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Leon Willenborg Contributions to a methodology of computer aided questionnaire design (DCC 37)
Engels | 62 pagina's | Netherlands Central Bureau of Statistics, Department of Statistical Methods, Voorburg | 1986
Gedrukt boek
Leon Willenborg Two characterizations of the routing structure in a questionnaire
balance and complexity (DCC 27)
Engels | Netherlands Central Bureau of Statistics, Department of Statistical Methods, Heerlen | 1986
Gedrukt boek
C.A.W. Citteur | J.R. Nobel | Leon Willenborg Privacybescherming en statistiek
Non-fictie
Nederlands | CBS, Voorburg | 1996
Gedrukt boek
Leon Willenborg Heuristieken voor het toewijzen van adressen aan interviewers (Axls 3)
Non-fictie
Nederlands | 14 pagina's | Centraal Bureau voor de Statistiek, Heerlen | 2001
Gedrukt boek
Leon Willenborg Ideeën voor Axls, een adres-interviewer matching systeem
Non-fictie
Nederlands | 15 pagina's | Centraal Bureau voor de Statistiek, Heerlen | 2001
Gedrukt boek
José Gouweleeuw | Leon Willenborg | Peter-Paul de Wolf Een kennismaking met PRAM voor het OVG
In deze nota wordt een korte introductie gegeven in de beveiligingsmethode PRAM, in het bijzonder met betrekking tot de beveiliging van het OVG. Aan de hand van een voorbeeld wordt de methode uitgelegd en worden de effecten van deze methode toegelicht. Ook de beveiligingsaspecten met betrekking tot het OVG worden besproken. Trefwoorden: Beveiliging ; OVG ; PRAM ; Spontane herkenning
Non-fictie
Nederlands | 5 pagina's | Centraal Bureau voor de Statistiek, Voorburg | 1997
Gedrukt boek
J.W.P.F. Kardaun | Leon Willenborg Cryptography as a tool to expand communications and ease of access
The higher awareness of the public and%5Egovenunents of the vulnerability of large data collections, have - at least in the Netherlands - given rise to increased requirements for the security measures of governmental data bases. Normally, stronger security measures are associated with more difficult and cumbersome access, and an increased burden for the legitimate users of data. Cryptographic techniques can be used however, to realize new ways of access and communication with the same or higher...
Non-fictie
Engels | 9 pagina's | CBS, Statistics Netherlands, Voorburg | 1999
Gedrukt boek
Jean-Pierre Kent | Leon Willenborg Documenting questionnaires
Non-fictie
Engels | 8 pagina's | CBS, Voorburg | 1997
Gedrukt boek
Leon Willenborg Establishment of a Joint Group on Statistical Disclosure Control
a proposal
Non-fictie
Engels | 4 pagina's | CBS, Voorburg | 1996
Gedrukt boek
Leon Willenborg Some improvements for →m⇋-ARGUS
In this paper we discuss several ways to increase the efficiency of m-ARGUS or the security of the data involved when using the package. M-ARGUS is intended for producing safe microdata sets. A first suggestion for improving the efficiency of m-ARGUS concerns the use of an (internal) coding scheme instead of the standard (numerical) codes one comes across in a microdata file. This is not only space saving, but it also allows m-ARGUS to deal with numerical and alphanumerical codes alike. When such...
Non-fictie
Engels | CBS, Voorburg | 1996
Gedrukt boek
Leon Willenborg | J.W.P.F. Kardaun Fingerprints in microdata sets
The paper discusses a method - referred to as fingerprinting - that is used to find the "risky" records in a microdata set. The intuition on which the method rests is that records with many short unique combinations (in the file) of values of key variables are potentially dangerous, and should be identified for further processing. Identifying the risky records in a microdata set is the aim of fingerprinting. Once the risky records with (some of) their fingerprints have been identified, appropriate...
Non-fictie
Engels | 10 pagina's | CBS, Voorburg | 1999
Gedrukt boek
P. Kooiman | Leon Willenborg | José Gouweleeuw PRAM: a method for disclosure limitation of microdata
This paper describes the Post Randomisation Method (PRAM) as a method for disclosure protection of microdata. PRAM means that for each record in the data file according to a specified probability mechanism the score on a number of variables is changed. Since this probability mechanism is known, the characteristics of the latent true data can unbiasedly be estimated from the observed data moments in the perturbed file. In this paper, PRAM is applied to categorical variables. It is shown that both...
Non-fictie
Engels | 19 pagina's | CBS, Voorburg | 1997
Gedrukt boek
A.G. de Waal | Leon Willenborg SDC measures and information loss for microdata sets
Non-fictie
Engels | 15 pagina's | CBS, Voorburg | 1996
Gedrukt boek
A.G. de Waal | A.J. Hundepool | Leon Willenborg ARGUS: software for statistical disclosure control of microdata
In recent years Statistics Netherlands has developed a prototype version of a software package, ARGUS, to protect microdata files against statistical disclosure. In 1995 the present prototype version of ARGUS, namely version 1.1, has been released. In this paper both the rules, based on checking low-dimensional combinations of values of so-called identifying variables, and the techniques, global recoding and local suppression, applied by Statistics Netherlands to protect microdata sets are described....
Non-fictie
Engels | CBS, Voorburg | 1996
Gedrukt boek
Leon Willenborg | Ardo van den Hout Possibilities of PRAM to protect statistical data
The Post Randomization Method (PRAM) is a technique to protect statistical data through perturbation of categorical variables. The paper is intended to give a nontechnical description of PRAM, its possibilities and limitations. In particular attention is devoted to two important issues, namely how to apply PRAM to protect a microdata set efficiently and what statistical implications there are when analysts have to work with a PRAM-ed data set. Key words: Statistical data protection ; Perturbation...
Non-fictie
Engels | 8 pagina's | CBS, Voorburg | 2000
Gedrukt boek
Leon Willenborg OR in statistical disclosure control
Non-fictie
Engels | 25 pagina's | CBS, Voorburg | 1996
Gedrukt boek
Leon Willenborg Optimization models for PRAM matrices
In this paper several optimization models are formulated to arrive at nonsingular PRAM matrices. Such, matrices can be used to modify a microdata set by the perturbation method for categorical variables called the Post Randomization Method (PRAM). Part of the paper is devoted to suitable (linear) criteria for assessing the safety of a PRAM-ed microdata set. The non-singularity of the resulting PRAM matrices is obtained by requiring the matrices to be dominant diagonal. Furthermore different objectives...
Non-fictie
Engels | 19 pagina's | CBS, Voorburg | 1999
Gedrukt boek