A codebook documents basic information about a data set and its variables. Viewing the codebook for a data set will help you identify variables of interest and determine which variables to analyze.
Every NACJD study has a downloadable PDF codebook that describes the data, provides variable frequencies, and discusses the study methodology.
Online SDA codebooks provide quick access to a brief description of the data set and allow you to quickly browse through the variables available for online analysis. We will now examine the various parts of the SDA codebook for Capital Punishment in the United States, 1973-2004.
The codebook information for the CAPITAL PUNISHMENT IN THE UNITED STATES, 1973-2004 study includes the following links in the vertical panel to the left of the main codebook page:
The number and type of codebook links may vary somewhat from one data set to the next - for example, many codebooks include a Codebook Note and/or a Confidentiality Protection link.
When you select links for the CAPITAL PUNISHMENT IN THE UNITED STATES, 1973-2004 study, the target of each link opens in the main codebook window. Meanwhile, the vertical panel on the left remains accessible so that you can easily follow another link.
The codebook information should always be reviewed before performing any analysis to determine whether there is important information about such issues as weighting or sample design.
The links under the Variable List heading of the vertical panel on the left side of the main codebook window take you to lists of the data set variables.
Group Headings. All NACJD data sets have an option called Group Headings that organizes the variables into logical groups that can be browsed.
When you select the Group Headings link for the CAPTIAL PUNISHMENT IN THE UNITED STATES, 1973-2004 study, a list of the Group Headings will appear in the main codebook window. For this data set, all of the variables have been organized into 5 variable groups. Some data sets require the use of both headings and subheadings in order to better organize a large number of variables.
When you select one of the heading links in the main codebook window, the Standard Variable List will open. Additionally, you will see the list of variables that fall under the heading you selected.
Standard Variable List. The Standard Variable List displays the variables in order of appearance in the codebook. When you select the link for the Standard Variable List, it will list all of the variables in the data set organized by the Group Headings.
When you select one of the variable links now appearing in the main codebook window, the Variable Description will appear.
Alphabetical Order. All NACJD data sets have a variable index called Alphabetical Order. This index is useful if you know the name of a variable and you want to find that variable quickly.
This index is also useful if the names of the variables are words related to the content of the variables (like AGE or RACE).
Now we will look at a Variable Description of the variable MARITAL STATUS.
To find the Variable Description for MARITAL STATUS, select the Standard Variable list and then select V16.
Once you get to the Variable Description, you will generally find the following information:
Once you have identified the variables of interest for a data set, you can run various analyses on the data.
The next section focuses on running frequencies and crosstabulations.
Continue to the Frequency / Crosstabulation Tutorial