Such a small groups are fine for initial investigation, they have enough of a size to be acceptable statistically for most of the performed studies. I don’t think they’d get approval from ethical committee overseeing animal experiments without initial study like this to conduct something on very high groups.

Can you elaborate why do you think that water is improper control?

Thanks for the feedback. This is exactly what I’ve been hearing from friends that had problems with dogs in UK. They usually described this issue as dog having more rights to do whatever it wants than people.

Thanks for feedback. My friend had numerous occasions where he ended up with dog attacking him in parks in urban areas, this is why I’m curious about it. They’re affraid of the dogs in general so situations like this make them anxious for next days. From their experience, dog owners were often behaving like real twats even in clear situations such as being bitten by a free running large dog(s)without close supervision.

Cultural question to Brits as this happened in UK. Do people care if their dog attacks someone or is highly agressive to humans in UK?

By what I’ve heard from my friends, dog owners often put the blame on attacked/harassed passers-by, they don’t feel accountable for their wrongdoings (i.e. not using leash and not paying attention to where their dog is and what is it doing).