Michelle Simard Joint UNECE/Eurostat Work Session on Statistical Data Confidentiality Tarragona, Spain, November 23 rd, 2011 Progress on Real Time Remote Access

19/02/2016 Statistics Canada Statistique Canada 2 Since 2009  Developed a Prototype offering tabulated counts  Developed Statistical Disclosure Control (SDC)  Continued development on different fronts

19/02/2016 Statistics Canada Statistique Canada 3 The Prototype

19/02/2016 Statistics Canada Statistique Canada 4  Spring 2010  Tabular(counts) outputs only - SAS only  Modified PROC FREQ, Data steps  Limited to particular household surveys data sets  Confidentiality automated, no manual intervention  Limited to some Canadian Federal Departments only  Ability to query RTRA micro data at any time  Access from any computer with internet access, using a secure username and password  No travel to Research Data Centres The Prototype

19/02/2016 Statistics Canada Statistique Canada 5  Minimum 4 minutes plus process time  Maximum 3 hours plus process time  notification for outputs with 7-day retention  Formatted table in HTML or in SAS The Prototype

19/02/2016 Statistics Canada Statistique Canada 6 Additive and Controlled Rounding (ACROUND) Create rounded additive table close to original table with controlled grand total → semi-controlled rounding Use an iterative process to improve the semi- controlled result → controlled rounding Protects against possible matching of information with PUMF and small impact on precision Maximum : 5 dimensions Current SDC

7 Proc Percentile Release the percentile only if 1.there are at least n 1 observations ≥ the percentile value and at least n 2 observations ≤ the percentile value 2.it is ≠ minimum or maximum value 3.the total number of unweighted observations is ≥ m 4.the rounded frequency associated (from ACROUND) with the percentile is ≠ 0 Statistics Canada Statistique Canada 19/02/2016 Recent Development

8 Proc Mean Release the mean only if 1.there are at least n 3 observations present in the domain 2.the rounded frequency associated with the mean (from ACROUND) is ≠ 0 For both PROC, “magnitude” rounding will be applied on statistics to balance precision and noise Statistics Canada Statistique Canada 19/02/2016 Recent Development

 Not only balancing confidentiality and precision BUT quality measures as well  Evaluating the risk  Displaying information (What and How) Statistics, Standard Error(SE), Variance, Coefficient of Variation (CV), Confidence Interval (CI),Quality Indicator (QI), weighted counts, unweighted counts, ACROUND outputs? 19/02/2016 Statistics Canada Statistique Canada 9 Challenges and Issues

10 Value of CV* Quality Indicator Guideline 0 ≤ C.V. ≤ 0.10(a)very good 0.10 < C.V. ≤ 0.20(b)acceptable 0.20 < C.V. ≤ 0.35(c)marginal C.V. > 0.35(d)very poor Quality Measures  Release estimate with SE and a Quality Indicator (QI)  If not releasable ==> put ‘X’s or other symbol  otherwise release SE and QI as follows: *Note: CV is calculated from original non-rounded S.E. and percentile Statistics Canada Statistique Canada 19/02/2016

Statistics Canada Statistique Canada 11 Next steps  Used output control techniques rather than input control techniques  Next step: proportions, ratios, totals, models  May need input control techniques when going into modeling  Expansion to the academic community  Expansion to Censuses, then administrative data  Streamlining the approval processes  Developing a “fee” structure and “penalty” processes

19/02/2016 Statistics Canada Statistique Canada 12 THANK YOU  For more information,  Pour plus d’information, please contact:veuillez contacter : Michelle Simard