Committee on Institutional Cooperation Government Documents Task Force

NELS:88 Electronic Codebook System (ECB)

User's Guide
Fall 1994 Public and Restricted Versions of the NELS:88
Base Year Through Second Follow-Up Data Files on CD-ROM

1. Contents of the Fall 1994 NELS:88 CD-ROM

Altogether users will find 36 files on the public and restricted versions of the 1994 fall NELS:88 BY-F2 CD-ROM. The root directory contains the following two files:

• \README.1ST -- instructions for installing the ECB system on a PC
• \ECBGUIDE.WP5 -- the NELS:88 ECB Guide for installing and operating the ECB system on the fall 1994 NELS BY-F2 CD-ROM.

The remaining files appear in the following three subdirectories:

• \ECB\ -- contains all of the files needed to run the ECB;
• \DOCU\ -- contains all of the data file users manuals that document NELS:88;
• \DATA\ -- contains the 15 data files that comprise the NELS:88 BY-F2 dataset

As the subdirectory listing above indicates, three types of files appear on this CD- ROM. First, files that operate the ECB program are organized under subdirectory "\ECB". These are listed in the next section of this guide--installation and operation of the NELS:88 ECB system. Second, the CD includes WordPerfect text files of data file user manuals. These WordPerfect text files contain detailed information on the design and conduct of each of the NELS:88 surveys. Data file users manuals appear in the "\DOCU" subdirectory. Third, included in the subdirectory "\DATA" are the 15 data files that make up the NELS:88 BY-F2 public and restricted datasets (more information on these data files and the difference between public and restricted CDs is provided in Appendix A, Difference Between the Fall 1994 NELS:88 BY-F2 ECB/CD-ROM and the December 1993 NELS:88 BY-F2 Interim ECB/CD-ROM).

1.1 NELS:88 Data File User Manual Files--"\DOCU"

Information about the purposes of the study, the data collection instruments, the sample design, and data collection and data processing procedures, used in the base year, first follow-up and second follow-up is presented in the data file users manuals. A data file users manual has been produced for each component survey conducted within each wave of the NELS:88.

The data file users manuals appear on both the public and restricted CDs as WordPerfect text files. It is important to note that these WordPerfect documents have been stripped of all figures and tables that were not produced in WordPerfect. As such, the data file users manuals are not exact replicates of hardcopy versions of the data file users manuals that users can, and should, obtain directly from NCES. You may obtain one or more of the bound data file users manuals, complete with all tables, by contacting Peggy Quinn at NCES (202/219-1743).

Each of these data file users manuals fully explain the background, study design and interrelationships among survey components (such as base year school, first follow-up dropout, or second follow-up parent component of NELS:88). Appropriate use of the thousands of NELS:88 variables requires a thorough knowledge of sampling, data collection and processing methods. The NELS:88 Second Follow-up Student Data File User Manual is the most exhaustive source and is recommended as the best place to begin. It has been expanded since initial release on the 12/93 NELS:88 ECB/CD. A Guide To Using NELS:88 Data is an extremely useful document on the special characteristics of this longitudinal database. The "Guide" is unique in that it contains hints and practical advice on how to appropriately utilize NELS:88. This guide can be obtained by contacting Peggy Quinn at NCES (202-219-1743). Ongoing reference to these and other NELS:88 manuals, depending on the data files that your research requires, is fundamental to analyses of NELS:88.

Table 1.1 Displays the names of the NELS:88 data file users manuals that are in the documentation directory ("\DOCU") on this CD. All of the second follow-up users manuals are in WordPerfect 5.1/Courier 10 font. The base year and first follow-up users manuals are in Wordperfect 5.1/courier 12 font. Users who wish to copy and/or print data file users manual files from the CD can use Table 1.1 to select the file names for the NELS:88 components with which they plan to work.

HINT: The NELS:88 Second Follow-up Student Data File User Manual is the most exhaustive source and is recommended as the best place to begin.

Table 1.1 File Names for NELS:88 Data File User Manuals on Compact Disk (organized in \DOCU Subdirectory).

NELS:88 DATAFILE USER MANUAL COMPONENTS IN \DOCU

1.2 NELS:88 Raw Data Files--"\DATA"

The tables below display basic information on the data files that appear on the NELS:88 BY-F2 CDs. The names of the raw data files for each NELS:88 component as well as the number of cases and the number of variables on each file are provided for both the public version (in Table 1.2a) and the restricted version (in Table 1.2b). If you have not been licensed by NCES to view sensitive data, you have the public version and should refer to Table 1.2a. (If you are interested in obtaining a license, please contact Alan Moorehead at NCES: 202/219-1920).

Please note too that the order in which each component is listed in the tables below is the same order in which the ECBs present information on the survey components: student ("st" in the filename), dropout ("do"), school ("sc"), parent ("pa") and teacher ("te") and within each of these respondent categories, the survey wave in which the data were collected ("by" in the file name = Base Year = 1988; "f1" = First Follow-up = 1990; "f2" = Second Follow-up = 1992).

Table 1.2a Public-Use Version of NELS:88 Datasets, in Subdirectory \DATA.

* These raw data components are divided into two parts (files) because the combined record length exceeds SPSS limits for a single file.

Taken together, the total amount of space that is required, if you wish to copy the 15 public-use data files to, for example, a hard-disk, is 164.1 Megabytes. The total number of variables on the public- use files is 6,334.

* These raw data components are divided into two parts (files) because the combined record length exceeds SPSS limits for a single file.

** The number of cases has been rounded to the nearest 100th as a confidentiality safeguard.

Taken together, the total amount of space that is required, if you wish to copy the 15 restricted- use datasets is approximately 164.9 Megabytes. The total number of variables on the restricted-use files is 6,487.

Tables 1.2a and 1.2b also show how the number of cases on each of the files varies by NELS:88 component, as well as between the public version and the restricted version -- more cases appear on the latter. Whether your analysis involves only one data file or several, either cross-sectionally or over more than one point of time, use of the correct case selection flags is crucial (more on case selection flags for specific NELS:88 analytical populations is provided in Appendix B).

It is worth restating that the number of cases listed in the tables above is especially important for veteran NELS:88 users to notice -- older versions of the first follow-up datasets did not include the Base Year Ineligible Study sample members (BYIs) who became eligible for NELS:88 during the first follow- up and did include students who have since been designated as ineligible for inclusion on the first follow- up student data file (for example, students who were freshened in the fall of 1989, but by spring of 1990 had dropped out of school). The Ns in the tables above represent the net effects of both additions and deletions to the number of cases appearing on previous releases of the first follow-up student data file and dropout data file.

http://www.lib.umich.edu/govdocs/cicdoc/nels88/nels88b.htm