Note: This is a revised version of the orginal tutorial. We have created smaller modules this time and are now using a more compact video format (mp4). Hopefully, this will address the problems we had with some browsers taking a very long time to load the .avi video modules in the earlier version. In terms of content, we have removed all the extra background regarding the data archive and uexplore (in the first video module). It was usefule information but it really does not need to be included in an introductory tutorial about how to use Dexter.
This tutorial consists of a collection of video modules where we cover more or less the same material that you can see in the Dexter Quick Start Guide. The difference is in the media. In the Guide you view static screen shots of web pages and you read the explanatory text. But here you get to actually see what the Guide just described. Just click on the underlined links to view the video modules. You'll need to have a browser that has been configured to invoke a plug-in module that can play mp4 video files (for most IE users the obvious choice is Windows mediaplayer). Note that some of the video files are still somewhat large and may take a minute or two to download and begin playing.
This is a brief introduction and overview to the MCDC's Data Archive system, showing how the user can navigate thruough the data files using Uexplore and arriving at the Dexter query form. It shows access via the Uexplore/Dexter home page as well as direct links from a custom application and via an article on our Whatsnew page.
Section II is where we spend our most time, building a series of relatively simple filters based on geographic codes primarily. It's a bit long, but you are not required to watch the entire thing.
We have several examples here. They vary in complexity according to the complexity of the datasets being accessed.
We access a small dataset in our georef collection. We generate a report with all available data and then refine it by selecting just the ones we really want to see.
We access a typical dataset in our American Community Survey standard profile data collection. We generate an extract with variables related to a specific topic (poverty) making use of the ability to specify a variable filter to shorten the numeric variables select list.
Some of our datasets are what the Census Bureau refers to as "Summary Files", which are organized into tables. These include the ACS "base tables" datasets and the various decennial census summary files. In order for a dataset to be accessible at the table level rather than by variable some special metadata files need to be created and the Dexter software tweaked so that it recognizes a table-based set. In this example we shall be accessing one of the datasets from the 2000 Census, Summary File 3 collection. We include a quick visit to the relevant Varlabs data dictionary files that can brose to see what kind of tabular data are available.
We do not have any modules here relating to these two sections of the Dexter query form. This tutorial is labeled a "Quick Start Guide" to indicate that it is an introduction to the topic. Hence we have omitted the Advanced Options of Section V. Section IV is omitted because it is too trivial to merit any further explanation. We plan to create other companion tutorials that will cover Section V, as well as the rankster post-processor and other intermediate or advanced features.