On a whim, I looked at some numbers based on event duration. I tweeted some broad conclusions, but figured y'all might be interested, as well:

Lots of 1-, 2-, & 4-hour events. 3 & 5 are well behind, most everything else is a blip. Few events with *.5 durations, or 6+ hours.

Overall:1-hour events see some mix of poor attendance and/or terrible ticket collection.2-hour do ok.4-hour are solid.

Looking at average attendance:4hr see 80%2hr 70%3 & 5hr ~60-65%1hr 50%>5hr erratic & unique, but often below 30%

My conclusions about convention event durations? Go with 2/4 hours, 5 if necessary. Don’t go above that unless your event is amazing.

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Derek Guder
Event Manager
Gen Con LLC

Can you provide more detail on the events that are 6+ hrs?  I ran two events last year (my first as GM), both were 6 hrs.  I had no issue with attendance, my game was one of those on your High Demand list - so I retrospect, does not surprise me.

How many events were there that were 6+ hours?  Of that total, how many were historical or non-historical minis?

Thanks

An early preview: I have a set of event data from May 11, 2015 (leading up to the opening of event registration).  It has 11959 events; 288 of them were 6+ hours long and 54 of those were HMN (5) or NMN (49).  BGM was the most with 75, primarily tournaments.

Sadly I don't have a data set from close to last year's convention, as the download is now gone and I didn't need to download it after getting tickets.  If you'd like to see data from previous years, you can get some older sets from http://gencon.highprogrammer.com/catalogs/.

Thanks for the early look. 

And it's probably worth reminding everyone that these are very broad trends across all Gen Con events. Individuals games are all unique snowflakes and buck these trends one way or another. A really compelling game is going to get players who are willing to commit an entire day to it.

What I posted here aren't rules, per se, so much as some guidelines. Generally, take a moment and think about your event again if you're going go run a tabletop game for longer than 2 hours or an RPG/LARP or a particularly complex tabletop game for more than 4 hours.

Sometimes it totally makes sense and you're event is gonna be great, but many times you would probably do better planning a smaller, shorter event.

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Derek Guder
Event Manager
Gen Con LLC

I am interested in the miniatures games (HMN & NMN) that were of 6+ hr in duration.  I'd like to get a feel for the titles / game systems driving such long events, and if any of them were tourneys.  From that, I would be interested in the attendance of these events - how many tickets were purchased and how players actually attended. 

I was very much on the fence last year about scheduling an event that runs for 6 hrs.  When deciding what events to sign up for, I am very reluctant to consider an event over 4 hrs unless I know the game and really enjoy it.  If it is a game I am not familiar with, I would stay away in fear that the event / game system may not capture my attention, leaving my to wonder what else I might have done with my time.
 

Overall, we've had good results with attendance for our six hour RPG events.  Caveat:  most of these are either long running popular events (Can of Whupass, All-Thrills) and/or run with high demand game systems (Cthulhu, Shadowun, Hero).  

One suggestion I make for GMs is to err on the side of caution if, even after play testing, you're uncertain how long it will take to finish your event. If you're not sure it can be finished in four hours, submit it as a five hour event.  It's better to finish 30-45 minutes early than run late by the same amount.

I'd agree with watchdog for the most part, other than to say that if your adventure or scenario runs a bit long, try first to cut it down to fit into the 4-hour slot you were originally targeting. But if you can't find some element to remove to speed things up, defintiely give yourself that buffer, yeah. You want your convention game to end up a high note - better to wrap up 20 minutes or so early and chat about how fun it was than to rush to not even get to the final encounter and climax.

With regards to miniatures games at 6 hours or more, there were only 68 in 2015, and this is where we get into what I was talking about erratic data. There are few enough events that hugely successful (or not) event can sway things one way or another.

Looking at general trends, though, the games overall averaged 18 out of 36 scheduled players (or 26 average max, if we remove ongoing drop-in/out events, like Iron Arena). Average individual attendance is around 60%.

Events that were both 6+ hours and better than that average 60% attendance seem heavily weighted by Privateer & Fantasy Flight premier tournaments, as well as those from some other groups (like SWM Gamers, Able Kompanie, etc.).

Removing tournaments leaves around 10 events. Aside from a big Battletech game, the remaining games average 12 players (both scheduled and actual), and are a mix of new and old: Battletech, Mordheim, X-Wing, Dust Tactis, Mordheim. Looking at the titles & descriptions (as someone who is passingly familiar with minis but certainly not deeply immersed in them), all but the Mordheim events seem to be special. Either it's a big, chaotic event or it's got a very cool scenario beyond "let's just play a game of minis."

Looking at the lowest performing events (and removing those for which we have no ticket data at all), it's almost entirely tournaments, mostly from specific groups who know who they are :). Aside from that, the most common thread is a bland title or description. Most (not all) of the events basically boil down to "Come play this game. Here's the point value to build your army." Broadly, they have 7 out of 18 scheduled players.

So I'd say that supports the broad assumptions I drew from general data previously. If you're going to 6+ hours, just make sure you consider your evnet carefully. Odds are, just having a simply tournament may not be enough and you'll want to trim down, unless you have a really cool scenario or idea.

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Derek Guder
Event Manager
Gen Con LLC

I think we (19 & One ) had 2 events that were 6 hours long(one with 4 sessions) . A Napoleonic 25mm miniatures game ( I think it drew 6 of 10ppl) and the other was the Mordheim sessions.  Mordheim is run as a mini,round robin style  campaign with warband enhancement and experience building . Each session was 10ppl and I believe averaged 8 attendees.

Derek - Thanks for the additional info and details.  My 6 hrs events, at least for the near future, will most likely be successful given the popularity of the game system and the glitz of the scenario.  Given the trends cited above, within a few years the popularity and/or glitz will fade and attendance will follow for such a long event.  Thanks again!

grtbrt - Just FYI - I elected to join 19 & One for GENCON 2016.  Looking forward to meeting the crew and working within that game group this year. 

Awesome, glad to hear.

And good luck with your event! I hope you have a blast running it :)

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Derek Guder
Event Manager
Gen Con LLC

I think you'd see several more *.5 duration events if start times were allowed on the half hour. To me personally, this would be a huge improvement, as it would provide much more flexibility in creating the schedule and fitting more events in.

For example, I have one game in particular which often plays in about an hour but can sometimes tend to go about 1.5 hours, though never have I seen it go beyond that. Additionally setup time (and explanation for that matter) are very minimal. Thus it would be extremely helpful to be able to schedule these back-to-back (requiring half hour start times) -- which would eliminate down time at the table & add 2 more full events per day.

There are a few other scenarios I've encountered where this would be useful as well. Anyway, something to consider at least.

It would certainly help in some cases, but it complicates placement more than you would think, and in most cases I would rather have that half-hour buffer to allow for events to run late, setup, let players run from one game to another, etc. than to try to pack 100% efficiency out of tables.

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Derek Guder
Event Manager
Gen Con LLC

Interesting data. I mostly aim for 4 hour experiences, but last year the 4E game I ran went over. Fortunately I had a 1 hour break between the games I was running at the same assigned table and all of the players wanted to finish the scenario. They even bought me lunch while I set up for the next game I was running. Very nice group and they went above and beyond expectations. This did teach me a lesson about running 4E though. I have it set for 5 hours this year. I just hope it doesn't scare off potential players.

Just make sure your event description sounds like a bunch of fun and I'm sure you'll do great.

For small or one-off events, a compelling pitch is more important than almost any other variable, I think.

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Derek Guder
Event Manager
Gen Con LLC