2DBCB771206506B6E040CD9B0F274EFEEnglishAUSLIG (Australian Survey and Land Info Group)AUSLIG Data Sales02 6201 434002 6201 4381datasales@auslig.gov.au2000-01-14AS/NZS ISO 19115 Geographic Information - Metadata, ANZLIC Metadata Profile1.0Geodata Topo-250k (Series 2) Topographic Data2000-01-14ANZNT0001000278Contains a medium scale vector representation of the topography of Australia. The data include the following themes: Hydrography - drainage networks including watercourses, lakes, wetlands, bores and offshore features; Infrastructure - constructed features to support road, rail and air transportation as well as built-up areas, localities and homesteads. Utilities, pipelines, fences and powerlines are also included; Relief - features depicting the terrain of the earth including 50 metre contours, spot heights, sand dunes, craters and cliffs; Vegetation - depicting forested areas, orchards, mangroves, pine plantations and rainforests; and Reserved Areas - areas reserved for special purposes including nature conservation reserves, aboriginal reserves, prohibited areas and water supply reserves.The data are subject to Commonwealth of Australia Copyright. A licence agreement is required and a licence fee is also applicable. English-27.000003-10.949999127.156465139.712224datasetnot knownAll instances of a feature and its attribute values that appear on the source material are captured unless otherwise indicated in the selection criteria for that feature. 0not knownValidating logical consistency may involve tests to check that table and file names are set out as in the Data Dictionary. Also included are graphical tests which check such things as intersections, polygon closure, minimum sizes of polygons and topological relationships. The allowable error in logical consistency ranges from 0% to 5%. Further information on the validation and testing methodology used by AUSLIG can be found in section 3 of the TOPO-250K GEODATA Specifications. 0not knownAUSLIG has carried out both error budget analysis and field tests to verify the positional accuracy of the data. TOPO-250K Series 2 data complies with the following statement of horizontal accuracy: "The summation of errors from all sources results in data with a standard deviation of 85 metres for well defined features". Alternative and equal ways of expressing this error are: Not more than 10% of well-defined points are in error by more than 140 metres; and In the worst case, a well defined point is out of position by 300 metres. As the TOPO-250K Series 2 data were digitised from existing map production material, some features may be subject to cartographic displacement. A full description of the features that may have been displaced and the range of displacement that may have occurred due to generalisation are provided in the TOPO-250K Series 2 Data Quality Statement supplied with the data. An estimate of the standard deviation of planimetric error of each feature instance is given in the Data Quality Table. Vertical Accuracy: The accuracy of the spot elevations in the relief layer varies with the type of source material from which they were captured and the point determination for each particular point. Most spot heights have an accuracy of + or - 5 metres, however bench marks and horizontal control points have an accuracy of + or - 1 metre. The accuracy of contours is defined as 1/2 of the contour interval, for example + or - 25 metres for a 50 metre contour interval. 0not knownATTRIBUTE ACCURACY: For the TOPO-250K product, attribute accuracy is a measure of the degree to which the attribute values of features agree with the information on the source material. The allowable error in attribute accuracy ranges from 0.5% to 5%, at a 99% confidence level. Where less than 1% of attribute errors are permissible the entire population is tested. Where a less stringent limit is set for allowable errors a random subset of the relevant features in the tile is generally tested. The sample size is determined from statistical tables using the known population size of the relevant feature. Further information on the validation and testing methodology used by AUSLIG can be found in section 3 of the TOPO-250K GEODATA Specifications. 0TOPO-250K Series 2 is primarily sourced from TOPO-250K Series 1 and 1:250 000 scale map reproduction material (from the National Topographic Map Series and Defence Joint Operation Graphics). A key revision source for the data is satellite imagery taken from the SPOT Panchromatic and LANDSAT Thematic Mapper Sensors. Revision material has also been gathered from a variety of authoritative sources. More information about the sources for this data can be found in AUSLIG's Topographic Data and Map Specifications.