What is the difference between subjective and objective risk?

I originally answered this question on Quora here.
In some ways, all risks can be considered subjective for two reasons.
Firstly, how we perceive risks is a very personal matter based on in-built biases, the experiences we have had and our current situation.

An example from a well-known risk textbook is an icy sidewalk. A child might see that as a fun thing to slide on so their perception is that there is no risk. A retiree will perceive this as a high risk as their chance of falling and becoming injured is higher and more debilitating. If a kid falls, they usually just get up and carry on with what they are doing.

Here, the perception of the same situation is very subjective.
Secondly, how a similar situation affect an individual or group depends on their particular circumstances.

Let’s imagine I’m one of two people big wall climbing somewhere. The threat (falling / gravity) is constant. The impact (literally) would be the same but the risk* we face could be very different.
Why?
Well, I’m not a great climber so my vulnerability to a fall is pretty high. If the other climber is someone like Alex Honnold or Beth Rodden (both world class climbers), their vulnerability to a fall is significantly less. So my overall risk is very high whereas theirs will be fairly low.

*I’m defining a risk as a combination of a threat, vulnerability to that threat and the impact of that threat. So risk = threat * vulnerability * impact. Read more here.

This is a less-rigid use of ‘subjective’ but the point is that the risk posed by a similar situation is still influenced heavily by personal factors.

Read a longer piece on risk perception here

Objectivity is therefore hard to achieve because of this subjectivity and because many of the biases and influences we experience are subconscious and linked to System 1 (instinctive, fast) thinking. However, it is because of these biases that we need objective measures to help us begin risk discussions from a relatively neutral point.

Data is a big help here (assuming we have eliminated as much bias from the data collection as possible).

So if we can gather enough data to give us a good understanding of what the threat looks like (say, the frequency and magnitude of earthquakes in a particular area), we can then start to assess the vulnerability and impact and therefore the risk of this kind of event more objectively.

In this example, anyone who has experienced an earthquake will have a different (subjective) perception of the risk from someone who hasn’t but at least they could begin their discussion from a neutral (objective) position using a data-driven threat assessment. (Trying to establish this neutral start point was a big reason I built the DCDR risk assessment tool.)

So to answer the original question, risks themselves aren’t objective or subjective. It’s how we approach things that makes risks subjective or objective.

Originally published at dcdr.io on October 11, 2018.