Error Handling

Updating procedures

Given information up to time T, the published index values are {`P<sub>1</sub>, … , `P_T}. So when time T+1 arrives, the newly estimated index values are {`P<sub>1</sub>, … ,`P_T,`P_T+1}. Keeping all the previous index values, newly estimated index value will use the following formulae to calculate:

 

`P<sub>T+1</sub> = (`P_T+1 / `P<sub>T</sub> ) x `P_T

 

Error handling

Both programmers and users can cause errors due to improper coding or unwilling to follow instructions of the application or website constraints. It is difficult to predict errors caused by users.

 

Examples of errors may occur such as, in the gross floor area (GFA) field, instead of entering a valid GFA, the user might enter a GFA exceeding the maximum GFA within the estate. If there is no effective error handling mechanism, the user cannot gain useful information.

 

The programmers should predict the behaviour of users in advance in order to eliminate errors such as rejecting any invalid information as well as telling user that some information entered are invalid. This process is called ‘error handling’.

 

In our interactive model, we will set out necessary constraints to handle errors. For instance, the minimum and maximum floor level is 1 and 28 in Laguna City. So we will set the constraints between these two numbers. In other words, floor level which is larger than 28 is invalid and cannot proceed to property valuation.