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Results
All (186)
All (186) (20 to 30 of 186 results)
- Articles and reports: 12-001-X201100211605Description:
Composite imputation is often used in business surveys. The term "composite" means that more than a single imputation method is used to impute missing values for a variable of interest. The literature on variance estimation in the presence of composite imputation is rather limited. To deal with this problem, we consider an extension of the methodology developed by Särndal (1992). Our extension is quite general and easy to implement provided that linear imputation methods are used to fill in the missing values. This class of imputation methods contains linear regression imputation, donor imputation and auxiliary value imputation, sometimes called cold-deck or substitution imputation. It thus covers the most common methods used by national statistical agencies for the imputation of missing values. Our methodology has been implemented in the System for the Estimation of Variance due to Nonresponse and Imputation (SEVANI) developed at Statistics Canada. Its performance is evaluated in a simulation study.
Release date: 2011-12-21 - 22. Maximum likelihood estimation for contingency tables and logistic regression with incorrectly linked data ArchivedArticles and reports: 12-001-X201100111444Description:
Data linkage is the act of bringing together records that are believed to belong to the same unit (e.g., person or business) from two or more files. It is a very common way to enhance dimensions such as time and breadth or depth of detail. Data linkage is often not an error-free process and can lead to linking a pair of records that do not belong to the same unit. There is an explosion of record linkage applications, yet there has been little work on assuring the quality of analyses using such linked files. Naively treating such a linked file as if it were linked without errors will, in general, lead to biased estimates. This paper develops a maximum likelihood estimator for contingency tables and logistic regression with incorrectly linked records. The estimation technique is simple and is implemented using the well-known EM algorithm. A well known method of linking records in the present context is probabilistic data linking. The paper demonstrates the effectiveness of the proposed estimators in an empirical study which uses probabilistic data linkage.
Release date: 2011-06-29 - Articles and reports: 12-001-X201100111448Description:
In two-phase sampling for stratification, the second-phase sample is selected by a stratified sample based on the information observed in the first-phase sample. We develop a replication-based bias adjusted variance estimator that extends the method of Kim, Navarro and Fuller (2006). The proposed method is also applicable when the first-phase sampling rate is not negligible and when second-phase sample selection is unequal probability Poisson sampling within each stratum. The proposed method can be extended to variance estimation for two-phase regression estimators. Results from a limited simulation study are presented.
Release date: 2011-06-29 - 24. Comparison of survey regression techniques in the context of small area estimation of poverty ArchivedArticles and reports: 12-001-X201000211378Description:
One key to poverty alleviation or eradication in the third world is reliable information on the poor and their location, so that interventions and assistance can be effectively targeted to the neediest people. Small area estimation is one statistical technique that is used to monitor poverty and to decide on aid allocation in pursuit of the Millennium Development Goals. Elbers, Lanjouw and Lanjouw (ELL) (2003) proposed a small area estimation methodology for income-based or expenditure-based poverty measures, which is implemented by the World Bank in its poverty mapping projects via the involvement of the central statistical agencies in many third world countries, including Cambodia, Lao PDR, the Philippines, Thailand and Vietnam, and is incorporated into the World Bank software program PovMap. In this paper, the ELL methodology which consists of first modeling survey data and then applying that model to census information is presented and discussed with strong emphasis on the first phase, i.e., the fitting of regression models and on the estimated standard errors at the second phase. Other regression model fitting procedures such as the General Survey Regression (GSR) (as described in Lohr (1999) Chapter 11) and those used in existing small area estimation techniques: Pseudo-Empirical Best Linear Unbiased Prediction (Pseudo-EBLUP) approach (You and Rao 2002) and Iterative Weighted Estimating Equation (IWEE) method (You, Rao and Kovacevic 2003) are presented and compared with the ELL modeling strategy. The most significant difference between the ELL method and the other techniques is in the theoretical underpinning of the ELL model fitting procedure. An example based on the Philippines Family Income and Expenditure Survey is presented to show the differences in both the parameter estimates and their corresponding standard errors, and in the variance components generated from the different methods and the discussion is extended to the effect of these on the estimated accuracy of the final small area estimates themselves. The need for sound estimation of variance components, as well as regression estimates and estimates of their standard errors for small area estimation of poverty is emphasized.
Release date: 2010-12-21 - 25. Linearization variance estimation for generalized raking estimators in the presence of nonresponse ArchivedArticles and reports: 12-001-X201000211380Description:
Alternative forms of linearization variance estimators for generalized raking estimators are defined via different choices of the weights applied (a) to residuals and (b) to the estimated regression coefficients used in calculating the residuals. Some theory is presented for three forms of generalized raking estimator, the classical raking ratio estimator, the 'maximum likelihood' raking estimator and the generalized regression estimator, and for associated linearization variance estimators. A simulation study is undertaken, based upon a labour force survey and an income and expenditure survey. Properties of the estimators are assessed with respect to both sampling and nonresponse. The study displays little difference between the properties of the alternative raking estimators for a given sampling scheme and nonresponse model. Amongst the variance estimators, the approach which weights residuals by the design weight can be severely biased in the presence of nonresponse. The approach which weights residuals by the calibrated weight tends to display much less bias. Varying the choice of the weights used to construct the regression coefficients has little impact.
Release date: 2010-12-21 - Articles and reports: 12-001-X201000211381Description:
Taylor linearization methods are often used to obtain variance estimators for calibration estimators of totals and nonlinear finite population (or census) parameters, such as ratios, regression and correlation coefficients, which can be expressed as smooth functions of totals. Taylor linearization is generally applicable to any sampling design, but it can lead to multiple variance estimators that are asymptotically design unbiased under repeated sampling. The choice among the variance estimators requires other considerations such as (i) approximate unbiasedness for the model variance of the estimator under an assumed model, and (ii) validity under a conditional repeated sampling framework. Demnati and Rao (2004) proposed a unified approach to deriving Taylor linearization variance estimators that leads directly to a unique variance estimator that satisfies the above considerations for general designs. When analyzing survey data, finite populations are often assumed to be generated from super-population models, and analytical inferences on model parameters are of interest. If the sampling fractions are small, then the sampling variance captures almost the entire variation generated by the design and model random processes. However, when the sampling fractions are not negligible, the model variance should be taken into account in order to construct valid inferences on model parameters under the combined process of generating the finite population from the assumed super-population model and the selection of the sample according to the specified sampling design. In this paper, we obtain an estimator of the total variance, using the Demnati-Rao approach, when the characteristics of interest are assumed to be random variables generated from a super-population model. We illustrate the method using ratio estimators and estimators defined as solutions to calibration weighted estimating equations. Simulation results on the performance of the proposed variance estimator for model parameters are also presented.
Release date: 2010-12-21 - Articles and reports: 12-001-X201000111247Description:
In this paper, the problem of estimating the variance of various estimators of the population mean in two-phase sampling has been considered by jackknifing the two-phase calibrated weights of Hidiroglou and Särndal (1995, 1998). Several estimators of population mean available in the literature are shown to be the special cases of the technique developed here, including those suggested by Rao and Sitter (1995) and Sitter (1997). By following Raj (1965) and Srivenkataramana and Tracy (1989), some new estimators of the population mean are introduced and their variances are estimated through the proposed jackknife procedure. The variance of the chain ratio and regression type estimators due to Chand (1975) are also estimated using the jackknife. A simulation study is conducted to assess the efficiency of the proposed jackknife estimators relative to the usual estimators of variance.
Release date: 2010-06-29 - 28. Bayesian penalized spline model-based inference for finite population proportion in unequal probability sampling ArchivedArticles and reports: 12-001-X201000111250Description:
We propose a Bayesian Penalized Spline Predictive (BPSP) estimator for a finite population proportion in an unequal probability sampling setting. This new method allows the probabilities of inclusion to be directly incorporated into the estimation of a population proportion, using a probit regression of the binary outcome on the penalized spline of the inclusion probabilities. The posterior predictive distribution of the population proportion is obtained using Gibbs sampling. The advantages of the BPSP estimator over the Hájek (HK), Generalized Regression (GR), and parametric model-based prediction estimators are demonstrated by simulation studies and a real example in tax auditing. Simulation studies show that the BPSP estimator is more efficient, and its 95% credible interval provides better confidence coverage with shorter average width than the HK and GR estimators, especially when the population proportion is close to zero or one or when the sample is small. Compared to linear model-based predictive estimators, the BPSP estimators are robust to model misspecification and influential observations in the sample.
Release date: 2010-06-29 - Articles and reports: 82-622-X2010004Geography: CanadaDescription:
Aboriginal people - First Nations, Métis and Inuit - comprise a growing proportion of the Canadian population. Despite the younger average age of these populations, First Nations, Métis and Inuit people tend to suffer a greater burden of morbidity and mortality than non-Aboriginal Canadians. This may be due, in part, to higher rates of socio-economic disadvantage in Aboriginal populations.
Release date: 2010-06-23 - 30. Evaluating the hyperactivity/inattention subscale of the National Longitudinal Survey of Children and Youth ArchivedArticles and reports: 82-003-X201000211234Geography: CanadaDescription:
This article evaluates the parent-reported Hyperactivity/Inattention Subscale of the National Longitudinal Survey of Children and Youth with data from cycle 1 (1994/1995) of the survey.
Release date: 2010-06-16
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Data (2)
Data (2) ((2 results))
- Public use microdata: 99M0001XDescription: The Individuals File, 2011 National Household Survey (Public Use Microdata Files) provides data on the characteristics of the Canadian population. The file contains a 2.7% sample of anonymous responses to the 2011 National Household Survey (NHS) questionnaire. The files have been carefully scrutinized to ensure the complete confidentiality of the individual responses and geographic identifiers have been restricted to provinces/territories and metropolitan areas. With 133 variables, this comprehensive tool is excellent for policy analysts, pollsters, social researchers and anyone interested in modelling and performing statistical regression analysis using National Household Survey data.
Microdata files uniquely provide users access to non-aggregated data. The PUMFs user can group and manipulate these variables to suit data and research requirements. Tabulations excluded from other NHS products can be created or relationships between variables can be analyzed using different statistical tests. PUMFs provide quick access to a comprehensive social and economic database about Canada and its people.
This product, offered on DVD-ROM, contains the data file (in ASCII format); user documentation and supporting information; all licence agreements; and SAS, SPSS and Stata program source codes to enable users to read the set of records. It is important to note that users will require knowledge of data manipulation packages (or software) such as SAS, SPSS or Stata to use this product.
Release date: 2023-09-12 - 2. Bilingualism and earnings ArchivedTable: 75-001-X19890022277Description:
This study compares the earnings of bilingual and unilingual workers in three urban centres: Montreal, Toronto and Ottawa-Hull. Differences in the earnings of bilingual and unilingual workers are considered in the light of several demographic and job-related traits.
Release date: 1989-06-30
Analysis (174)
Analysis (174) (40 to 50 of 174 results)
- 41. Survey weighted hat matrix and leverages ArchivedArticles and reports: 12-001-X200900110881Description:
Regression diagnostics are geared toward identifying individual points or groups of points that have an important influence on a fitted model. When fitting a model with survey data, the sources of influence are the response variable Y, the predictor variables X, and the survey weights, W. This article discusses the use of the hat matrix and leverages to identify points that may be influential in fitting linear models due to large weights or values of predictors. We also contrast findings that an analyst will obtain if ordinary least squares is used rather than survey weighted least squares to determine which points are influential.
Release date: 2009-06-22 - Articles and reports: 12-001-X200900110882Description:
The bootstrap technique is becoming more and more popular in sample surveys conducted by national statistical agencies. In most of its implementations, several sets of bootstrap weights accompany the survey microdata file given to analysts. So far, the use of the technique in practice seems to have been mostly limited to variance estimation problems. In this paper, we propose a bootstrap methodology for testing hypotheses about a vector of unknown model parameters when the sample has been drawn from a finite population. The probability sampling design used to select the sample may be informative or not. Our method uses model-based test statistics that incorporate the survey weights. Such statistics are usually easily obtained using classical software packages. We approximate the distribution under the null hypothesis of these weighted model-based statistics by using bootstrap weights. An advantage of our bootstrap method over existing methods of hypothesis testing with survey data is that, once sets of bootstrap weights are provided to analysts, it is very easy to apply even when no specialized software dealing with complex surveys is available. Also, our simulation results suggest that, overall, it performs similarly to the Rao-Scott procedure and better than the Wald and Bonferroni procedures when testing hypotheses about a vector of linear regression model parameters.
Release date: 2009-06-22 - 43. In this issue (Vol. 35, no. 1) ArchivedArticles and reports: 12-001-X200900110892Description:
In this Issue is a column where the Editor biefly presents each paper of the current issue of Survey Methodology. As well, it sometimes contain informations on structure or management changes in the journal.
Release date: 2009-06-22 - 44. International Adult Literacy Survey [Series] ArchivedJournals and periodicals: 89-552-MGeography: CanadaDescription:
The International Adult Literacy Survey (IALS) was a seven-country initiative conducted in the fall of 1994. Its goal was to create comparable literacy profiles across national, linguistic and cultural boundaries. Successive waves of the survey now encompass close to 30 countries around the world. This monograph series features detailed studies from the IALS database by literacy scholars and experts in Canada and the United States. The research is primarily funded by Human Resources Development Canada. Monographs focus on current policy issues and cover topics such as adult training, literacy skill match and mismatch in the workplace, seniors' literacy skills and health, literacy and economic security, and many others.
Release date: 2008-07-21 - Articles and reports: 82-622-X2008002Geography: CanadaDescription: This study uses data from the Canadian Survey of Experiences with Primary Health Care to assess the degree to which Canadians have access to primary health care teams and the impact of those teams on processes of care and on outcomes. The study is comprised of three projects: determinants of access to primary health care teams (Project 1); the impact of primary health care teams on various processes of care (Project 2); and identification of pathways through which primary health care teams affect outcomes of care (Project 3).Release date: 2008-07-15
- 46. Generalized regression estimators of a finite population total using the Box-Cox technique ArchivedArticles and reports: 12-001-X200800110610Description:
A new generalized regression estimator of a finite population total based on the Box-Cox transformation technique and its variance estimator are proposed under a general unequal probability sampling design. By being design consistent, the proposed estimator maintains the robustness property of the GREG estimator even if the underlying model fails. Furthermore, the Box-Cox technique automatically finds a reasonable transformation for the dependent variable using the data. The robustness and efficiency of the new estimator are evaluated analytically and via Monte Carlo simulation studies.
Release date: 2008-06-26 - Articles and reports: 12-001-X200800110615Description:
We consider optimal sampling rates in element-sampling designs when the anticipated analysis is survey-weighted linear regression and the estimands of interest are linear combinations of regression coefficients from one or more models. Methods are first developed assuming that exact design information is available in the sampling frame and then generalized to situations in which some design variables are available only as aggregates for groups of potential subjects, or from inaccurate or old data. We also consider design for estimation of combinations of coefficients from more than one model. A further generalization allows for flexible combinations of coefficients chosen to improve estimation of one effect while controlling for another. Potential applications include estimation of means for several sets of overlapping domains, or improving estimates for subpopulations such as minority races by disproportionate sampling of geographic areas. In the motivating problem of designing a survey on care received by cancer patients (the CanCORS study), potential design information included block-level census data on race/ethnicity and poverty as well as individual-level data. In one study site, an unequal-probability sampling design using the subjectss residential addresses and census data would have reduced the variance of the estimator of an income effect by 25%, or by 38% if the subjects' races were also known. With flexible weighting of the income contrasts by race, the variance of the estimator would be reduced by 26% using residential addresses alone and by 52% using addresses and races. Our methods would be useful in studies in which geographic oversampling by race-ethnicity or socioeconomic characteristics is considered, or in any study in which characteristics available in sampling frames are measured with error.
Release date: 2008-06-26 - 48. In this issue (Vol. 34, no. 1) ArchivedArticles and reports: 12-001-X200800110642Description:
In this Issue is a column where the Editor biefly presents each paper of the current issue of Survey Methodology. As well, it sometimes contain informations on structure or management changes in the journal.
Release date: 2008-06-26 - 49. Robust Bayesian predictive inference for the finite population quantile of a small area ArchivedArticles and reports: 11-522-X200600110392Description:
We use a robust Bayesian method to analyze data with possibly nonignorable nonresponse and selection bias. A robust logistic regression model is used to relate the response indicators (Bernoulli random variable) to the covariates, which are available for everyone in the finite population. This relationship can adequately explain the difference between respondents and nonrespondents for the sample. This robust model is obtained by expanding the standard logistic regression model to a mixture of Student's distributions, thereby providing propensity scores (selection probability) which are used to construct adjustment cells. The nonrespondents' values are filled in by drawing a random sample from a kernel density estimator, formed from the respondents' values within the adjustment cells. Prediction uses a linear spline rank-based regression of the response variable on the covariates by areas, sampling the errors from another kernel density estimator; thereby further robustifying our method. We use Markov chain Monte Carlo (MCMC) methods to fit our model. The posterior distribution of a quantile of the response variable is obtained within each sub-area using the order statistic over all the individuals (sampled and nonsampled). We compare our robust method with recent parametric methods
Release date: 2008-03-17 - Articles and reports: 11-522-X200600110416Description:
Application of standard methods to survey data without accounting for the design features and weight adjustments can lead to erroneous inferences. Bootstrap methods offer an attractive option to the analyst for taking account of the design features and weight adjustments. The data file consists of the full-sample final weights and associated bootstrap final weights for a large number of bootstrap replicates as well as the observed data on the sample elements. We show how such data files can be used to analyze survey data in a straightforward manner using weighted estimating equations. A one-step estimating function bootstrap method that avoids some difficulties with the bootstrap is also discussed.
Release date: 2008-03-17
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Reference (10)
Reference (10) ((10 results))
- Surveys and statistical programs – Documentation: 11-522-X20010016308Description:
This paper discusses in detail issues dealing with the technical aspects of designing and conducting surveys. It is intended for an audience of survey methodologists.
The Census Bureau uses response error analysis to evaluate the effectiveness of survey questions. For a given survey, questions that are deemed critical to the survey or considered problematic from past examination are selected for analysis. New or revised questions are prime candidates for re-interview. Re-interview is a new interview where a subset of questions from the original interview are re-asked to a sample of the survey respondents. For each re-interview question, the proportion of respondents who give inconsistent responses is evaluated. The "Index of Inconsistency" is used as the measure of response variance. Each question is labelled low, moderate, or high in response variance. In high response variance cases, the questions are put through cognitive testing, and modifications to the question are recommended.
The Schools and Staffing Survey (SASS) sponsored by The National Center for Education Statistics (NCES), is also investigated for response error analysis and the possible relationships between inconsistent responses and characteristics of the schools and teachers in that survey. Results of this analysis can be used to change survey procedures and improve data quality.
Release date: 2002-09-12 - 2. Particulate matter and daily mortality: Combining time series information from eight U.S. cities ArchivedSurveys and statistical programs – Documentation: 11-522-X19990015656Description:
Time series studies have shown associations between air pollution concentrations and morbidity and mortality. These studies have largely been conducted within single cities, and with varying methods. Critics of these studies have questioned the validity of the data sets used and the statistical techniques applied to them; the critics have noted inconsistencies in findings among studies and even in independent re-analyses of data from the same city. In this paper we review some of the statistical methods used to analyze a subset of a national data base of air pollution, mortality and weather assembled during the National Morbidity and Mortality Air Pollution Study (NMMAPS).
Release date: 2000-03-02 - 3. A donor imputation system to create a census database fully adjusted for underenumeration ArchivedSurveys and statistical programs – Documentation: 11-522-X19990015668Description:
Following the problems with estimating underenumeration in the 1991 Census of England and Wales the aim for the 2001 Census is to create a database that is fully adjusted to net underenumeration. To achieve this, the paper investigates weighted donor imputation methodology that utilises information from both the census and census coverage survey (CCS). The US Census Bureau has considered a similar approach for their 2000 Census (see Isaki et al 1998). The proposed procedure distinguishes between individuals who are not counted by the census because their household is missed and those who are missed in counted households. Census data is linked to data from the CCS. Multinomial logistic regression is used to estimate the probabilities that households are missed by the census and the probabilities that individuals are missed in counted households. Household and individual coverage weights are constructed from the estimated probabilities and these feed into the donor imputation procedure.
Release date: 2000-03-02 - Surveys and statistical programs – Documentation: 11-522-X19990015682Description:
The application of dual system estimation (DSE) to matched Census / Post Enumeration Survey (PES) data in order to measure net undercount is well understood (Hogan, 1993). However, this approach has so far not been used to measure net undercount in the UK. The 2001 PES in the UK will use this methodology. This paper presents the general approach to design and estimation for this PES (the 2001 Census Coverage Survey). The estimation combines DSE with standard ratio and regression estimation. A simulation study using census data from the 1991 Census of England and Wales demonstrates that the ratio model is in general more robust than the regression model.
Release date: 2000-03-02 - 5. Simultaneous calibration of several surveys ArchivedSurveys and statistical programs – Documentation: 11-522-X19990015684Description:
Often, the same information is gathered almost simultaneously for several different surveys. In France, this practice is institutionalized for household surveys that have a common set of demographic variables, i.e., employment, residence and income. These variables are important co-factors for the variables of interest in each survey, and if used carefully, can reinforce the estimates derived from each survey. Techniques for calibrating uncertain data can apply naturally in this context. This involves finding the best unbiased estimator in common variables and calibrating each survey based on that estimator. The estimator thus obtained in each survey is always a linear estimator, the weightings of which can be easily explained and the variance can be obtained with no new problems, as can the variance estimate. To supplement the list of regression estimators, this technique can also be seen as a ridge-regression estimator, or as a Bayesian-regression estimator.
Release date: 2000-03-02 - Surveys and statistical programs – Documentation: 11-522-X19990015688Description:
The geographical and temporal relationship between outdoor air pollution and asthma was examined by linking together data from multiple sources. These included the administrative records of 59 general practices widely dispersed across England and Wales for half a million patients and all their consultations for asthma, supplemented by a socio-economic interview survey. Postcode enabled linkage with: (i) computed local road density; (ii) emission estimates of sulphur dioxide and nitrogen dioxides, (iii) measured/interpolated concentration of black smoke, sulphur dioxide, nitrogen dioxide and other pollutants at practice level. Parallel Poisson time series analysis took into account between-practice variations to examine daily correlations in practices close to air quality monitoring stations. Preliminary analyses show small and generally non-significant geographical associations between consultation rates and pollution markers. The methodological issues relevant to combining such data, and the interpretation of these results will be discussed.
Release date: 2000-03-02 - Surveys and statistical programs – Documentation: 11-522-X19990015692Description:
Electricity rates that vary by time-of-day have the potential to significantly increase economic efficiency in the energy market. A number of utilities have undertaken economic studies of time-of-use rates schemes for their residential customers. This paper uses meta-analysis to examine the impact of time-of-use rates on electricity demand pooling the results of thirty-eight separate programs. There are four key findings. First, very large peak to off-peak price ratios are needed to significantly affect peak demand. Second, summer peak rates are relatively effective compared to winter peak rates. Third, permanent time-or-use rates are relatively effective compared to experimental ones. Fourth, demand charges rival ordinary time-of-use rates in terms of impact.
Release date: 2000-03-02 - Surveys and statistical programs – Documentation: 11-522-X19980015017Description:
Longitudinal studies with repeated observations on individuals permit better characterizations of change and assessment of possible risk factors, but there has been little experience applying sophisticated models for longitudinal data to the complex survey setting. We present results from a comparison of different variance estimation methods for random effects models of change in cognitive function among older adults. The sample design is a stratified sample of people 65 and older, drawn as part of a community-based study designed to examine risk factors for dementia. The model summarizes the population heterogeneity in overall level and rate of change in cognitive function using random effects for intercept and slope. We discuss an unweighted regression including covariates for the stratification variables, a weighted regression, and bootstrapping; we also did preliminary work into using balanced repeated replication and jackknife repeated replication.
Release date: 1999-10-22 - Surveys and statistical programs – Documentation: 11-522-X19980015029Description:
In longitudinal surveys, sample subjects are observed over several time points. This feature typically leads to dependent observations on the same subject, in addition to the customary correlations across subjects induced by the sample design. Much research in the literature has focussed on modeling the marginal mean of a response as a function of covariates. Liang and Zeger (1986) used generalized estimating equations (GEE), requiring only correct specification of the marginal mean, and obtained standard errors of regression parameter estimates and associated Wald tests, assuming a "working" correlation structure for the repeated measurements on a sample subject. Rotnitzky and Jewell (1990) developed quasi-score tests and Rao-Scott adjustments to "working" quasi-score tests under marginal models. These methods are asymptotically robust to misspecification of the within-subject correlation structure, but assume independence of sample subjects which is not satisfied for complex longitudinal survey data based on stratified multi-stage sampling. We proposed asymptotically valid Wald and quasi-score tests for longitudinal survey data, using the Taylor Linearization and jackknife methods. Alternative tests, based on Rao-Scott adjustments to naive tests that ignore survey design features and on Bonferroni-t, are also developed. These tests are particularly useful when the effective degrees of freedom, usually taken as the total number of sample primary units (clusters) minus the number of strata, is small.
Release date: 1999-10-22 - 10. Estimation with partial overlap longitudinal samples ArchivedSurveys and statistical programs – Documentation: 11-522-X19980015035Description:
In a longitudinal survey conducted for k periods some units may be observed for less than k of the periods. Examples include, surveys designed with partially overlapping subsamples, a pure panel survey with nonresponse, and a panel survey supplemented with additional samples for some of the time periods. Estimators of the regression type are exhibited for such surveys. An application to special studies associated with the National Resources Inventory is discussed.
Release date: 1999-10-22