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- 1. Adaptive rectangular sampling: An easy, incomplete, neighbourhood-free adaptive cluster sampling design ArchivedArticles and reports: 12-001-X201600214684Description:
This paper introduces an incomplete adaptive cluster sampling design that is easy to implement, controls the sample size well, and does not need to follow the neighbourhood. In this design, an initial sample is first selected, using one of the conventional designs. If a cell satisfies a prespecified condition, a specified radius around the cell is sampled completely. The population mean is estimated using the \pi-estimator. If all the inclusion probabilities are known, then an unbiased \pi estimator is available; if, depending on the situation, the inclusion probabilities are not known for some of the final sample units, then they are estimated. To estimate the inclusion probabilities, a biased estimator is constructed. However, the simulations show that if the sample size is large enough, the error of the inclusion probabilities is negligible, and the relative \pi-estimator is almost unbiased. This design rivals adaptive cluster sampling because it controls the final sample size and is easy to manage. It rivals adaptive two-stage sequential sampling because it considers the cluster form of the population and reduces the cost of moving across the area. Using real data on a bird population and simulations, the paper compares the design with adaptive two-stage sequential sampling. The simulations show that the design has significant efficiency in comparison with its rival.
Release date: 2016-12-20 - Articles and reports: 11-633-X2016003Description:
Large national mortality cohorts are used to estimate mortality rates for different socioeconomic and population groups, and to conduct research on environmental health. In 2008, Statistics Canada created a cohort linking the 1991 Census to mortality. The present study describes a linkage of the 2001 Census long-form questionnaire respondents aged 19 years and older to the T1 Personal Master File and the Amalgamated Mortality Database. The linkage tracks all deaths over a 10.6-year period (until the end of 2011, to date).
Release date: 2016-10-26 - 3. Statistical matching using fractional imputation ArchivedArticles and reports: 12-001-X201600114539Description:
Statistical matching is a technique for integrating two or more data sets when information available for matching records for individual participants across data sets is incomplete. Statistical matching can be viewed as a missing data problem where a researcher wants to perform a joint analysis of variables that are never jointly observed. A conditional independence assumption is often used to create imputed data for statistical matching. We consider a general approach to statistical matching using parametric fractional imputation of Kim (2011) to create imputed data under the assumption that the specified model is fully identified. The proposed method does not have a convergent EM sequence if the model is not identified. We also present variance estimators appropriate for the imputation procedure. We explain how the method applies directly to the analysis of data from split questionnaire designs and measurement error models.
Release date: 2016-06-22 - 4. A comparison between nonparametric estimators for finite population distribution functions ArchivedArticles and reports: 12-001-X201600114541Description:
In this work we compare nonparametric estimators for finite population distribution functions based on two types of fitted values: the fitted values from the well-known Kuo estimator and a modified version of them, which incorporates a nonparametric estimate for the mean regression function. For each type of fitted values we consider the corresponding model-based estimator and, after incorporating design weights, the corresponding generalized difference estimator. We show under fairly general conditions that the leading term in the model mean square error is not affected by the modification of the fitted values, even though it slows down the convergence rate for the model bias. Second order terms of the model mean square errors are difficult to obtain and will not be derived in the present paper. It remains thus an open question whether the modified fitted values bring about some benefit from the model-based perspective. We discuss also design-based properties of the estimators and propose a variance estimator for the generalized difference estimator based on the modified fitted values. Finally, we perform a simulation study. The simulation results suggest that the modified fitted values lead to a considerable reduction of the design mean square error if the sample size is small.
Release date: 2016-06-22 - Articles and reports: 11-522-X201700014750Description:
The Educational Master File (EMF) system was built to allow the analysis of educational programs in Canada. At the core of the system are administrative files that record all of the registrations to post-secondary and apprenticeship programs in Canada. New administrative files become available on an annual basis. Once a new file becomes available, a first round of processing is performed, which includes linkage to other administrative records. This linkage yields information that can improve the quality of the file, it allows further linkages to other data describing labour market outcomes, and it’s the first step in adding the file to the EMF. Once part of the EMF, information from the file can be included in cross-sectional and longitudinal projects, to study academic pathways and labour market outcomes after graduation. The EMF currently consists of data from 2005 to 2013, but it evolves as new data become available. This paper gives an overview of the mechanisms used to build the EMF, with focus on the structure of the final system and some of its analytical potential.
Release date: 2016-03-24 - Articles and reports: 11-522-X201700014755Description:
The National Children’s Study Vanguard Study was a pilot epidemiological cohort study of children and their parents. Measures were to be taken from pre-pregnancy until adulthood. The use of extant data was planned to supplement direct data collection from the respondents. Our paper outlines a strategy for cataloging and evaluating extant data sources for use with large scale longitudinal. Through our review we selected five evaluation factors to guide a researcher through available data sources including 1) relevance, 2) timeliness, 3) spatiality, 4) accessibility, and 5) accuracy.
Release date: 2016-03-24
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Articles and reports (6)
Articles and reports (6) ((6 results))
- 1. Adaptive rectangular sampling: An easy, incomplete, neighbourhood-free adaptive cluster sampling design ArchivedArticles and reports: 12-001-X201600214684Description:
This paper introduces an incomplete adaptive cluster sampling design that is easy to implement, controls the sample size well, and does not need to follow the neighbourhood. In this design, an initial sample is first selected, using one of the conventional designs. If a cell satisfies a prespecified condition, a specified radius around the cell is sampled completely. The population mean is estimated using the \pi-estimator. If all the inclusion probabilities are known, then an unbiased \pi estimator is available; if, depending on the situation, the inclusion probabilities are not known for some of the final sample units, then they are estimated. To estimate the inclusion probabilities, a biased estimator is constructed. However, the simulations show that if the sample size is large enough, the error of the inclusion probabilities is negligible, and the relative \pi-estimator is almost unbiased. This design rivals adaptive cluster sampling because it controls the final sample size and is easy to manage. It rivals adaptive two-stage sequential sampling because it considers the cluster form of the population and reduces the cost of moving across the area. Using real data on a bird population and simulations, the paper compares the design with adaptive two-stage sequential sampling. The simulations show that the design has significant efficiency in comparison with its rival.
Release date: 2016-12-20 - Articles and reports: 11-633-X2016003Description:
Large national mortality cohorts are used to estimate mortality rates for different socioeconomic and population groups, and to conduct research on environmental health. In 2008, Statistics Canada created a cohort linking the 1991 Census to mortality. The present study describes a linkage of the 2001 Census long-form questionnaire respondents aged 19 years and older to the T1 Personal Master File and the Amalgamated Mortality Database. The linkage tracks all deaths over a 10.6-year period (until the end of 2011, to date).
Release date: 2016-10-26 - 3. Statistical matching using fractional imputation ArchivedArticles and reports: 12-001-X201600114539Description:
Statistical matching is a technique for integrating two or more data sets when information available for matching records for individual participants across data sets is incomplete. Statistical matching can be viewed as a missing data problem where a researcher wants to perform a joint analysis of variables that are never jointly observed. A conditional independence assumption is often used to create imputed data for statistical matching. We consider a general approach to statistical matching using parametric fractional imputation of Kim (2011) to create imputed data under the assumption that the specified model is fully identified. The proposed method does not have a convergent EM sequence if the model is not identified. We also present variance estimators appropriate for the imputation procedure. We explain how the method applies directly to the analysis of data from split questionnaire designs and measurement error models.
Release date: 2016-06-22 - 4. A comparison between nonparametric estimators for finite population distribution functions ArchivedArticles and reports: 12-001-X201600114541Description:
In this work we compare nonparametric estimators for finite population distribution functions based on two types of fitted values: the fitted values from the well-known Kuo estimator and a modified version of them, which incorporates a nonparametric estimate for the mean regression function. For each type of fitted values we consider the corresponding model-based estimator and, after incorporating design weights, the corresponding generalized difference estimator. We show under fairly general conditions that the leading term in the model mean square error is not affected by the modification of the fitted values, even though it slows down the convergence rate for the model bias. Second order terms of the model mean square errors are difficult to obtain and will not be derived in the present paper. It remains thus an open question whether the modified fitted values bring about some benefit from the model-based perspective. We discuss also design-based properties of the estimators and propose a variance estimator for the generalized difference estimator based on the modified fitted values. Finally, we perform a simulation study. The simulation results suggest that the modified fitted values lead to a considerable reduction of the design mean square error if the sample size is small.
Release date: 2016-06-22 - Articles and reports: 11-522-X201700014750Description:
The Educational Master File (EMF) system was built to allow the analysis of educational programs in Canada. At the core of the system are administrative files that record all of the registrations to post-secondary and apprenticeship programs in Canada. New administrative files become available on an annual basis. Once a new file becomes available, a first round of processing is performed, which includes linkage to other administrative records. This linkage yields information that can improve the quality of the file, it allows further linkages to other data describing labour market outcomes, and it’s the first step in adding the file to the EMF. Once part of the EMF, information from the file can be included in cross-sectional and longitudinal projects, to study academic pathways and labour market outcomes after graduation. The EMF currently consists of data from 2005 to 2013, but it evolves as new data become available. This paper gives an overview of the mechanisms used to build the EMF, with focus on the structure of the final system and some of its analytical potential.
Release date: 2016-03-24 - Articles and reports: 11-522-X201700014755Description:
The National Children’s Study Vanguard Study was a pilot epidemiological cohort study of children and their parents. Measures were to be taken from pre-pregnancy until adulthood. The use of extant data was planned to supplement direct data collection from the respondents. Our paper outlines a strategy for cataloging and evaluating extant data sources for use with large scale longitudinal. Through our review we selected five evaluation factors to guide a researcher through available data sources including 1) relevance, 2) timeliness, 3) spatiality, 4) accessibility, and 5) accuracy.
Release date: 2016-03-24
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