Overview of Tools for the Public

LI GIS Maps Overview

The LI GIS Maps provide an Internet mapping facility for the public. They were created to give the public a window into how a GIS works. Visitors can see, and use, some of the content and features of the LI GIS for researchers without needing special computer skills. Visitors may choose from a list of pre-constructed web maps available on the web site and search areas in Long Island for breast cancer rates, hazardous waste sites, and pesticides detected.

The LI GIS maps for the public do not provide insight on an individual's breast cancer risk (the estimated chance of getting a disease during a certain time period). These maps do not provide all of the statistical tools and all of the scientific information necessary to determine possible health implications or disease risk. In addition, cancer risk depends on many things, including lifestyle (e.g. tobacco use, diet), family history, and contact with cancer-causing substances. Also, these maps illustrate variations in breast cancer incidence (new cases) by ZIP Code during 1993-1997 and do not represent current breast cancer rates.

Interactive Maps

Each map is designed with a standard set of map tools and data tools that will allow the user to alter the look of the map or query the data associated with the map.

The best way to learn how to work with the web maps is to 1) Tour the LI GIS Tutorial; 2) Select a map and begin to experiment with the various tools (displaying the layers, zooming in and out, searching, panning around the map, identifying objects). Please click here to access the interactive maps.

Privacy

The LI GIS data are stored in the LI GIS data warehouse. Map content is restricted only to LI GIS data that are approved for public dissemination. Data that are subject to privacy restrictions and/or intended only to be used in a secure environment by researchers will not be displayed on the web or be made available through map services.

Map terms that you need to be familiar with in using web maps and services:

Map Layer: A spatial dataset containing a common feature type. Layers are also referred to as coverages or themes.
Active layer: The query, search, and identify tools all return data from the active layer. Only one layer can be specified as active at a time.
Visible layer: Layers may be turned on or off. Visible layers will be shown on the map.
Query: The process of selecting information from a GIS by asking spatial or logical questions of the geographic data. Spatial query is the process of selecting features based on location or spatial relationship (e.g., select all features within 300 feet of another; point at a set of features to select them). Logical query is the process of selecting features whose attributes meet specific logical criteria (e.g., select all polygons whose value for AREA is greater than 10,000 or select all streets whose name is 'Main St.'). Once selected, additional operations can be performed, such as drawing them, listing their attributes or summarizing attribute values.
Identify: This function allows you to click on the map and have data returned about that feature of the active layer.
Buffer: A zone of a specified distance around a selected feature. The resulting buffer zones form polygonal coverages.
Pan: This function gives you the ability to manually move a map in any direction but does not change the map extent.
Zoom: This function gives you the ability to change the map extent. You may zoom in or zoom out.
Map Services: A map service is a grouping of layers. These layers typically will have a common theme. Map services may contain just one layer.