Use these tutorial steps to keep the NLS software in your browser in synchronization
with these manual pages.
Follow along, by following these examples.
The main application of the NLS Web-Investigator software is to access survey dependent variables for the purposes of identifying them, selecting them, extracting them, weighting them, and/or running a frequencies or cross-tab on them. The first step in selecting variables is to select the cohort, i.e., the survey, in which they were collected.
| Sample Tutorial: Use these tutorial steps to keep the NLS software in your browser in synchronization with these manual pages. Follow along, by following these examples. |
When the use clicks on the Web Investigator button the following page appears. This page is the first step to data access, the use must first select a cohort, so that the software can access the right database. This page displays the starting point for new session: Cohort selection. If a cohort is already selected, clicking on the Web Investigator button will display the beginning page for variable(s) investigation in the selected cohort shown in the second figure below.
| Choose a Cohort: Choose, "National Longitudinal Survey of Youth 1979". Click on, "Open Cohort". |
After the user has selected a cohort and pressed the "Open Cohort" button, the Web-Investigator will display the beginning page for variable(s) investigation in that cohort. If a cohort has already been chosen, clicking on the Web Investigator button will display the same, beginning page for variable(s) investigation in that cohort.
The figure below shows "filter selection" page on which the user can begin to narrow the choice of variables. The tutorial example is using the "National Longitudinal Survey of Youth 1979" cohort.
If National Longitudinal Survey of Youth 1979 is not the cohort listed next to Web-Investigator - at the top of the page, the user may change the cohort by selecting the desired cohort from the Select a Different Cohort drop-down menu.
With the desired cohort selected, the user must now begin adding filters by choosing items from indices that will narrow the focus on variables to be investigated. The indices are listed below in bold in a column beginning with Word in Title and ending with Optional. Adjacent are the filter categories in the form of input fields. For an overview of the indices, click on indices.
What filters do:
Now let's add a filter to narrow the focus of the variables by choosing a term from the Area of Interest index.
| Area of Interest: In the Area of Interest drop-down field, choose "COMMON". (Scroll down to "COMMON", or type the letter "c", then scroll.) |
When a filter has been chosen and the Submit Filter Choice(s) button pressed, the resulting variables retrieved will be displayed on a single Web page in ascending order by Name (R-number). The length of the page will depend on the number of filters applied and the number of variables retrieved. Note on the page shown below in the "Filters Applied [hint]" section, the chosen filter will appear (along with any filters kept) and below that the resulting individual variables will be listed under the number of "variable records" retrieved. If the filter used resulted in usable variables, the filter may be kept by clicking in the box labelled "Keep filter?". If the box is not checked, the filter will not be used in subsequent searches. Tagged variables, however, will be retained.
| Filter(s) Applied: Do not keep this filter, so do not check the "Keep filter?" next to COMMON box |
Be sure to scroll down through the list of COMMOM variables to the bottom of the Web page. Buttons to manage the retrieved variables follow the list of variables. As you scroll down you may investigate a variable by looking at its "variable title". If a variable looks interesting or useful you can find out more about it by clicking on the variable's name in the "Name" column. The variable's name is a link to the 3.8 Codebook which contains more detailed information about the variable.
| 70 Variable Records: Click here on R0000100 to see the codebook information on the variable (R0000100 CASEID IDENTIFICATION CODE 1979). |
Variables may also be sorted by clicking on one of the column headings: Name, Question, Variable Title, and Year. Sorting variables by a category such as Year, Variable Title, or name of the Question in which they were used may group them in a way that helps investigation. For example, grouping them by Variable Title will bring like-variables together (see NUMBER OF WEEKS...). Grouping them by Question name may show which variables were created (see *Created) and which were used in a question; it may also show in which survey section the variable was collected and thereby help in including or excluding variables from certain sections (see RNI). Sorting by Year may also show when a variable appears or disappear in the life of the survey and/or when the variable passes from one that was created retrospectively to one that becomes a question in itself (see REASON FOR NONINTERVIEW).
| Variables Tagged: In the list of variables, tag the following four: #1. CASEID; #2. HOUSEHOOD IDENTIFICATION NUMBER; #14. R'S RACIAL/ETHNIC COHORT FROM SCREENER; #15. SEX OF R |
Let's isolate just the variables that were tagged for review. See the image below.
| Review Tagged Variables: Click on the Review Tagged Variables button |
When the Review Tagged Variables button is pressed, just the variables saved are displayed and the "Review Tagged Variables" button now changes to "Update Tagged Variables". The 'update' button is the same as the 'review' button in that it allows the user to add filters to the tag set.
In order to perform statistical functions on the data, they must first be extracted from the data set. To extract data, a set of variables must be tagged, then an extract can be run using the Extract Tagged Variables button shown above. A group of tagged variables can also be placed into a file called a "tag set" and saved on the user's PC for future use. Multiple tag sets may be created and saved by the user. Tag sets are saved using the Tag Set Maintenance functions shown above.
For now, let's save the set of tagged variables just created above and run the extract later. You could extract the data now without saving the variables to a file, but unsaved variables will be lost when the session ends.
| Tag Set Maintenance: Click in the Tag Set Name field to place the cursor there and type in the tag set name; e.g., "4_common_vars" without the quotes. Click on the Save Tag Set button and two standard Windows dialogue boxes will appear: 1. Warning about downloads from the Web to your PC (click on "Save"); and 2. Asking you to locate the folder where the file will be saved. Locate it and click on "Save". |
Tag Set Delivery
If you forget to name a tag set and save it, and you extact variables, the file created will be named "default-uniq_char_seq_encrypt_all"; given the extension ".zip"; and be delivered to your account with that name. Otherwise, the file will be named "tag-set-name-uniq_char_seq_encrypt_all.zip" and delivered to your account (7.0 My Account: 7.4 Account Deliveries).
If you run a frequency or cross-tabulation the file created will be named "default-uniq_char_seq_encrypt" and delivered to your account with that name. Otherwise, it will be named "tag-set-name-uniq_char_seq_encrypt and delivered to your account (7.0 My Account: 7.4 Account Deliveries) from where you can view it in a browser as html or as text.
If you already had a tag set file saved and wanted to open it, you would use the Open a Saved Tag Set field, Browse your PC for the file, and click on Open after locating it.
Go to 3.6 Extract Tagged Variables.
Go to 3.7 Run a Frequency of Table.
Go back to the Table of Contents.