Larger universities with less selective admissions policies have higher rates of student plagiarism and apply less severe penalties than their more selective counterparts, new research suggests.
In a survey of 93 UK higher education institutions, a total of 9,229 cases were recorded in one year, and 143 students were expelled, according to a Higher Education Academy and Joint Information Systems Committee study.
Researchers found wide variations both in rates of plagiarism and in the penalties applied, which appeared to be linked to type of institution.
Universities and colleges fell into three main categories when separated by their plagiarism policies by the researchers - Fiona Duggan, former head of advice and guidance for the Jisc Plagiarism Advisory Service, and Peter Tennant, a research assistant at Newcastle University.
Among one group, dominated by large, less selective universities, the rate of plagiarism recorded was twice as great (1.04 per cent) as among the group dominated by smaller, low-income institutions (0.51 per cent).
A group of predominantly large, more selective, research-intensive universities had a rate of 0.66 per cent.
Use of harsher measures - penalties more likely to seriously affect the student's degree outcome - also varied profoundly.
Among the smaller, low-income institutions, tougher "degree-level penalties", including suspension, grade penalties and expulsion, were used to deal with just 1.2 per cent of cases compared with 14 per cent among the less selective universities, and 19.7 per cent among the more selective universities.
In small, low-income institutions, expulsion was very rare - 0.3 per cent, whereas it was 4 per cent at less selective universities and 8 per cent at more selective universities.
The evidence suggests that "the inherent characteristics of an institution are considerably more important in predicting the likelihood of a severe penalty than the nature of the offence", the report says.
Across all institutions there were 2,372 instances where students were required to resubmit an assignment for a reduced or capped mark. A total of 2,192 formal warnings were issued.
The average rate of plagiarism was 0.72 per cent - equivalent to 7.2 cases for every 1,000 students - substantially lower than the 25 per cent of respondents who indicated that they had plagiarised in a 2004 survey by FreshMinds.
Among postgraduate students, the rate was higher than among undergraduate students (1.19 per cent and 0.67 per cent respectively).
The vast majority (92.3 per cent) of cases were first offences, which is "reassuring", say the authors.
"Despite the debate regarding the appropriate treatment of a student plagiarist, the relatively low national proportion of subsequent offences suggests that current policies are moderately successful in educating the student or deterring further infringement," the report says.