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Hidden human populations, the Internet, and other networked structures conceptualized mathematically as graphs are inherently hard to sample by conventional means, and the most effective study designs usually involve procedures that select the sample by adaptively following links from one node to another. Sample data obtained in such studies are generally not representative at face value of the larger population of interest. However, a number of design and model based methods are now available for effective inference from such samples. The design based methods have the advantage that they do not depend on an assumed population model, but do depend for their validity on the design being implemented in a controlled and known way, which can be difficult or impossible in practice. The model based methods allow greater flexibly in the design, but depend on modeling of the population using stochastic graph models and also depend on the design being ignorable or of known form so that it can be included in the likelihood or Bayes equations. For both the design and the model based methods, the weak point often is the lack of control in how the initial sample is obtained, from which link-tracing commences. The designs described in this paper offer a third way, in which the sample selection probabilities become step by step less dependent on the initial sample selection. A Markov chain "random walk" model idealizes the natural design tendencies of a link-tracing selection sequence through a graph. This paper introduces uniform and targeted walk designs in which the random walk is nudged at each step to produce a design with the desired stationary probabilities. A sample is thus obtained that in important respects is representative at face value of the larger population of interest, or that requires only simple weighting factors to make it so.

This publication presents a series of tabulations produced from the General Social Survey on time use of Canadians. It includes information on average amounts of time spent on various activities by sex, by age, by selected role groups.

This document summarizes the results of content analyses of the 2004 Census Test. The first section briefly explains the context of the content analyses by describing the nature of the sample, its limitations and the strategies used to evaluate data quality. The second section provides an overview of the results for questions that have not changed since the 2001 Census by describing the similarities between 2001 and 2004 distributions and non-response rates. The third section evaluates data quality of new census questions or questions that have changed substantially: same-sex married couples, ethnic origins, levels of schooling, location where highest diploma was obtained, school attendance, permission to access income tax files, and permission to make personal data publicly available 92 years after the census. The last section summarizes the overall results for questions whose content was coded and evaluated as part of the 2004 test, namely industry, occupation and place of work variables.

This article presents an analysis of Census at School survey results that shows what students themselves had to say about their reading and associated daily habits. It was written by Statistics Canada analysts as an example to students of the type of detailed analysis that can be made using Canadian Census at School results. The article uses data that were collected from over 22,000 students across Canada during the 2004-2005 academic year. Census at School is an international classroom project that teaches students aged 8 to 18 about statistical enquiry and census-taking. Students anonymously fill in an online questionnaire about themselves - their height, time use, eating habits and much more - and then use their class results to learn statistical concepts, practice data analysis and explore social issues. Their responses also become part of national and international project databases that are used for teaching statistics.

The Census at School statistical literacy project is not an official Statistics Canada survey conducted under the Statistics Act. Schools; students participate on a voluntary basis and the data collected are not representative of Canada's student population. This is clearly stated with the summary Canadian results that are made available on the project website for the benefit of participating students.

Hot deck imputation is a procedure in which missing items are replaced with values from respondents. A model supporting such procedures is the model in which response probabilities are assumed equal within imputation cells. An efficient version of hot deck imputation is described for the cell response model and a computationally efficient variance estimator is given. An approximation to the fully efficient procedure in which a small number of values are imputed for each nonrespondent is described. Variance estimation procedures are illustrated in a Monte Carlo study.

The Ethnic Diversity Survey generated methodological challenges like choosing the sampling plan, developing the questionnaire, collecting the data, weighting the data and estimating the variance.

For a study on smoking cessation programs, respondents were found via referrals from key informants. A challenge was tracking the calling process and keeping records of information obtained during telephone calls.

The paradigm shift in disability limits participation of persons with disabilities in the survey process. Evidence of barriers to survey participation is reviewed and approaches to reducing barriers are discussed.

I will try to look at the future of survey research in the light of the incredible developments in information technology. I will speculate on what new technologies might contribute to doing surveys differently.

The testing of questionnaires with specialized populations such as Aboriginal people, homosexuals, bisexuals, children, victims of abuse brings challenges: identifying respondents, testing methodology, location of testing, respondent rapport and trust.

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 help with everyday activities as well as unmet needs and help providers.

This publication presents a series of tabulations produced from the General Social Survey on time use of Canadians. It includes information on average amounts of time spent on various activities by sex, by age, by selected role groups.

This report presents the results of a pilot survey conducted by Statistics Canada to measure the fuel consumption of on-road motor vehicles registered in Canada. This study was carried out in connection with the Canadian Vehicle Survey (CVS) which collects information on road activity such as distance traveled, number of passengers and trip purpose.

Cycle 15 of the General Social Survey (GSS) is the third cycle to collect detailed information on family life in Canada. The previous GSS cycles that collected family data were Cycles 5 and 10. Topics include demographic characteristics such as age, sex, and marital status; family origin of parents; brothers and sisters; marriages of respondent; common-law unions of respondent; fertility and family intentions; values and attitudes; education history; work history; main activity and other characteristics.

The target population for Cycle 15 of the GSS is all persons 15 years of age and older in Canada, excluding residents of the Yukon, Northwest Territories, and Nunavut, and full-time residents of institutions.

This table is part of the topic "Ethnocultural Portrait of Canada," which shows 2001 Census data on ethnic groups in Canada, such as their size, geographic location and demographic characteristics. Similar information is available for Canada's visible minority population.

Data on the socio-economic characteristics of these populations will be available at a later date. As well, data on religions in Canada will be available in May 2003.

Additional information on ethnocultural diversity will be available from the Ethnic Diversity Survey in the summer of 2003.

This table can be found in the Topic Bundle: Ethnocultural Portrait of Canada, 2001 Census, Catalogue No. 97F0010XCB2001000.

It is also possible to subscribe to all the day-of-release bundles. For more information, refer to Catalogue No. 97F0023XCB.

This table is available FREE on the Internet, Catalogue No. 97F0010XIE2001001.

The National Longitudinal Survey of Children and Youth (NLSCY), developed jointly by Human Resources Development Canada and Statistics Canada, is a comprehensive survey which follows the development of children in Canada and paints a picture of their lives. The survey monitors children's development and measures the incidence of various factors that influence their development, both positively and negatively.

Cycle 13 of the General Social Survey (GSS) is the third cycle (following cycles 3 and 8) that collected information in 1999 on the nature and extent of criminal victimisation in Canada. Focus content for cycle 13 addressed two areas of emerging interest: public perception toward alternatives to imprisonment; and spousal violence and senior abuse. Other subjects common to all three cycles include perceptions of crime, police and courts; crime prevention precautions; accident and crime screening sections; and accident and crime incident reports. The target population of the GSS is all individuals aged 15 and over living in a private household in one of the ten provinces.

The National Population Health Survey (NPHS) program is designed to collect information related to the health of the Canadian population. The first cycle of data collection began in 1994. The institutional component includes long-term residents (expected to stay longer than six months) in health care facilities with four or more beds in Canada with the principal exclusion of the Yukon and the Northwest Teritories. The document has been produced to facilitate the manipulation of the 1996-1997 microdata file containing survey results. The main variables include: demography, health status, chronic conditions, restriction of activity, socio-demographic, and others.

Information in this microdata file refers to survey data collected in September - November, 1994 for persons 15 years of age and older in Canada's ten provinces. The survey's main data objectives were to measure the prevalence and patterns of alcohol and other drug use, to assess harm and other consequences of drug use and to evaluate trends in recent patterns of use. Canada's Alcohol and Other Drugs Survey (CADS) also updates and expands upon data collected in the first survey, the National Alcohol and Other Drugs Survey (NADS), conducted in 1989.

Cycle 11 collected data from persons 15 years and older and concentrated on help given or received during temporary difficult times or out of necessity due to long-term health or physical limitations in daily activities either inside or outside the household. The target population of the General Social Survey consisted of all individuals aged 15 and over living in a private household in one of the ten provinces.

Hot deck imputation is a procedure in which missing items are replaced with values from respondents. A model supporting such procedures is the model in which response probabilities are assumed equal within imputation cells. An efficient version of hot deck imputation is described for the cell response model and a computationally efficient variance estimator is given. An approximation to the fully efficient procedure in which a small number of values are imputed for each nonrespondent is described. Variance estimation procedures are illustrated in a Monte Carlo study.

The Ethnic Diversity Survey generated methodological challenges like choosing the sampling plan, developing the questionnaire, collecting the data, weighting the data and estimating the variance.

For a study on smoking cessation programs, respondents were found via referrals from key informants. A challenge was tracking the calling process and keeping records of information obtained during telephone calls.

The paradigm shift in disability limits participation of persons with disabilities in the survey process. Evidence of barriers to survey participation is reviewed and approaches to reducing barriers are discussed.

I will try to look at the future of survey research in the light of the incredible developments in information technology. I will speculate on what new technologies might contribute to doing surveys differently.

The testing of questionnaires with specialized populations such as Aboriginal people, homosexuals, bisexuals, children, victims of abuse brings challenges: identifying respondents, testing methodology, location of testing, respondent rapport and trust.

The item count technique, which is an indirect questioning technique, was devised to estimate the proportion of people for whom a sensitive key item holds true. This is achieved by having respondents report the number of descriptive phrases, from a list of several phrases that they believe apply to themselves. The list for half the sample includes the key item, and the list for the other half does not include the key item. The difference in mean number of selected phrases is an estimator of the proportion. In this article, we propose two new methods, referred to as the cross-based method and the double cross-based method, by which proportions in subgroups or domains are estimated based on the data obtained via the item count technique. In order to assess the precision of the proposed methods, we conducted simulation experiments using data obtained from a survey of the Japanese national character. The results illustrate that the double cross-based method is much more accurate than the traditional stratified method, and is less likely to produce illogical estimates.

We use hierarchical Bayesian models to analyze body mass index (BMI) data of children and adolescents with nonignorable nonresponse from the Third National Health and Nutrition Examination Survey (NHANES III). Our objective is to predict the finite population mean BMI and the proportion of respondents for domains formed by age, race and sex (covariates in the regression models) in each of thirty five large counties, accounting for the nonrespondents. Markov chain Monte Carlo methods are used to fit the models (two selection and two pattern mixture) to the NHANES III BMI data. Using a deviance measure and a cross-validation study, we show that the nonignorable selection model is the best among the four models. We also show that inference about BMI is not too sensitive to the model choice. An improvement is obtained by including a spline regression into the selection model to reflect changes in the relationship between BMI and age.

This document examines the use of a follow-up survey of non-respondents to augment the respondents from the main survey where response rates are low.

Survey statisticians have long known that the question-answer process is a source of response effects that contribute to non-random measurement error. In the past two decades there has been substantial progress toward understanding these sources of error by applying concepts from social and cognitive psychology to the study of the question-answer process. This essay reviews the development of these approaches, discusses the present state of our knowledge, and suggests some research priorities for the future.

The paper examines the results of an initial evaluation of the effectiveness of the lighter, non-bureaucratic approach to questionnaire design called the SLID (Survey of Labour and Income Dynamics ) Notebook

This report presents the results of the May 1993 Survey of Labour and Income Dynamics (SLID) test as they relate to the wealth items, at the individual level and at the family level.

This paper examines the issues and the procedures designed to maintain a representative sample of the population for the Survey of Labour and Income Dynamics (SLID).

This paper describes the Survey of Labour and Income Dynamics (SLID) following rules, which govern who is traced and who is interviewed. It also outlines the conceptual basis for these procedures.

This report presents general observations of the first annual Survey of Labour and Income Dynamics (SLID) income interview by members of the head office project team. It also gives a summary of responses from a subset of interviewers who were asked to complete a debriefing questionnaire after completing SLID collection.

This research paper represents a reference guide for the contact and demographic modules of the Survey of Labour and Income Dynamics (SLID).

This paper presents comments from a sample of interviewers from each regional office who were selected to complete a debriefing questionnaire to evaluate the Survey of Labour and Income Dynamics (SLID) 1995 income interview.