When should questions related to the stock market (DJIA, NASDAQ, etc.) close?

I like things as is. Once you have in-play questions, you are going to have people who feel that this is not straight prediction. They are right, to some extent. People who follow the action have much more information to guide their choices than those who don't. But this is potentially true of most questions on hubdub. Many markets shift between creation and suspension, and those who follow the news have a marked advantage over those who bet it and forget it. Even a Sports question about a particular game which suspends before the game starts can be affected by news of injuries to important players.

So, the "purists" do not stand on as solid ground as they may think they do when they criticise in-play as not being pure prediction.

I think that the in-play markets are the most exciting and fun part of Hubdub, and that there is a large community who play the game daily because of these markets. They're here to stay, and the overall game would be diminished if they weren't.

When we come to the issue of when to close these suckers, I personally don't think that pushing back the suspend time really helps all that much, and it does restrain betting activity considerably, or else cause disastrous losses for some players. The reason for tinkering with the suspend time is either given as "making it more about predictions", or "stopping people from making too much money".

If you push the suspend time back and back until you reach Dow open at 9:30am ET, you will progressively reduce activity on these markets, because even a hour before closing it amounts to a guess (or as some call it, a lottery). The fact is, the closing figure of the Dow is in itself not that interesting an issue (except maybe up or down by how many percent). What gives these markets their actual interest is in predicting, in meaningful steps of time, where is the market going from here. If you overly interfere with this, you just make the market too scary to play heavily.

The issue of excess profits being made in the last few minutes before suspension is perhaps a much more pressing issue. But to some degree we may be overestimating the percent profit that can be made at that time. As an option goes up toward 100%, the percent profit becomes really low. Also, the real gains people make in these markets is when they choose a low percent option just before it becomes the most likely (so some high gains are offset by high losses).

The exception to this is the people who put $10,000 bets (repeatedly) on near-sure things at 90%-99%. The max profit per bet here is between $100 and $1000, but a few of them will sum to about $2000 profit on a sure thing. If there's say 5 markets like this, that's $10,000 in profit on sure things in the last few minutes of the market being open. Clearly being already wealthy can easily lead to being wealthier.

But if we want to deal with that, I think there's a much better idea than playing with suspend times. Basically why not have the max bet on in-play markets be reduced to $1000 or even $500? This at least opens up the wagering when a new option becomes the likeliest to more of the people playing.

If, on top of this, we still feel that too much daily profit is being made on financial markets, then I'd suggest taxing the profits on in-play questions. Maybe we siphon off a quarter of the profit at cash-in or settlement time. People get the fun of playing, but we compensate for the imbalance in profit-making that these financial questions have compared to the rest of the site.

Another approach might be to not take any more bets on an option when it reaches 95% unless it subsequently drops below 95%, but that's getting a little too complex.