User Authentication
Because the Web is a medium which can be accessed from just about anywhere at any time, there has to be a way to ensure that the person evaluating a course at the client end is in fact one of the students enrolled in that particular course. It is also important to ensure that no student is able to evaluate a course or teacher more than once.
In COSSET, students are asked to log-on using thier own system usernames and passwords with the assurance that these would be stripped from the system after initial identification had been made and in no way could they be matched to the response data.
It is important to emphasis that, although students have to log on using information relating to their identifies, their anonymity is maintained because the system was designed in such a way as to make it all but impossible to trace the identity of any student making a particular response. This was a critical aspect of the design of COSSET and was repeatedly emphasised to the students.
Response Rate
In a paper-based system, the questionnaire
survey was often conducted in class time. This usually guarantees
a response rate of roughly 60%. However with an on-line system, students
are encouraged to do the evaluation in their own time. It thus becomes
hard to predict the rate of response. To encourage a reasonable response
rate, we decided to use email to remind students to do the evaluation.
System Level
COSSET is a centrally controlled Web-based system
for conducting summative end-of-semester student evaluation of teaching.
The WWW server is an Apache 1.2. It is linked to a database server, running
Sybase 11.0.3.2, which acts as the back-end database engine. Programs
called CGI scripts written in Perl run at the WWW server which dynamically
generate Web forms using information stored in the back-end database. These
forms are then displayed on the WWW clients. When the evaluation is completed,
the data is transmitted back to the WWW server which then stores them in
the back-end database. Communication between the WWW server and the database
server is accomplished using Syperl scripts.
Click here to view the System Design of COSSET.
For the purpose of system maintenance, a front-end tool was created using Microsoft Access. This system is a user-friendly menu-driven system which enables the system administrator to do regular maintenance without the need for programming.
Here will show the Data Flow Diagrams of COSSET.
Here is the Structure Chart.
Here is the Event Diagram.
Here is the Entity Relationship
Model.