Matthew's Journal

This post is an analysis of the probability of the chances for obtaining a particular result of a dice roll for the White Wolf role playing game system. If you're already familiar with the system, you can probably skip ahead to the "Read More" link below and look and the graphs I've provided. If you're not well versed in the mechanics of the White Wolf role playing game system, please keep reading.

In the role playing game system developed by White Wolf, the success or failure of characters' actions is determined by the number of successes on a given dice roll. All rolls use ten-sided dice and the total number of dice thrown, or dice pool, is determined by the sum of a character's rank in a primary attribute and a secondary skill. The number of successes is determined by the number of dice rolled with a value equal to or above the target difficult. A typical difficulty is seven and easy actions will have a lower difficulty while more difficult actions will have a higher difficulty. The minimum difficulty is three and the maximum difficulty is ten.

For a simple action, only one success is needed is successfully complete that action. An example of a simple action would be trying to fire a gun and hit a target. This is a straight forward act and is neither exceptionally easy nor exceptionally difficulty. Thus, it would have the standard target difficulty of seven. A character performing this action would have a total dice pool equal to the sum of their ranks in the dexterity attribute and the firearms skill. For example, a character with a dexterity rating of three and a firearms rating of two would have a total dice pool of five allowing them to throw five dice to determine if the succeed or fail at the action. If they were to roll a 2,5,8,4, and 6, they would have acquired one success since only one die, the one showing eight, had a value greater than or equal to the target difficulty of seven. In that case, it would be up to the Storyteller to determine the effect of only a single success. While the character will have hit the target, it may have been only a glancing blow. If the character had rolled 4,7,9,10,7 and gained four successes, the Storyteller may interpret the greater number of successes as a superior result and say that the character hit the target dead center. A roll of 2,5,6,4,3 would net zero successes and represent a miss since none of the dice rolled showed a value greater than or equal to the target difficulty of seven.

In the White Wolf success system there is the “rule of one” and there is also the critical success rule. The “rule of one” states than any die that shows a one cancels out a single success. So, if a character rolled 1,3,7,8,5 with a target difficulty of 7, one of the two successes would be canceled out by the one resulting in only a single net success. On the other side of the coin, so to speak, is the critical success roll. If the character has a specialty – an area of focus chosen for skills that reach rank four or higher – any ten that's rolled and scores a success may be rolled again for a chance at additional successes.

The discussion of the “rule of one” leads us to a discussion of critical failures or botches. White Wolf has had different incarnations of the botch system that we'll split up into what I'll call the old botch rule and the new botch rule. Under the old botch rule, if you rolled more ones than you did successes – i.e. you scored a negative number of net successes – you rolled a critical failure which the Storyteller is encouraged to interpret as creatively as possible. Thus, if our previously mentioned character rolled a 1,3,1,7,4 with a target difficulty of seven, they would botch their action which the Storyteller could interpret as anything from the character's gun jamming to the bullet sailing high over the target to strike the character's grandmother that he didn't see up over a ridge downrange. Under the new botch rule, the character only botches if they roll a one and no successes. For example, if our character rolled a 1,1,4,2,6 with a target difficulty of seven, they would botch under the new botch rule, but the would not botch if they rolled a 1,1,4,2,7 with a target difficulty of seven despite the fact that they rolled more ones that successes. As you can see, the new botch rule is a little more forgiving than the old botch rule.

Now, as just about anyone who has played a game involving dice can tell you, frequency statistics can be wildly skewed by small sample sizes and player perception. To aid players in having a more reasonable idea of what the probability of achieving a certain result is in the White Wolf system, I designed a numerical simulation where a random number generator was used to simulate 1,000,000 dice rolls for every combination of difficulties and dice pool sizes for the full range of difficulties of three through ten and a range of dice pool sizes from one to twenty. The curves in the plots that are to follow show the percentage chance of rolling a selected number or more successes for a given difficulty and a given sized dice pool.

The charts themselves are pretty self explanatory. Simply choose a chart based on whether you're playing under the new botch rules or the old botch rules and by your target difficulty. From there, select the minimum number of successes that you would like and use the number of dice in your dice pool to select the spot on the curve where you can obtain the probability of meeting or exceeding your desired minimum number of successes. For example, if you look at the chart for a difficulty of seven under the new botch rules, you'll see that for a dice pool of five you have about a 75% chance of rolling one or more successes, a roughly 20% chance of rolling zero successes, and approximately a 5% chance of botching the roll. Please click "Read More" to see the charts.

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I'm home and it feels great. However, Jake is just starting his part of VOCALS. He has a blog at dopplerjake.blogspot.com. Read it to follow along what's going on with leg 2 of the VOCALS cruise.

I've checked out of my hotel room.
The VOCALS findings and progress meeting starts at 1:00pm.
I'm giving my 10 minuet talk at 3:00pm.
I'm leaving for the airport at 6:30pm.
My flight leaves for Santiago at 9:00pm.
I travel for a billion years (24 hours).
I finally get to go home.

All times are Chilean (GMT -3).

In case anyone was curious, the water draining in my hotel in Arica, Chile spins clockwise.

Today is my last full day aboard the Ronald Brown. We're scheduled to arrive in Arica around 10:00am local time tomorrow. Already things are winding down on the ship. There are numerous conversations about what people are going to do when the get to Arica. Mostly the discussions center around travel plans, where to get good food, and what bars are within stumbling distance of the hotels. People are starting to pack up their things, stow equipment, and clean up their work areas. While I'm not packing my clothes into my duffel bag just yet, I am working on tidying some things up and getting ready to have Jake take my place. I'm making sure all the data I've collected so far is organized and written to my external hard drives. I'm making sure that I've collected any data from the other scientists that I think will come in handy. I'm making sure that I have a lot of written instructions so that Jake will have a reference for how to do some of the tasks that I've had to figure out on my own.

Overall, things just feel like they're coming to a close. While my part in the VOCALS project is nearing its conclusion, things aren't over yet. There's still one more day of data to collect. On the 5th of November, Guy Fawkes Day, I'll be training Jake on the things I've been doing on ship and on the things I've learned so far. I'm trying to get a speaking spot at the mid-project meeting on the 6th to present an outline of how we're using the Brown's C-band radar, some interesting things we've seen in the data, and where we're putting our data for the world to preview. Speaking of that final point, the NCSU online field catalog can be found at precip.meas.ncsu.edu/vocals. When I go home to Raleigh, VOCALS will still be going strong. While my month long odyssey will come to a close, Jake's will just be beginning. Also, once I'm home, I'll probably take my place in the shore-side support role. While I've been on the Ronald Brown, the rest of the research group back at NCSU has been working hard processing raw data and analyzing the meager amount of data the Brown's limited internet bandwidth allows me to send out.

I'm starting to get excited about the prospect of getting off the ship. The thing I'm looking forward to the most is sleeping in a bed that doesn't move. Anyone with romantic notions of the ocean waves gentle rocking them to sleep has never been woken up by bumping their head into the wall when the boat makes a sudden roll. I've gotten used to sleeping on a pitching and rolling ship, but that by no means suggest that I prefer it to my usual terrestrial sleeping arrangements.

Happy Halloween, everyone! We here on the Ronald Brown are getting into the Halloween spirit. The women among the science party have disappeared and murderous pirates have taken their place. The shrill battle cry of "Arrrgh!" echoed across the mess deck during lunch. The balloon for today's 16 UTC sounding was replaced with the Great Pumpkin who spreads Halloween cheer. To all of you who may be in Raleigh, go enjoy the Haunted Hillsborough Hike for me.

Dan Wolfe and Lelia Hawkins prepare the Great Pumpkin for release

Most of the instruments that are deployed either on an open-ocean buoy or on the mooring line are unable to transmit their data to shore via satellite phone. They have to store their data on internal memory cards. As a result, if you want to collect the data from those instruments you have to recover the buoy and the mooring line, disassemble the instruments, and extract the memory cards. Now, the buoys that you recover have usually spent a year or more in open waters with only birds and aquatic life to keep them company. In fact, many sea critters decide to call the buoy and it's mooring home. After a year at sea, the buoy and mooring line harbor their own ecosystem. Read on to see what I mean.

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One of the tasks in completing the VOCALS mission to study ocean and atmospheric processes and interaction involves maintaining a buoy with myriad instruments in the vicinity of 20S, 85W; right in the heart of the Eastern Pacific stratocumulus region. The buoy we carried with us on the Ronald Brown for deployment is the ninth in a series of buoys deployed to study this region and it is so dubbed Stratus 9. Stratus 9 and it's deployment is mainly handled by the fine folks at Woods Hole Oceanographic Institute including our chief scientist, Bob Weller. Deploying an anchored open-ocean buoy is no small task, especially when the sea floor is 4500 meters (2.8 miles) beneath the waves. However, the Woods Hole crew makes it look easy.

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