AccuTest
The development of grayscale Optical Mark Read (OMR) technology was developed specifically to read bubble marks on student test forms using “image density” recognition. AccuTest expands on the functionality provided with the AccuScore OMR engine, resulting in a comprehensive and robust solution for high stakes test scoring in an OMR environment.
OMR is a technology that has been used for data collection in a number of different application areas besides test scoring; surveys, voting ballots and warranty cards to name just a few. Where OMR is used to collect data for statistical purposes, i.e., surveys and warranty cards, conventional bi-tonal (Black and White) images provide adequate fidelity to accomplish these applications. In applications such as voting and test scoring, conventional bi-tonal images do not possess the necessary fidelity, and gray scale or color imaging is required.
Based on the luminance level of the mark, the application determines how to record the mark. Because erasures and other extraneous marks can and do occur on these critical documents, gray scale and color images enable the application to differentiate between a valid mark attempt, an erasure, an errant mark or an attempt to mark two or more responses to a single request. The ability to read gray scale and color images is critical to test scoring accuracy. Scan-Optics’ AccuTest can accurately sense the density of a mark up to 16 darkness levels.
Features include:
- Greater flexibility at low cost
- Ability to scan using inexpensive color or grayscale scanners
- Positive page identification using skunk codes, OCR, OCR/ICR and barcodes recognition
- Ease of use with standard Microsoft-based environment
- Scalable to meet volume requirements
- Built to work with industry standard scanners
- Configurable, secure and built on industry standards
- AccuScore image-based OMR engine
- OMR Edit/Repair
- Accuracy
- Forms definition tools
- Image distortion correction
Conventional OMR forms are developed using a “grid” concept. Typically, “timing marks”, the thick black bars on the edge of the form, are used to identify row(s) of the grid that the OMR uses for reference. The columns of the grid are evenly spaced, starting at a fixed distance from the timing marks. This concept was developed to accommodate OMR scanners that used sensors vs. images for recognition. Using forms in this construct typically requires precision printing to hold the vertical and horizontal dimensions. This also means a higher cost for the forms.
Scan-Optics’ AccuTest provides an alternative to these rigid printing rules. Timing marks are removed and 3 or 4 “reference marks” are added to the form. Reference marks placed at the corners of the document are used to determine the coordinate of a mark target. Reference marks allow greater freedom in the forms design and recognition process -- no longer are marks required to be placed on the “grid”. Now they can be placed anywhere on the form. This eliminates the dependency on the black timing marks found on the edge of typical OMR documents processed on conventional hardware, which in turn eliminates restrictions and/or limitations on the design of OMR documents.
Some examples of documents which cannot be processed with traditional OMR readers, but which can easily be handled by AccuTest are: non-precision printed forms, obstructions covering timing tracks (i.e. students drawing on timing tracks, seals, etc.), and OCR for page identification. Publishers are moving to non-precision printed forms to gain greater freedom and value in their assessment publishing.
