Exam regulator Ofqual today published guidance for teachers when making judgements in awarding GCSE and A-level grades this summer.

The guidance tells teachers to be “aware of unconscious effects on objectivity”, and that their judgements can be affected by “unconscious beliefs”.

It states: “Without always realising it, everyone holds unconscious beliefs about others. These can be based on things like social factors or identities of others...There is a risk that objective judgements can be affected by unconscious beliefs and other types of bias.

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“Centres are urged to reflect on and question whether any of their judgements might be affected by factors not based on evidence of performance, such as unconscious beliefs or types of bias. These factors can affect judgements of student performance and can also affect the perception of particular pieces of evidence.”

GCSEs and A levels 2021: Ofqual’s warning to teachers about bias

Here are the different types of bias that Ofqual warns teachers to look out for:

Confirmation bias

The guidance says schools should be aware of “confirmation bias”; for example, “noticing only evidence about a student that fits with pre-existing views about them”.

Halo effects

The guidance cites: “Halo effects - for example, where a particularly positive impression of a student overly accentuates their actual knowledge, skills and abilities. Or the opposite, where negative impressions or low expectations of a student hides their actual knowledge, skills and abilities.”

Primary effects

Teachers are also warned about “primacy effects”; for example, “giving undue weight to ‘first impressions’ of a student”.

Recency effects

And there is a risk of “recency effects”, Ofqual says: for example, the bias of “giving undue weight to the most recent interaction with a student”.

Selective perceptions

The risk of giving undue weight to a student’s performance on a particular piece of work

Contrast effects

The risk of over-estimating a student’s likely performance, having first considered a large number of students who are all at a much lower standard.

Exception effects

Ofqual warns about under- or over-grading a student’s performance if it is significantly out of line with (above or below) other students in that centre.

Conformity bias

The risk of placing undue weight on the opinions of others where these are not necessarily supported by the evidence

Affinity bias

The risk of having a more favourable impression of a student’s performance because the student or their qualities or attributes are relatable or similar to one’s own qualities or attributes

Ofqual says this is not “an exhaustive list”, but that it is “designed to raise awareness of the main biases that could negatively impact on the quality of centre judgements”.