Terrorism is very hard to properly define or measure. If a racist person attacks two or more "citizens" (why did you restrict this to citizens and exclude other residents???) and wounds them (aka punches them), this should count by your rules.

This sort of thing happens all the time in the US and probably also most European countries.

This rate still seems high to me. Wikipedia lists 7 terrorist attacks since 2000. Only one of these can be characterized as right wing. Two at least are specifically left wing.

The NCTV keeps records of threat terrorist threat levels in the Netherlands: https://english.nctv.nl/topics/terrorist-threat-assessment-netherlands

The rating is currently 3/5, which is average for the period since 2000.

The NCTV lists jihadism as the principal terrorist threat, suggesting that they estimate the odds of an attack coming from the right wing to be less than 50%.

The base rate for a terrorist attack should be 1/3. Conditional on there being an attack, we can take either low historical number of 1/3 or ~1/2 based on an expert assessment. This suggests a probability range of 1/9 - 1/6 (11-17%).

@StephanHeijl to be clearer on this, the historical rate should probably be even lower, because only 1/7 attacks can be clearly assigned as right wing. Hence the probability range is 5-17%.

@StephanHeijl putting my mana where my mouth is ;)

by what standard will you decide if an attack or a felony counts as "terrorist attack" and not just "felony"? i.e. who will have to call it terrorism to resolve the market?

I ask because sometimes police uses the term "terrorism" somewhat liberal, because when they do, they can use additional tools. For example: In the UK there were "181 arrests for terrorism-related activity" within a year: https://www.gov.uk/government/statistics/operation-of-police-powers-under-the-terrorism-act-2000-quarterly-update-to-june-2021/operation-of-police-powers-under-the-terrorism-act-2000-and-subsequent-legislation-arrests-outcomes-and-stop-and-search-great-britain-quarterly-u
I doubt that any of these case would resolve the market as yes if it had happened in the netherlands.

@BjornJurgens Good question. I was thinking of a "you know it when you see it", but I think a better view would be:

• If perpetrators are prosecuted for a "terrorist felony" under Dutch law. I am not going for conviction here as that takes too long to determine. The assumption is that the charge is not imposed lightly, which seems reasonable to me

• If there are no perpetrators to charge (e.g. in case of death during an attack or succesful getaway) the question is whether the incident is labeled as such by the prime minister or King. Again assuming they will not use the term lightly.

Suggestions for more precision are welcome. I'd certainly not label aiding or preparing for a terrorist attack as YES, as these crimes are distinct from a terrorist felony.

@Vincent My suggestion is to not create markets that are rule messes. Simple questions with simple rules are the best.

For a terrorism market, you'd want a single source (not yourself) that has specific rules on what counts as right-wing terrorism - and you'd use them to resolve the market. "Will Agency X say there was a right-wing terrorist attack in the Netherlands in 2023?".

@AaronKreider You mean like Dutch government or prosecutors (as per the above)?

I think there are reasonable bounds to how we use these words .

@Vincent Yes.