Are you asking about turnout in any one local election or turnout over the whole electoral cycle?
I am wondering if over the long term election by thirds means people get in the habit of voting most years (and so turnout is higher) or if they get tired of it or put off (and so turnout is lower).
Obviously there are lots of confounding factors: - who stands, what is happening at national level, demographics of different areas etc. and in any case only a minority of people bother at all. Even so, it would be interesting to know if there is an observable effect.
Put another way, does the "democratic deficit" depend on which of the two mechanisms are used.
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