Keyword search

View results

Filter results by

Search Help
Currently selected filters that can be removed
Remove Remove "Statistical methods" filterRemove Remove "Data analysis" filter
Clear all

Keyword(s)

Subject

Type

1 facets displayed. 0 facets selected.

Year of publication

2 facets displayed. 0 facets selected.
Sort Help
entries

Results

All (2)

All (2) ((2 results))

  • 1. Validation of qualitative methodology applied to a multidimensional instrument with an open question Archived
    Articles and reports: 11-522-X200600110443
    Description:

    The Brazilian population has experienced an ageing process, thus characterizing an increase in the number of elderly people. Instruments have been developed in order to measure the quality of life of elderly individuals. Hence, a questionnaire consisting of various validated instruments and an open question was applied to a group of elderly citizens in the city of Botucatu, SP, Brazil. The analysis of the open question, assessed by qualitative methods, generated eleven categories concerning the elderly people's opinions as regards quality of life and a cluster analysis of such answers was carried out, producing three groups of elderly individuals. Therefore, this work aimed at validating the categories obtained by the open question with the closed questions of the instrument by means of associations and application of chi-square tests at a level of significance of 5%. It was observed that qualitative analysis identifies phenomena regardless of category saturation. The quantitative method, on the other hand, shows the power of each category in a set, that is, as a whole.

    Release date: 2008-03-17
  • 2. Application of the delete-a-group jackknife variance estimator to analyses of data from a complex longitudinal survey Archived
    Articles and reports: 11-522-X20020016714
    Description:

    In this highly technical paper, we illustrate the application of the delete-a-group jack-knife variance estimator approach to a particular complex multi-wave longitudinal study, demonstrating its utility for linear regression and other analytic models. The delete-a-group jack-knife variance estimator is proving a very useful tool for measuring variances under complex sampling designs. This technique divides the first-phase sample into mutually exclusive and nearly equal variance groups, deletes one group at a time to create a set of replicates and makes analogous weighting adjustments in each replicate to those done for the sample as a whole. Variance estimation proceeds in the standard (unstratified) jack-knife fashion.

    Our application is to the Chicago Health and Aging Project (CHAP), a community-based longitudinal study examining risk factors for chronic health problems of older adults. A major aim of the study is the investigation of risk factors for incident Alzheimer's disease. The current design of CHAP has two components: (1) Every three years, all surviving members of the cohort are interviewed on a variety of health-related topics. These interviews include cognitive and physical function measures. (2) At each of these waves of data collection, a stratified Poisson sample is drawn from among the respondents to the full population interview for detailed clinical evaluation and neuropsychological testing. To investigate risk factors for incident disease, a 'disease-free' cohort is identified at the preceding time point and forms one major stratum in the sampling frame.

    We provide proofs of the theoretical applicability of the delete-a-group jack-knife for particular estimators under this Poisson design, paying needed attention to the distinction between finite-population and infinite-population (model) inference. In addition, we examine the issue of determining the 'right number' of variance groups.

    Release date: 2004-09-13
Data (0)

Data (0) (0 results)

No content available at this time.

Analysis (2)

Analysis (2) ((2 results))

  • 1. Validation of qualitative methodology applied to a multidimensional instrument with an open question Archived
    Articles and reports: 11-522-X200600110443
    Description:

    The Brazilian population has experienced an ageing process, thus characterizing an increase in the number of elderly people. Instruments have been developed in order to measure the quality of life of elderly individuals. Hence, a questionnaire consisting of various validated instruments and an open question was applied to a group of elderly citizens in the city of Botucatu, SP, Brazil. The analysis of the open question, assessed by qualitative methods, generated eleven categories concerning the elderly people's opinions as regards quality of life and a cluster analysis of such answers was carried out, producing three groups of elderly individuals. Therefore, this work aimed at validating the categories obtained by the open question with the closed questions of the instrument by means of associations and application of chi-square tests at a level of significance of 5%. It was observed that qualitative analysis identifies phenomena regardless of category saturation. The quantitative method, on the other hand, shows the power of each category in a set, that is, as a whole.

    Release date: 2008-03-17
  • 2. Application of the delete-a-group jackknife variance estimator to analyses of data from a complex longitudinal survey Archived
    Articles and reports: 11-522-X20020016714
    Description:

    In this highly technical paper, we illustrate the application of the delete-a-group jack-knife variance estimator approach to a particular complex multi-wave longitudinal study, demonstrating its utility for linear regression and other analytic models. The delete-a-group jack-knife variance estimator is proving a very useful tool for measuring variances under complex sampling designs. This technique divides the first-phase sample into mutually exclusive and nearly equal variance groups, deletes one group at a time to create a set of replicates and makes analogous weighting adjustments in each replicate to those done for the sample as a whole. Variance estimation proceeds in the standard (unstratified) jack-knife fashion.

    Our application is to the Chicago Health and Aging Project (CHAP), a community-based longitudinal study examining risk factors for chronic health problems of older adults. A major aim of the study is the investigation of risk factors for incident Alzheimer's disease. The current design of CHAP has two components: (1) Every three years, all surviving members of the cohort are interviewed on a variety of health-related topics. These interviews include cognitive and physical function measures. (2) At each of these waves of data collection, a stratified Poisson sample is drawn from among the respondents to the full population interview for detailed clinical evaluation and neuropsychological testing. To investigate risk factors for incident disease, a 'disease-free' cohort is identified at the preceding time point and forms one major stratum in the sampling frame.

    We provide proofs of the theoretical applicability of the delete-a-group jack-knife for particular estimators under this Poisson design, paying needed attention to the distinction between finite-population and infinite-population (model) inference. In addition, we examine the issue of determining the 'right number' of variance groups.

    Release date: 2004-09-13
Reference (0)

Reference (0) (0 results)

No content available at this time.

Report a problem or mistake on this page
Date modified:

Search help

How do I use the filters and the search box?

  • You can initiate a search by entering keywords or selecting filters (e.g., under Subject, Geography, etc.) on the left side of the page.

  • Filters can be used together or in any combination. Each time you select a filter, the results on the page are updated.

  • To start a new search, click on the Clear all button above the search box or deselect each filter.

  • Specified keywords and filters appear above the search box. You can deselect any or all the tags to refine or clear your search.

How do I refine my search?

  • You can enter keywords in the search box. It is not necessary to use “+” or “, “ or “AND”.

  • You can delete some or all of the keywords from your search string.

  • Quotes around keywords limit the search to a specific phrase.

    • For example, “labour force survey” will limit results to products containing this phrase.

  • Use “or” between keywords to obtain results that contain one or more search terms.

    • For example, labour or­ force or survey will limit results to products containing any or all of these words.

How does the search work?

  • This search looks for results that have your query term in the title, description, subject, geography, product number or other information about the product.

    • For example, when searching the term ‘Diseases’, all results with the word ‘Diseases’ in the title, description or tagged the subject appear.

  • The text within an article or publication are not searched. For full text searching of articles, use the site search.

Sort help

How are the results ordered?

The Sort by feature provides three options:

  • By date – sorts results by product release date starting with the most recent.
  • By relevance is only needed or beneficial when you use the search box and submit a search query. Results are ordered by a combination of where the search term appears in the content, e.g., if it appears in the title, it likely means the product is more relevant to your search; how up to date or new the content in the product is; how popular the product is; and other factors.
  • By title – sorts results alphabetically.

Sort help

How are the results ordered?

The Sort by feature provides four options:

  • By date – sorts results by product release date starting with the most recent.
  • By most popular – gives priority to results that are most frequently selected by users, followed by the most recent.
  • By relevance is only needed or beneficial when you use the search box and submit a search query. Results are ordered by a combination of where the search term appears in the content, e.g., if it appears in the title, it likely means the product is more relevant to your search; how up to date or new the content in the product is; how popular the product is; and other factors.
  • By title – sorts results alphabetically.