Full Look Ahead Calculator for "On Using Linear Diophantine Equations for in-Parallel Hiding of Decision Tree Rules" - HiLDE Calculator (ver.1.9)
Hellenic Open University
School of Science and Technology
© 2017-2019

This Javascript application calculates the minimum number of positive/negative instances that have to be added to every node in order to hide Node 0.
The table bellow can be filled by the initial corresponding numbers of positive and negative instances of each node.
In order to hide Node 0, this method firstly add/subtract the appropriate number of instances to convert the node 0 to leaf. This modification will change all the ratios (p/n) of the other Nodes (1-4).
The method calculates the coefficients of the Linear Diophantine Equations which correspond to each node.
The application solves the eight Linear Diophantine Equations (two for every node).
Then the method using the set of solutions of Linear Diophantine Equations finds the minimum number of instances (positive or/and negatives) that have to be added to each node in order to maintain the corresponding ratios to their initial values.
Node 4 (root): Positive:
Negative:
Node 3: Positive:
Negative:
Node 2: Positive:
Negative:
Node 1: Positive:
Negative:
Node 0 (Node for hiding): Positive:
Negative:





Node 1 Positive:

 Negative:

 Diophantine Equations:

 General Solutions:
Node 2 Positive:

 Negative:

 Diophantine Equations:

 General Solutions:
Node 3 Positive:

 Negative:

 Diophantine Equations:

 General Solutions:
Node 4: Positive:

 Negative:

 Diophantine Equations:

 General Solutions:


The optimum path between the infinite pairs of solutions is the following: Node 4 Node 3 Node 2 Node 1
The number of Positive instances that have to be added per node are:

The number of Negative instances that have to be added per node are: