Data Management Forms General Information

Data Management Forms General Information

This package contains a copy of adocumentation (metadata) form that is required to file a data set with the Data Manager. The form is available in a MS Word format on the Web site or hardcopy (please contact LUQ LTER Information Manager.

When first developed, the metadata elements where separated into three different documentation forms: the data set, the data file and the data variables documentation forms. Since year 2000 all three forms where merged into one, containing the same metadata elements as before and more and is available now in the formats mentioned above.

The following discussion of these different forms still apply to the present form since it the concepts are the same:

Data Set Documentation Form ⁽²⁾.

This form must be submitted with the first data file given to the Data Manager. Investigators are responsible for completing this form properly. The form gathers general information of the complete data set. The investigators must follow the following guideline to organize their data in different files:

A DATA SET is a series of observations collected by the same methodology. Data sets may be broken into subsets (data files) that are discrete in space and time, in that order. For example, a study was made to evaluate changes in population after disturbance and during succession at the Luquillo Experimental Forest (LEF). Measurements were taken in the grids at El Verde and Bisley. Circular plot censuses were used to measure relative numbers of birds over time and between sites. In a period of ten minutes, all birds heard or seen were recorded on a data sheet in one of two categories: (1) within 25m of the observer or (2) further than 25 m of the observer. Furthermore, censuses were made in the Silver plots following the same methodology but repeated four times before manipulation. In his report, the investigator separated the data into six data files: (1) grid data for birds observed within 25 m of the observer, (2) grid data for birds observed further than 25 m from the observer, (3) all grid data (regardless of the distance), (4) Silver plot data for birds observed within 25 m of the observer, (5) Silver plot data for birds observed further than 25 m from the observer and (6) all Silver plot data (regardless of thec distance). The investigator entered the data in the computer and divided the six data files into two subdirectories containing three files⁽¹⁾ each one (LT25, GT25 and ALL). Observe that the logical subdivision in subdirectories is perfectly acceptable as long as the definition of a data file remains and a proper explanation is given in the documentation form.

Data File Documentation Form⁽²⁾

Each data file with a unique set of variables should be documented. In this form the investigator provides information about the format and types of the measurements (variables) performed in the investigation (i.e. the data file structure)

Documentation Forms for Data Variables⁽²⁾

A variable defines a collection of data points representing measurements or observation taken in the same way and represented in the same format. Examples of variables include elevation, number of birds, snout-vent length, sex, time of day, weather conditions, etc. Variables are therefore measured or determined empirically rather than being assigned an arbitrary value (e.g. plot number, tree number). This form is used to describe in detail each variable within a data set. The form provides information on the kind of variable, units of measurements, and a list of the data files which contain the variable, among other parameters. All measurements taken among all the data files should be documented.

NOTES:

⁽¹⁾ If the investigator has no access to the Internet they can request paper copies of the required form from Data Management. If requested, Data Management will send the form and the guidelines by regular or electronic mail to the Investigator.

⁽²⁾ See the online Guidelines for a detail explanation on how to fill out the forms. If you have any question about completing any of the forms please contact Eda C. Meléndez (787) 764-0000, extension 4943 or e-mail address emelendez@lternet.edu.

Rev. 29 September 2005