Mediator - determining the group opinion

Project Status Experts Options Decisions Results Details About Mediator

Determining the group opinion

The Mediator application is the computer decision support system where the main attention is focused on one of the group work problem aspects, i.e. on the problem of determining the group opinion. During the organized internet session the experts present their judgements on topics under consideration, e.g. options of the development strategy, options of the investment policy, choice of the actions to be taken in the anticipated emergency. These experts should be gathered, the set of options must be prepared, the internet session should be organized and, at last, the group opinion should be determined.  The tool that does all this is the Mediator application and the user of this tool will be called the moderator or the project administrator.

Each problem processed by Mediator is called Project and the unique name is assigned to it. Several projects at the different stage of progress can exist in the Mediator data base. Usually, if not deleted, there exists a Demo project which is just an example. It can be used by the moderator in the learning session.

The starting window of the application is a login window. After successful login, the Mediator project window appears and the moderator can open an existing project or create a new one.


The Project combo-box of the project window is populated with the names of all projects present in the Mediator data base. When this combo-box is empty, the data base should be installed (press the Install Data Base button). The demo project is always created during the installation of the data base. The moderator can create a new project, open or delete the existing one (be careful, deleted project can not be recovered). Changed or deleted demo project can be restored (press the Restore Demo Project button). The project window image is presented below.

 When the moderator clicks the Open or Create buttons the Mediator project window is closed and application displays the main Mediator window with several pages. The main Mediator window contains several pages used on different stages of project processing. The pages are listed below:

At all the main window pages there are two common buttons: Save and Exit. The Save button allows, at any application stage, to save all changes made by the moderator to the Mediator data base.


The Status page is the starting page of the Mediator main window. It is the control page of the project. In the Leading method combo-box the moderator can choose the leading method (algorithm) determining  the group opinion. There are seven different algorithms available at present:

The results of the leading algorithm calculations will be considered as the results in force - the remaining ones will be treated as reference only.

The project can be in the one of three stages.

In the first stage the moderator processes (adds, updates, deletes) experts and options using Experts and Options pages. When this is done s/he can go to the Ordering variants stage (pressing the next stage button). The Options ordering stage is the experts internet session. The moderator can only monitor the session progress using the Decisions page. S/He waits until all experts take their decisions. Then s/he can go to the last stage, Determining the group opinion. At this stage s/he can examine results using the Results and Details pages.

There is Options ordering group of controls on the Status page containing two dates, Start date and Finish date. These are starting and finishing dates of experts session. The start date is determined by the application (when changing state to Options ordering),  but the moderator can change the Finish date.


On the Experts page the moderator can process experts data. The experts records can be added to, updated in and deleted from the Mediator data base. However, this can be done only at the first project stage (Lists of experts and options). Each expert record contains four pieces of data:

The  Login and Password fields are later used by experts to login to the Options ordering application during the internet session. The moderator can also send e-mails to the choosen experts, in particular to all of them (e.g. he can inform them that the internet session started).


This page enables adding and removing option records. The option record is quite simple and is composed of:

The option name is additionally displayed with the sequence number. In that manner the similar names are more strongly distinguished. Description file name is the 'html' type file with detailed option description. It can be viewed by experts and may be helpful in options comparison. The file name can be preceeded by the relative file path reflecting its position in the directory tree. In order to add a option the moderator must enter the new  Option name and the corresponding File name and then press the Add button. The Delete button removes the selected option from the data base and Edit button starts the 'html' type file editor enabling changes in the description file. The options can be changed only during the Lists of experts and options stage.


The Decisions page is useful only during the Options ordering stage, i. e. during the experts internet session. Until the expert taking part in the internet session does not finally order the project options, his/her Status is displayed as Not arranged and displayed Option order is in the initial sequence. For experts who have taken their decision, the ordered sequence of options approved by them is displayed when the expert is selected. An option regarded by an expert as the best one is placed in the first position,  the worst one is placed in the last position. The options not separated by the empty line are assigned to the same position.

When all experts got the Arranged status the Mediator can return to the Status page and change the project state to Determining the group opinion. The application then calculates results of all group opinion determining algorithms and the results are displayed on the Results and Details pages.


The order of project options presented at the Results page is calculateded by the group opinion determining algorithm. The applied algorithm is specified on the Status page  Leading method . The bar charts located to the left of the option name display the number of experts that placed this option in the first, the second and further positions. The positions are distinguished by different colors (from green for the first position, through blue, to red for the last position).

When a new option is selected, the detailed description of the selected option appears. When the selection changes, the description of the previous option is moved to the lower window. In that manner technical (or other) details of the two options can be compared. The selection of the same option for the second time causes the display of the short instruction visible on the image below (in the higher window).


The Details page shows results of all algorithms used to determine the group opinion.

 About Mediator

Mediator - determining the group opinion
Version: 1.0
Developed in the framwork of TransCat project

Authors: Dariusz Wagner, Hanna Bury, Tomasz Purzycki, Marek Kurowski, Andrzej Ziolkowski

Contact: Andrzej Ziolkowski