT: The DPTE system will be unavailable Friday, November 16, from 7:00am to 7:30am CDT (8am-8:30am EDT, 13:00-13:30 UTC) for a server update.  Please do not run subjects during this time.

The ins and outs of two DPTE studies

I just completed two studies using DPTE and thought others in the community might benefit from an account of my experiences.

The first study I completed relied on undergraduates recruited through the Purdue Psychology department’s undergraduate subject pool. My colleagues (Chris Agnew and Robert Kulzick) and I are examining whether the sequence of information people receive about potential military conflicts influences their willingness to express support for those conflicts. The point of the research is to explore differences in predictions about the dynamics of public opinion offered by rational choice and heuristic judgment theories. Briefly, rational choice theories suggest that varying the order of information people receive about potential conflicts should not make a difference to their judgments. The content of what people see or read should matter most. In contrast, Khaneman and Tversky’s work suggests that people are likely to be sensitive to information order effects.

This study ran smoothly. A number of respondents who used either the Chrome or Safari web browsers reported having trouble with the DPTE website. Those that used either Firefox or Internet Explorer were able to complete the study successfully.

The second study I completed used subjects recruited from Mechanical Turk for  research on the effects of cues about counterterrorism on anxieties about future terrorism. Once again, the study ran smoothly. We got responses from 50 people in roughly four days (we paid volunteers .25 cents for a 13 question survey). We told those that volunteered to complete the study using either Firefox or Internet Explorer and got no complaints about the DPTE website not working. We did not successfully get responses to all the questions we asked, but it looks like the problem was on our end: a number of the questions we fielded did not have values associated with the response choices and we did not end the study properly. It would have been nice to get the study done properly the first time, but if all of my mistakes only cost $12.50 I’ll be way ahead of the game.

NOTICE: Regular Downtime for Server Reset is at Midnight Eastern Time

Hi all. This post is from the software development team at the University of Iowa — the folks who have brought you the goodness that is DPTE. Please take into account when planning to run subjects, especially outside the United States, or even in the western part of the U.S.

To keep the server running smoothy we “reset” the software every night at 11pm central/12 midnight eastern time.

We chose this time so that in Europe it would be very early in the morning (4am UK) and very late here, so there would be the least chance of inconvenience, and no one would have a room full of people at those hours using DPTE. But now that people are running with MTurk, the possibility of large numbers of people running as subjects exists for just about any hour of the day, so we thought it would be useful to do this notice. The downtime only lasts for one minute, so it shouldn’t stop anyone from doing work. But if subjects are running they will all be kicked out at that time.

At the same time, this is important since implementing the “reset” seems to have cut down on the number of ‘crashes’ the server has by quite a bit. We haven’t experimented lately, but since we got a crash a few weeks ago it seems likely that if we remove the “reset” then they would become more frequent again.

We put a note on the front page of DPTE to tell people about this downtime and to contact us if it’s a bad time.

DPTE Unavailability Notice August 1, 8AM – 10AM CDT

The DPTE system will be UNAVAILABLE tomorrow, Wednesday August 1, from from 8am to 10am CDT (13:00 to 15:00 UTC) for a server and software upgrade. No authoring can be done during this window and any subjects running as of that time will be interrupted, so care should be taken to schedule accordingly.

Please do NOT plan to do any work including running subjects during this time. The downtime is to do some important upgrades that should improve performance, especially when running large numbers of subjects simultaneously. There will also be some software upgrades as we continue to roll out social experiment features.

We apologize for the inconvenience.