Create a Data File

There may be situations where it is preferred to pair attribute data to a shapefile's geographic data prior to importing the file into Vesta. This can be accomplished in QGIS (freeware) or in esri software ArcGIS.

Using QGIS

When using the QGIS main user documentation, if you are not familiar with the software or concept of what a Geographical Information System (GIS) is, view the Gentle Introduction to GIS section.

Then you can to proceed to the QGIS Training Manual for further exercises using QGIS.

This is a shapefile with an example display and data layout, as seen if opened in QGIS:

Screenshot

At minimum, shapefiles contain geographic information. In the example above, the shapefile also contains some attribute data ("Poverty" and "Driv.dist"). These attribute data columns have been linked to the geographic data for Michigan counties using a "FIPS" ID variable.

Using Excel

The following is an excel file with an example layout:

Screenshot

Each column of data is named accordingly. The identifier used here is FIPS, and the date is in years. The other columns are attribute data associated with the identifier.

Note The excel example above cannot be used as a standalone data file in Vesta as it does not contain geographic coordinate information. Such a file would be used in addition to a shapefile or some other data file containing geographic information.

The following is an excel file with an example layout that uses latitude and longitude to describe geographic format. Latitude and longitude ranges are -90 and 90 degrees and -180 and 180 degrees, respectively.

Screenshot

Data File Format Notes

  • Column titles cannot be changed once data files have been imported into Vesta.
  • Excel files cannot have more than one sheet (only one tab at the bottom of the program window) before importing into Vesta.
  • Cells can contain formulas, however any cells containing formulas used to generate data (for example, a calculated standard deviation) is converted to a number or text format once imported. We recommend saving a separate version with all formulas removed (i.e., saved as .csv file) and then using this "dummy" data file when importing it into Vesta.
  • Vesta accepts missing values but for space-time data files a record/row is expected for each object at each time period, even if the data is “missing”. See the Missing Data page for more information.