Data-Purpose Algebra: Modeling Data Usage Policies

Lalana Kagal

Decentralized Information Group
MIT Computer Science and Artificial Intelligence Laboratory


Our Approach

TAMI: Transparent Accountable Datamining Initiative

Case Study: Privacy Act(5 USC § 552a)

  • Part of the Privacy Act
  • "Data collected about US citizens can be used only for the purposes for which it was collected"
TAMI usecase

What is Data Purpose Algebra (DPA) ?

Data Purpose Algebra

What does DPA do ?

How does it work?

Unary Process

  • Agent: a'
  • Data item: i
  • Content: Qd(i)
  • Category: Kd(i)
  • Source: Ad(i)
  • Purpose/Use: Pd(i)
  • New purpose/use: function of (Pd(i), Ad(i), a', Kd(i))
  • Possible to have other attributes of data
Unary Process

Binary Process

  • Agent: a''
  • Two data item: i and j
  • Content: Qd(i) and Qd(j)
  • Category: Kd(i) and Kd(j)
  • Purpose/Use: Pd(i) and Pd(j)
  • New purpose/use: function of (Pd(i), Pd(j), Ad(i), Ad(j), a'', Kd(i), Kd(j))
Binary Process

Example Formalization: Privacy Act

Modeling the Privacy Act

Modeling the Privacy Act (cont)

When information is put into a SOR (collected), or moved from one SOR to another (shared), its uses can be computed as

  • Purposes of data item in SOR
  • Purposes
  • Applicable Routine uses
  • Routine Uses
  • Authorized purposes
  • Authorized Purposes
  • New authorized purposes
  • Purposes
  • New data item
  • New data item

Implementation Details

  • DPA: Scheme
  • SORs, SORNs: RDF
  • Transaction data/Audit trail: RDF
TAMI Architecture

Background & Future Work

Related Work

Future Work



More information

Creative Commons License