Categories of Attribute Data Entry: Manual, Digitizing, and Scanning (Especially for GATE-Geospatial 2022)

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Attribute data is qualitative data that can be counted for recording and analysis. Examples include the presence or absence of a required label, the installation of all required fasteners.

Attribute data is not acceptable for production part submissions unless variable data cannot be obtained.

Categories of Attribute Data Entry

There are two categories of attribute data entry:

This Figure Shows Categories of Attribute Data Entry

Field Definition

Usually includes field name, data width, data type and number of decimal digits.

Width refers to the number of spaces reserved for a field

  • Data width
  • Data type (must match GIS package)
  • Number of decimal places
  • Include space for negative sign and decimal point

Method of Data Entry

There are three types of data entry:

This Diagram Shows Three Types of Data Entry

Manual (Via Typing on Keyboard or Importing Text Files)

Manual data entry can bring into GIS either collected or measured data. These data exist as simple text files or binary files. Text files should have at least two columns with X and Y coordinates. Binary files are usually a product of the software package associated with measuring device.

Digitizing

Digitizing is a process of entering digital codes of analyzed data into computer. Digitizing can be manual (using digitizing tablet) or automatic (using scanner) . The difference between two methods is that digitizing tablet allows to do georeferencing during the digitizing process, while scanning requires georeferencing later, after digital file has been created. Another difference between methods is speed and accuracy of the data processing.

Scanning

Apparent slowness of the work on digitizing tablet compensates often for the amount of editing after scanning process. At the same time good scanning allows automatic layer separation, while digitizing of the map on a tablet requires manual creation of separate themes. In this case the condition of the original hardcopy is very important. Since human operator can use more cognitive tools and knowledge than the software support for scanning device, digitizer can handle better the hardcopy in a poor condition. Special kind of scanned data is remote sensing image, taken either by satellite camera, digital camera or video camera.

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