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Description:

The context of the discussion is the increasing incidence of international surveys, of which one is the International Tobacco Control (ITC) Policy Evaluation Project, which began in 2002. The ITC country surveys are longitudinal, and their aim is to evaluate the effects of policy measures being introduced in various countries under the WHO Framework Convention on Tobacco Control. The challenges of organization, data collection and analysis in international surveys are reviewed and illustrated. Analysis is an increasingly important part of the motivation for large scale cross-cultural surveys. The fundamental challenge for analysis is to discern the real response (or lack of response) to policy change, separating it from the effects of data collection mode, differential non-response, external events, time-in-sample, culture, and language. Two problems relevant to statistical analysis are discussed. The first problem is the question of when and how to analyze pooled data from several countries, in order to strengthen conclusions which might be generally valid. While in some cases this seems to be straightforward, there are differing opinions on the extent to which pooling is possible and reasonable. It is suggested that for formal comparisons, random effects models are of conceptual use. The second problem is to find models of measurement across cultures and data collection modes which will enable calibration of continuous, binary and ordinal responses, and produce comparisons from which extraneous effects have been removed. It is noted that hierarchical models provide a natural way of relaxing requirements of model invariance across groups.

Description:

Dependent interviewing (DI) is used in many longitudinal surveys to "feed forward" data from one wave to the next. Though it is a promising technique which has been demonstrated to enhance data quality in certain respects, relatively little is known about how it is actually administered in the field. This research seeks to address this issue through behavior coding. Various styles of DI were employed in the English Longitudinal Study of Ageing (ELSA) in January, 2006, and recordings were made of pilot field interviews. These recordings were analysed to determine whether the questions (particularly the DI aspects) were administered appropriately and to explore the respondent's reaction to the fed-forward data. Of particular interest was whether respondents confirmed or challenged the previously-reported information, whether the prior wave data came into play when respondents were providing their current-wave answers, and how any discrepancies were negotiated by the interviewer and respondent. Also of interest was to examine the effectiveness of various styles of DI. For example, in some cases the prior wave data was brought forward and respondents were asked to explicitly confirm it; in other cases the previous data was read and respondents were asked if the situation was still the same. Results indicate varying levels of compliance in terms of initial question-reading, and suggest that some styles of DI may be more effective than others.

Description:

In longitudinal surveys nonresponse often occurs in a pattern that is not monotone. We consider estimation of time-dependent means under the assumption that the nonresponse mechanism is last-value-dependent. Since the last value itself may be missing when nonresponse is nonmonotone, the nonresponse mechanism under consideration is nonignorable. We propose an imputation method by first deriving some regression imputation models according to the nonresponse mechanism and then applying nonparametric regression imputation. We assume that the longitudinal data follow a Markov chain with finite second-order moments. No other assumption is imposed on the joint distribution of longitudinal data and their nonresponse indicators. A bootstrap method is applied for variance estimation. Some simulation results and an example concerning the Current Employment Survey are presented.

Description:

Sample weights can be calibrated to reflect the known population totals of a set of auxiliary variables. Predictors of finite population totals calculated using these weights have low bias if these variables are related to the variable of interest, but can have high variance if too many auxiliary variables are used. This article develops an "adaptive calibration" approach, where the auxiliary variables to be used in weighting are selected using sample data. Adaptively calibrated estimators are shown to have lower mean squared error and better coverage properties than non-adaptive estimators in many cases.

Description:

We propose a method for estimating the variance of estimators of changes over time, a method that takes account of all the components of these estimators: the sampling design, treatment of non-response, treatment of large companies, correlation of non-response from one wave to another, the effect of using a panel, robustification, and calibration using a ratio estimator. This method, which serves to determine the confidence intervals of changes over time, is then applied to the Swiss survey of value added.

Description:

The analysis of stratified multistage sample data requires the use of design information such as stratum and primary sampling unit (PSU) identifiers, or associated replicate weights, in variance estimation. In some public release data files, such design information is masked as an effort to avoid their disclosure risk and yet to allow the user to obtain valid variance estimation. For example, in area surveys with a limited number of PSUs, the original PSUs are split or/and recombined to construct pseudo-PSUs with swapped second or subsequent stage sampling units. Such PSU masking methods, however, obviously distort the clustering structure of the sample design, yielding biased variance estimates possibly with certain systematic patterns between two variance estimates from the unmasked and masked PSU identifiers. Some of the previous work observed patterns in the ratio of the masked and unmasked variance estimates when plotted against the unmasked design effect. This paper investigates the effect of PSU masking on variance estimates under cluster sampling regarding various aspects including the clustering structure and the degree of masking. Also, we seek a PSU masking strategy through swapping of subsequent stage sampling units that helps reduce the resulting biases of the variance estimates. For illustration, we used data from the National Health Interview Survey (NHIS) with some artificial modification. The proposed strategy performs very well in reducing the biases of variance estimates. Both theory and empirical results indicate that the effect of PSU masking on variance estimates is modest with minimal swapping of subsequent stage sampling units. The proposed masking strategy has been applied to the 2003-2004 National Health and Nutrition Examination Survey (NHANES) data release.

Description:

The design of a stratified simple random sample without replacement from a finite population deals with two main issues: the definition of a rule to partition the population into strata, and the allocation of sampling units in the selected strata. This article examines a tree-based strategy which plans to approach jointly these issues when the survey is multipurpose and multivariate information, quantitative or qualitative, is available. Strata are formed through a hierarchical divisive algorithm that selects finer and finer partitions by minimizing, at each step, the sample allocation required to achieve the precision levels set for each surveyed variable. In this way, large numbers of constraints can be satisfied without drastically increasing the sample size, and also without discarding variables selected for stratification or diminishing the number of their class intervals. Furthermore, the algorithm tends not to define empty or almost empty strata, thus avoiding the need for strata collapsing aggregations. The procedure was applied to redesign the Italian Farm Structure Survey. The results indicate that the gain in efficiency held using our strategy is nontrivial. For a given sample size, this procedure achieves the required precision by exploiting a number of strata which is usually a very small fraction of the number of strata available when combining all possible classes from any of the covariates.

Description:

Optimum stratification is the method of choosing the best boundaries that make strata internally homogeneous, given some sample allocation. In order to make the strata internally homogenous, the strata should be constructed in such a way that the strata variances for the characteristic under study be as small as possible. This could be achieved effectively by having the distribution of the main study variable known and create strata by cutting the range of the distribution at suitable points. If the frequency distribution of the study variable is unknown, it may be approximated from the past experience or some prior knowledge obtained at a recent study. In this paper the problem of finding Optimum Strata Boundaries (OSB) is considered as the problem of determining Optimum Strata Widths (OSW). The problem is formulated as a Mathematical Programming Problem (MPP), which minimizes the variance of the estimated population parameter under Neyman allocation subject to the restriction that sum of the widths of all the strata is equal to the total range of the distribution. The distributions of the study variable are considered as continuous with Triangular and Standard Normal density functions. The formulated MPPs, which turn out to be multistage decision problems, can then be solved using dynamic programming technique proposed by Bühler and Deutler (1975). Numerical examples are presented to illustrate the computational details. The results obtained are also compared with the method of Dalenius and Hodges (1959) with an example of normal distribution.

Description:

This paper considers the optimum allocation in multivariate stratified sampling as a nonlinear matrix optimisation of integers. As a particular case, a nonlinear problem of the multi-objective optimisation of integers is studied. A full detailed example including some of proposed techniques is provided at the end of the work.

Description:

The present work illustrates a sampling strategy useful for obtaining planned sample size for domains belonging to different partitions of the population and in order to guarantee the sampling errors of domain estimates be lower than given thresholds. The sampling strategy that covers the multivariate multi-domain case is useful when the overall sample size is bounded and consequently the standard solution of using a stratified sample with the strata given by cross-classification of variables defining the different partitions is not feasible since the number of strata is larger than the overall sample size. The proposed sampling strategy is based on the use of balanced sampling selection technique and on a GREG-type estimation. The main advantages of the solution is the computational feasibility which allows one to easily implement an overall small area strategy considering jointly the sampling design and the estimator and improving the efficiency of the direct domain estimators. An empirical simulation on real population data and different domain estimators shows the empirical properties of the examined sample strategy.

Description:

Data for Canada, provinces, territories, census metropolitan areas and census agglomerations are shown in this table.

This table is part of the topic 'Education,' which presents data on certificates, diplomas or degrees completed. Data is also available for the major field of study of the highest certificate, diploma or degree completed and the province or country where it was completed. These data can be used to track the distribution of highest levels of educational attainment for the Canadian population in general, and for specific groups such as youth, women or immigrants. The data can also be used to measure the link between level of educational attainment, labour force participation and income.

It is possible to subscribe to all the day-of-release bundles. Refer to Catalogue no. 97-569-XCB for more information.

This table is available free on the Internet, Catalogue no. 97-560-XWE2006035.

Description:

Data for Canada, provinces and territories are shown in this table.

This table is part of the topic 'Education,' which presents data on certificates, diplomas or degrees completed. Data is also available for the major field of study of the highest certificate, diploma or degree completed and the province or country where it was completed. These data can be used to track the distribution of highest levels of educational attainment for the Canadian population in general, and for specific groups such as youth, women or immigrants. The data can also be used to measure the link between level of educational attainment, labour force participation and income.

It is possible to subscribe to all the day-of-release bundles. Refer to Catalogue no. 97-569-XCB for more information.

This table is available free on the Internet, Catalogue no. 97-560-XWE2006036.

Description:

Data for census metropolitan areas, tracted census agglomerations and census tracts are shown in this table.

This table is part of the topic 'Education,' which presents data on certificates, diplomas or degrees completed. Data is also available for the major field of study of the highest certificate, diploma or degree completed and the province or country where it was completed. These data can be used to track the distribution of highest levels of educational attainment for the Canadian population in general, and for specific groups such as youth, women or immigrants. The data can also be used to measure the link between level of educational attainment, labour force participation and income.

It is possible to subscribe to all the day-of-release bundles. Refer to Catalogue no. 97-569-XCB for more information.

Description:

Data for Canada, provinces and territories are shown in this table.

This table is part of the topic 'Education,' which presents data on certificates, diplomas or degrees completed. Data is also available for the major field of study of the highest certificate, diploma or degree completed and the province or country where it was completed. These data can be used to track the distribution of highest levels of educational attainment for the Canadian population in general, and for specific groups such as youth, women or immigrants. The data can also be used to measure the link between level of educational attainment, labour force participation and income.

It is possible to subscribe to all the day-of-release bundles. Refer to Catalogue no. 97-569-XCB for more information.

This table is available free on the Internet, Catalogue no. 97-560-XWE2006038.

Description:

The tables in the topic 'Education' present data on certificates, diplomas or degrees completed. Data is also available for the major field of study of the highest certificate, diploma or degree completed and the province or country where it was completed. These data can be used to track the distribution of highest levels of educational attainment for the Canadian population in general, and for specific groups such as youth, women or immigrants. The data can also be used to measure the link between level of educational attainment, labour force participation and income.

Description:

The review presents detailed and recent statistics of the mining industry, including the production and the value of minerals by kind and by province. It also presents historical tables of values by main groups, the average prices of leading minerals and principal statistics by main group and by province, and diamond drilling of deposits other than fuels. It includes explanatory notes and a bibliography.

Description:

Cycle 21 of the 2007 General Social Survey (GSS) was on "Family, Social Support and Retirement". Data were collected over a 9 month period from March to December 2007 with a sample of approximately 25,000 respondents representing the non-institutionalized population in the 10 provinces. These tables contain data on the prevalence of care given and received by seniors because of long-term health problems, selected employment consequences of providing care to seniors and self-rated stress experienced by caregivers. All tables are available by sex and age groups, and for Canada and the provinces or regions.

Description:

This product brings together statistics on live births, induced abortions and fetal loss (stillbirths and miscarriages) to provide comprehensive statistics on outcomes of pregnancy.

Counts and rates for the three outcomes of pregnancy as well as total pregnancies are presented by the province or territory of residence and by the age group of the woman.

Description:

This annual publication presents data on establishments, employment, payroll, materials, supplies and contract services. It also shows the production, shipments and drillings completed. It includes lists of establishments showing employment size ranges, terms and definitions and a bibliography.

Description: The Participation and Activity Limitation Survey (PALS) is Canada's national survey that gathers information about adults and children whose daily activities are limited by a physical, mental, or other health-related condition or problem.

This report presents a series of tables on the; Total income; Old age security pension and guaranteed income supplement; Canada / Quebec pension plan benefits; Child tax benefit; Other government income; Employment income; Investment income; Retirement income.

Description:

The context of the discussion is the increasing incidence of international surveys, of which one is the International Tobacco Control (ITC) Policy Evaluation Project, which began in 2002. The ITC country surveys are longitudinal, and their aim is to evaluate the effects of policy measures being introduced in various countries under the WHO Framework Convention on Tobacco Control. The challenges of organization, data collection and analysis in international surveys are reviewed and illustrated. Analysis is an increasingly important part of the motivation for large scale cross-cultural surveys. The fundamental challenge for analysis is to discern the real response (or lack of response) to policy change, separating it from the effects of data collection mode, differential non-response, external events, time-in-sample, culture, and language. Two problems relevant to statistical analysis are discussed. The first problem is the question of when and how to analyze pooled data from several countries, in order to strengthen conclusions which might be generally valid. While in some cases this seems to be straightforward, there are differing opinions on the extent to which pooling is possible and reasonable. It is suggested that for formal comparisons, random effects models are of conceptual use. The second problem is to find models of measurement across cultures and data collection modes which will enable calibration of continuous, binary and ordinal responses, and produce comparisons from which extraneous effects have been removed. It is noted that hierarchical models provide a natural way of relaxing requirements of model invariance across groups.

Description:

Dependent interviewing (DI) is used in many longitudinal surveys to "feed forward" data from one wave to the next. Though it is a promising technique which has been demonstrated to enhance data quality in certain respects, relatively little is known about how it is actually administered in the field. This research seeks to address this issue through behavior coding. Various styles of DI were employed in the English Longitudinal Study of Ageing (ELSA) in January, 2006, and recordings were made of pilot field interviews. These recordings were analysed to determine whether the questions (particularly the DI aspects) were administered appropriately and to explore the respondent's reaction to the fed-forward data. Of particular interest was whether respondents confirmed or challenged the previously-reported information, whether the prior wave data came into play when respondents were providing their current-wave answers, and how any discrepancies were negotiated by the interviewer and respondent. Also of interest was to examine the effectiveness of various styles of DI. For example, in some cases the prior wave data was brought forward and respondents were asked to explicitly confirm it; in other cases the previous data was read and respondents were asked if the situation was still the same. Results indicate varying levels of compliance in terms of initial question-reading, and suggest that some styles of DI may be more effective than others.

Description:

In longitudinal surveys nonresponse often occurs in a pattern that is not monotone. We consider estimation of time-dependent means under the assumption that the nonresponse mechanism is last-value-dependent. Since the last value itself may be missing when nonresponse is nonmonotone, the nonresponse mechanism under consideration is nonignorable. We propose an imputation method by first deriving some regression imputation models according to the nonresponse mechanism and then applying nonparametric regression imputation. We assume that the longitudinal data follow a Markov chain with finite second-order moments. No other assumption is imposed on the joint distribution of longitudinal data and their nonresponse indicators. A bootstrap method is applied for variance estimation. Some simulation results and an example concerning the Current Employment Survey are presented.

Description:

Sample weights can be calibrated to reflect the known population totals of a set of auxiliary variables. Predictors of finite population totals calculated using these weights have low bias if these variables are related to the variable of interest, but can have high variance if too many auxiliary variables are used. This article develops an "adaptive calibration" approach, where the auxiliary variables to be used in weighting are selected using sample data. Adaptively calibrated estimators are shown to have lower mean squared error and better coverage properties than non-adaptive estimators in many cases.

Description:

We propose a method for estimating the variance of estimators of changes over time, a method that takes account of all the components of these estimators: the sampling design, treatment of non-response, treatment of large companies, correlation of non-response from one wave to another, the effect of using a panel, robustification, and calibration using a ratio estimator. This method, which serves to determine the confidence intervals of changes over time, is then applied to the Swiss survey of value added.

Description:

The analysis of stratified multistage sample data requires the use of design information such as stratum and primary sampling unit (PSU) identifiers, or associated replicate weights, in variance estimation. In some public release data files, such design information is masked as an effort to avoid their disclosure risk and yet to allow the user to obtain valid variance estimation. For example, in area surveys with a limited number of PSUs, the original PSUs are split or/and recombined to construct pseudo-PSUs with swapped second or subsequent stage sampling units. Such PSU masking methods, however, obviously distort the clustering structure of the sample design, yielding biased variance estimates possibly with certain systematic patterns between two variance estimates from the unmasked and masked PSU identifiers. Some of the previous work observed patterns in the ratio of the masked and unmasked variance estimates when plotted against the unmasked design effect. This paper investigates the effect of PSU masking on variance estimates under cluster sampling regarding various aspects including the clustering structure and the degree of masking. Also, we seek a PSU masking strategy through swapping of subsequent stage sampling units that helps reduce the resulting biases of the variance estimates. For illustration, we used data from the National Health Interview Survey (NHIS) with some artificial modification. The proposed strategy performs very well in reducing the biases of variance estimates. Both theory and empirical results indicate that the effect of PSU masking on variance estimates is modest with minimal swapping of subsequent stage sampling units. The proposed masking strategy has been applied to the 2003-2004 National Health and Nutrition Examination Survey (NHANES) data release.

Description:

The design of a stratified simple random sample without replacement from a finite population deals with two main issues: the definition of a rule to partition the population into strata, and the allocation of sampling units in the selected strata. This article examines a tree-based strategy which plans to approach jointly these issues when the survey is multipurpose and multivariate information, quantitative or qualitative, is available. Strata are formed through a hierarchical divisive algorithm that selects finer and finer partitions by minimizing, at each step, the sample allocation required to achieve the precision levels set for each surveyed variable. In this way, large numbers of constraints can be satisfied without drastically increasing the sample size, and also without discarding variables selected for stratification or diminishing the number of their class intervals. Furthermore, the algorithm tends not to define empty or almost empty strata, thus avoiding the need for strata collapsing aggregations. The procedure was applied to redesign the Italian Farm Structure Survey. The results indicate that the gain in efficiency held using our strategy is nontrivial. For a given sample size, this procedure achieves the required precision by exploiting a number of strata which is usually a very small fraction of the number of strata available when combining all possible classes from any of the covariates.

Description:

Optimum stratification is the method of choosing the best boundaries that make strata internally homogeneous, given some sample allocation. In order to make the strata internally homogenous, the strata should be constructed in such a way that the strata variances for the characteristic under study be as small as possible. This could be achieved effectively by having the distribution of the main study variable known and create strata by cutting the range of the distribution at suitable points. If the frequency distribution of the study variable is unknown, it may be approximated from the past experience or some prior knowledge obtained at a recent study. In this paper the problem of finding Optimum Strata Boundaries (OSB) is considered as the problem of determining Optimum Strata Widths (OSW). The problem is formulated as a Mathematical Programming Problem (MPP), which minimizes the variance of the estimated population parameter under Neyman allocation subject to the restriction that sum of the widths of all the strata is equal to the total range of the distribution. The distributions of the study variable are considered as continuous with Triangular and Standard Normal density functions. The formulated MPPs, which turn out to be multistage decision problems, can then be solved using dynamic programming technique proposed by Bühler and Deutler (1975). Numerical examples are presented to illustrate the computational details. The results obtained are also compared with the method of Dalenius and Hodges (1959) with an example of normal distribution.

Description:

This paper considers the optimum allocation in multivariate stratified sampling as a nonlinear matrix optimisation of integers. As a particular case, a nonlinear problem of the multi-objective optimisation of integers is studied. A full detailed example including some of proposed techniques is provided at the end of the work.

Description:

The present work illustrates a sampling strategy useful for obtaining planned sample size for domains belonging to different partitions of the population and in order to guarantee the sampling errors of domain estimates be lower than given thresholds. The sampling strategy that covers the multivariate multi-domain case is useful when the overall sample size is bounded and consequently the standard solution of using a stratified sample with the strata given by cross-classification of variables defining the different partitions is not feasible since the number of strata is larger than the overall sample size. The proposed sampling strategy is based on the use of balanced sampling selection technique and on a GREG-type estimation. The main advantages of the solution is the computational feasibility which allows one to easily implement an overall small area strategy considering jointly the sampling design and the estimator and improving the efficiency of the direct domain estimators. An empirical simulation on real population data and different domain estimators shows the empirical properties of the examined sample strategy.

Description:

This paper focuses on the role of investments in infrastructure in Canada. The size of infrastructure investments relative to other capital stock sets this country apart from most other Organisation for Economic Co-operation and Development countries. The paper reviews the approaches taken by other researchers to define infrastructure. It then outlines a taxonomy to define those assets that should be considered as infrastructure and that can be used to assess the importance of different types of capital investments. It briefly considers how to define the portion of infrastructure that should be considered 'public'. The final two parts of the paper apply the proposed classification system to data on Canada's capital stock, and ask the following questions: how much infrastructure does Canada have and in which sectors of the economy is this infrastructure located? Finally, the paper investigates how Canada's infrastructure has evolved over the last four decades, both in the commercial and non-commercial sectors, and compares these trends with the pattern that can be found in the United States.

Description:

This guide focuses on the following demographic variables: Mobility and migration.

Provides information that enables users to effectively use, apply and interpret data from the 2006 Census. Each guide contains definitions and explanations on census concepts, data quality and historical comparability. Additional information will be included for specific variables to help general users better understand the concepts and questions used in the census.

Description:

These guides provide information that enables users to effectively use, apply and interpret data from the 2006 Census. Each guide contains definitions and explanations on census concepts, data quality and historical comparability. Additional information will be included for specific variables to help general users better understand the concepts and questions used in the census.

Description:

Starting in 1994, the Survey of Labour and Income Dynamics (SLID) will follow individuals and families for at least six years, tracking their labour market experiences, changes in income and family circumstances. An initial proposal for the content of SLID, entitled "Content of the Survey of Labour and Income Dynamics : Discussion Paper", was distributed in February 1992.

That paper served as a background document for consultation with and a review by interested users. The content underwent significant change during this process. Based upon the revised content, a large-scale test of SLID will be conducted in February and May 1993.

The present document outlines the income and wealth content to be tested in May 1993. This document is really a continuation of SLID Research Paper Series 92-01A, which outlines the demographic and labour content used in the January /February 1993 test.

Description:

When a survey respondent is asked to recall various events, it is known that the quality of the responses diminishes as the length of recall increases. On the other hand, increasing the frequency of data collection increases both the costs of collection and the burden on the respondents. The paper examines options which attempt to strike a reasonable balance between these factors. As it relates to this decision, the paper also describes how the sample has been designed to ensure that it remains representative of the target population, both for a given year and over time.

The conclusion is that, at this time, SLID should collect labour data in January to cover the previous calendar year and to collect income data in May, again to cover the previous calendar year.

Description:

A Preliminary Interview will be conducted on the first panel of SLID, in January 1993, as a supplement to the Labour Force Survey. The first panel is made up of about 20,000 households that are rotating out of the Labour Force Survey in January and February, 1993.

The purpose of this document is to provide a description of the purpose of the SLID Preliminary Interview and the question wordings to be used.

Description:

This guide presents information of interest to users of data from the Survey of Household Spending, which gathers information on the spending habits, dwelling characteristics and household equipment of Canadian households. The survey covers private households in the 10 provinces. (The territories are surveyed every second year, starting in 1999.)

This guide includes definitions of survey terms and variables, as well as descriptions of survey methodology and data quality. One section describes the various statistics that can be created using expenditure data (e.g., budget share, market share, aggregates and medians).

Description:

This paper provides an overview of the productivity program at Statistics Canada and a brief description of Canada's productivity performance. The paper defines productivity and the various measures that are used to investigate different aspects of productivity growth. It describes the difference between partial productivity measures (such as labour productivity) and a more complete measure (multifactor productivity) and the advantages and disadvantages of each. The paper explains why productivity is important. It outlines how productivity growth fits into the growth accounting framework and how this framework is used to examine the various sources of economic growth. The paper briefly discusses the challenges that face statisticians in measuring productivity growth. It also provides an overview of Canada's long-term productivity performance and compares Canada to the United States - both in terms of productivity levels and productivity growth rates.

Description:

The Record Linkage Overview describes the process used in annual internal record linkage of the Canadian Cancer Registry. The steps include: preparation; pre-processing; record linkage; post-processing; analysis and resolution; resolution entry; and, resolution processing.

Description:

The compendium of Canadian Cancer Registry procedures manuals set out the rules for reporting cancer data to the CCR for all provincial and territorial cancer registries.