This guide explains how to evaluate potential plagiarism using Similarity Reports. It emphasizes that plagiarism cannot be determined by the similarity score alone and multiple factors should be considered.
In this guide:
- How to tell when plagiarism has occurred?
- Similarity vs. plagiarism
- What influences the similarity score?
- Using Turnitin’s tools to produce a more accurate similarity score
How to tell when plagiarism has occurred?
Determining whether plagiarism has occurred requires a careful assessment of both the context and the author's intent. Anyone who evaluates written work must consider factors such as:
- Whether the work aligns with the writer’s previous work and/or skill level
- How well the sources were integrated into the submission
- Whether citations abide with the required formats
- The writer’s understanding of, and adherence to, writing integrity
Similarity vs. plagiarism
The relationship between a similarity score and plagiarism is often misunderstood. Many assume that a high similarity score automatically signifies plagiarism, but that is not always the case. The Similarity Report is a valuable tool for educators, but its primary function is to highlight matching content from other sources. The percentage shown in the report reflects how much a document matches other content in Turnitin’s databases, or to other specific documents (Doc-to-doc). This could include sources from the internet, academic publications, and other written works. Determining whether plagiarism has occurred requires more than looking at the score.
Interpreting a similarity score correctly requires an understanding of the context in which the author's work was produced. For instance, a high similarity score may result from improperly cited quotes or references. On the other hand, a low score does not guarantee the absence of plagiarism. Anyone evaluating a report should consider the broader context surrounding the author's work to make informed judgments about writing integrity.
What influences the similarity score?
Several factors can influence the percentage displayed in a Similarity Report, including (but not limited to):
- Longer documents tend to have higher similarity scores due to the larger volume of text.
- The nature of some documents (like research papers or literature reviews with high levels of quotes and citations) will naturally yield higher scores.
- Users should become familiar with organizational standards for using exclusions and filters to yield a similarity score and report tailored to integrity concerns.
Genre and task expectation also have an impact of whether text similarity is expected in a submission.
| Similarity expected | ||
|---|---|---|
| Genre | Research writing | Yes |
| Argumentative / Analytical / Informative, etc. | Yes | |
| Narrative / Creative writing | No | |
| Reflective writing | No | |
| Task expectations | Research included | Yes |
| Reference to provided source material | Yes | |
| Balance of evidence and original ideas | Yes | |
| Creative or reflective writing | No |
Using Turnitin’s tools to produce a more accurate similarity score
Some aspects of a submission can contribute to an inflated plagiarism score. Turnitin offers some helpful features to detect these aspects and prevent them from influencing the similarity score in an inaccurate way. The following guide will help users understand how to manage exclusions and filters in the Similarity Report:
Additional resources: