What is the problem with using WEIRD samples?

By Keenal Majithia

What Does WEIRD Mean?

Psychology experiments help us better understand the world around us. One particularly poignant and timely example given the Black Lives Matter movement, is the Stanford Prison experiment in which  men were assigned one of two roles - prison guard or prison officer – and ended up acting in accordance with each role but to an extreme level involving police brutality and revolts. But most psychology experiments are ineffective because they only use participants who are WEIRD: western, educated, and from industrialized, rich, and democratic countries.

Much research needing voluntary human participants, especially in behavioural, emotional or cognitive psychology experiments take place predominantly in such countries and swathes of participants are recruited on university campuses as there is a huge population ready to volunteer for that 30 minute cognitive task for a fiver. It can be efficient recruiting participants this way, but it also means that participant groups are largely more homogenous than we intend them to be.

Experimental Prejudice

This means huge amounts of the global population who have not ever entered higher education, that live in an agricultural nation, are working class, live in countries with different political systems or even living in anywhere that is not the ‘western world’ are not being considered or reflected in research.

I took part in many experiments at university and I fall under almost all of the WEIRD boxes, because I live in the UK which is a developed, democratic nation, was in higher education and I have been brought up, in part, in a westernised way. Participation sheets littered notice boards with the promise of class credits or a tenner. I saw no  efforts being used to recruit anybody from different walks of life or even older people from the town centre because all of the participants they needed were on the researcher’s doorstep at  the university campus.

Ecological Invalidity

Machery found that between 2003 and 2007, 96 per cent of psychological samples came from countries with only 12 percent of the world's populations. The study also found the non-WEIRD counterparts showed major differences across a spectrum of key areas, including visual perception, fairness, spatial and moral reasoning, memory and conformity. 

This is an enormous amount of the population that needs to be explored far more and means previous research cannot be as ecologically valid, as it may only be reflective of certain, relatively small, populations. These vast demographic differences can have far reaching consequences as clinical disorders may manifest differently, behaviours could mean different things and missteps can  be easily made.

Are We Really All So Different?

Many people may assume that we are all human and therefore our basic brain function is pretty similar. At a purely physiological level, we should be able to logically assume that our basic cognitive functions such as planning, perception and processing should be similar enough for us to not need to use cross cultural participants. Surprisingly, this is not the case as Segall et al found that even basic visual processing is not strictly the same universally when comparing findings from the USA and 14 non western countries. The Müller-Lyer illusion (pictured below) had great cultural variation, with the undergraduate group from the USA being on the extreme end and believing the lines to be a different length at a greater rate than non-western participants.

The Mueller-Lyer effect: http://4.bp.blogspot.com/-AVvNVfXGfOc/VOoTdC7YbeI/AAAAAAAAApA/3Bel8I850T0/s1600/Muller_Lyer_illusion.png

If something as low level as this has cultural variation and is said to potentially be influenced by the geometric patterns we see in our environment every day, imagine the differences between groups when it comes to how a mental health disorder may manifest, or how we may process emotional or social stimuli. These lower-level cognitive functions shape how we express and experience things differently. An example of this is the experience of depression in South Asian people. Fenton and Sadiq (1996) found that depression was expressed as ‘weakness, listlessness, tearfulness, sleeplessness, and loss of self-confidence and life meaning’, rather than in terms of low mood or depression as you might traditionally expect in a more western context.

Derasari also found differences in symptomology, as people with depression in India were found to be more likely to have psychosomatic symptoms such as headaches, in comparison to their counterparts in the USA. This wouldn’t have even been known about if mental health research focused exclusively on WEIRD participants. We can only unearth these potentially significant differences and provide  more tailored treatments if research is being done across a more representative sample.

Making It Less WEIRD And More Representative

There are ways to reduce WEIRDness in psychology and to reduce the WEIRDness of the many researchers that are more typically from similar backgrounds themselves.  White people from wealthy, educated and privileged backgrounds can no longer be both the default participant and researcher.  If partnerships are formed with less WEIRD institutions, if research can be promoted and funded in more countries, and if non-WEIRD counterparts are actively encouraged to participate in experiments, samples can become more representative.

There have been some attempts to recruit more participants online in a bid to elevate their diversity like the UCL Study Pool, but how often do you really see the chance to take part in these studies? Additionally, by it being computer based, this still pushes out a swathe of people. Nevertheless, this turtle pace change is happening, but it is up to us to make our voice heard and yell from the rooftops; ‘we deserve for our minds to be seen, to be heard and to be represented in research’.