4720.0.55.002  Microdata: National Aboriginal and Torres Strait Islander Social Survey, 201415 Quality Declaration
Latest ISSUE Released at 11:30 AM (CANBERRA TIME) 27/05/2016 First Issue
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FILE STRUCTURE
Broadly, each level provides the following:
An additional level (2. All persons in household) was created for processing purposes, including family coding and calculating household income. Data from this level is not available for output. General Social Survey (NonIndigenous) — (TableBuilder only) The 2014 General Social Survey (NonIndigenous) (2014 GSSNI) TableBuilder is constructed as a subset from the 2014 General Social Survey (GSS) TableBuilder, which has been modified to reflect the NATSISS file structure and comparable data items. This will enable comparisons between Aboriginal and Torres Strait Islander and nonIndigenous social outcomes using 2014–15 NATSISS and 2014 GSSNI data. As a modified version of the GSS TableBuilder file, The 2014 GSSNI TableBuilder file contains the following key features:
For further information regarding the GSS TableBuilder see Microdata: General Social Survey, Australia, 2014 (cat. no. 4159.0.30.004). Weights and estimation As the NATSISS survey was conducted on a sample of households in Australia, it is important to take account of the method of sample selection when deriving estimates. This is particularly important as a person's chance of selection in the survey varied depending on the state or territory in which they lived. Survey 'weights' are values which indicate how many population units are represented by the sample unit. There are two survey weights provided: a person weight (ISSFINWT) and a household weight (HHFINWT). These should be used when analysing data at the person and household level respectively. Where estimates are derived, it is essential that they are calculated by adding the weights of person or households, as appropriate in each category, and not just by counting the number of records falling into each category. If the 'weight' of each person or household were to be ignored, then no account would be taken of a person or household's chance of selection in the survey or of different response rates across population groups, with the result that counts produced could be biased. The application of weights ensures that person and household estimates conform to an independently estimated distribution of the population by state, remoteness, age, sex and remote community status. General Social Survey (NonIndigenous) — (TableBuilder only) For the 2014 GSSNI TableBuilder, weights for applicable household, person and access to services level records were retained from the GSS Tablebuilder. For information about weighting of the GSS file, see the File structure page from Microdata: General Social Survey, Australia, 2014 (cat. no. 4159.0.30.004). Counting units and weight The counting unit for NATSISS level one is the household, for level three the person, for level four barriers to services. There is a weight attached to each level in order to estimate the total population of the respective counting unit. The weight on level one is the household weight, and the weight for levels three and four is the person weight. What you count depends on the level from which you select the weight. A household level weight estimates the number of households with a particular characteristic. Likewise the weight included in the person level estimates the number of persons with the selected characteristics. Replicate weights have also been included and these can be used to calculate the standard error. For more information, refer to the Standard Errors section below. General Social Survey (NonIndigenous) — (TableBuilder only) For the 2014 GSSNI TableBuilder, counting units and weights were retained from the GSS TableBuilder. For information about weighting of the GSS file, see the File structure page from Microdata: General Social Survey, Australia, 2014 (cat. no. 4159.0.30.004). Standard errors Each NATSISS record on the household level and person level also contains 250 replicate weights and, by using these weights, it is possible to calculate standard errors for weighted estimates produced from the microdata. This method is known as the 250 group deleteagroup jackknife variance estimator. Under the deleteagroup jackknife method of replicate weighting, weights were derived as follows:
Replicate weights enable variances of estimates to be calculated relatively simply. They also enable unit record analyses such as chisquare and logistic regression to be conducted, which take into account the sample design. Replicate weights for any variable of interest can be calculated from the 250 replicate groups, giving 250 replicate estimates. The distribution of this set of replicate estimates, in conjunction with the full sample estimate, is then used to approximate the variance of the full sample. The formulae for calculating the Standard error (SE) and Relative standard error (RSE) of an estimate using this method is shown below. RSE(y) = SE(y)/y*100 where: g = (1, ..., 250) (the number of replicate weights) y(g) = estimate from using replicate weighting y = estimate from using full person weight. The deleteagroup jackknife method can be applied not just to estimates of the population total, but also where the estimate y is a function of estimates of the population total, such as a proportion, difference or ratio. For more information on the deleteagroup jackknife method of SE estimation, see Research Paper: Weighting and Standard Error Estimation for ABS Household Surveys (Methodology Advisory Committee), July 1999 (cat. no. 1352.0.55.029). Use of the 250 group deleteagroup jackknife method for complex estimates, such as regression parameters from a statistical model, is not straightforward and may not be appropriate. The method as described does not apply to investigations where survey weights are not used, such as in unweighted statistical modelling. General Social Survey (NonIndigenous) — (TableBuilder only) For the 2014 GSSNI TableBuilder, the weighting methodology was retained from the GSS TableBuilder. The main difference from the NATSISS being that the 2014 GSSNI contains 60 replicate weights. For information about weighting of the GSS file, see the File structure page from Microdata: General Social Survey, Australia, 2014 (cat. no. 4159.0.30.004). Document Selection These documents will be presented in a new window.
