Documenting Columns in a Data Set

Documenting Columns

Once you've uploaded a dataset, you need to document each of the columns.  Documenting columns helps users in the future to understand the data within each column, and to decode any coded values. To access the columns in a data set click "Table Metadata" in the view page toolbar.

Choosing a Column Type:

tDAR includes five separate column types:

• Numeric value - a numeric value, such as an ID number count, or measurement that stands on its own
• Text value - a text value that stands on its own, such as a provenience label, a comment or a variable state (e.g. "jar") that is entered n a textual form (note that in databases, text values are case sensitive so "jar" is not the same as "Jar".)
• Coded value - numeric or text codes that use a coding sheet to translate to a human-readable label (if you mark a column as having a coded value, tDAR will prompt you to select the coding sheet)
• Measurement - column contains litres, pounds, inches, etc
• Count - the value is a number but represents a count of some other column

Why are some of these values filled in automatically?

tDAR tries to identify the contents of columns for you if possible.  This includes looking to see if the contents include text or numeric data.  If they do, it will set defaults for you.

Categorizing your data:

Chose a category from the drop down menus that best describes your data (Architecture, Ceramics, Provenience and Context, etc.).

Providing a description:

Often it's helpful to other users to have a sentence long description of a column's contents.

Choosing a Coding Sheet

If you've marked a column as including coded data, tDAR will allow you to select the coding sheet that contains that coded data.  If you've already loaded the coding sheet, you can simply start typing the name of the coding sheet in the coding sheet section, otherwise click "add new"to create one. (note: you'll need to save this page and reload for tDAR to find it).

Choosing an Ontology

Not all columns need ontologies assigned.  Ontologies allow you to organize data within a column hierarchically (eg: Furniture > Chairs > Rocking Chair ). This is often useful in data integration when comparing multiple data sets that different levels of specificity.  If you've already loaded the ontology, you can simply start typing the name of the ontology in the ontology section, otherwise click on the link to the left to create one. (note: you'll need to save this page and reload for tDAR to find it).