The Boating Risk Analysis INnformation System (BRAINS) uses the statistical relationships between accident report variables within the U.S. Coast Guard's Boating Accident Report Database (BARD) System to determine the probability that a specific accident could occur given the conditions entered by a user. BRAINS enables those interested in boating accidents to determine the effect a specific variable, or group of variables, have on the probability that a specific accident could occur based on the relationships between variables within the BARD System.
 

 

1. What do the default values (the variable values already chosen by BRAINS) mean?

2. What does BRAINS actually predict?

3. Why can't I make comparisons across regions?


If you have other questions about BRAINS, you might also want to read about BRAINS or read the using BRAINS section.


1. What do the default values (the variable values already chosen by BRAINS) mean?

Each default value represents either the most common occurrence for variables that allow you to choose an option, (e.g., boat type); or the average value for variables that allow you to insert a number (e.g., wind speed, boat length) for that specific variable independent of any other variable values.

For example, assume that in your accident model the default boat type is Personal Watercraft (PWC), and the default boat length is 30 feet. This means that PWC is the most common type of boat involved in this type of accident and that the average length of all boats involved in this type of accident is 30 feet.

Importantly, the default values here do not mean that the average or most common boat involved in this accident type is a 30-foot PWC.


2. What does BRAINS actually predict?

The BRAINS system uses the statistical relationships between accident report variables within the U.S. Coast Guard's Boating Accident Report Database (BARD). These relationships allow the BRAINS user to determine the probability that a specific accident could occur given the conditions that are entered by the user. BRAINS enables the user to isolate the effect of changes in a specific variable on the likelihood of a specific type of accident occurring.

In addition to allowing the user to predict the likelihood of an accident occurring under common conditions, the flexibility of BRAINS allows the user to predict the likelihood of an accident under uncommon or hypothetical conditions.

For example, the average length of a Personal Watercraft (PWC) in BARD is approximately nine feet. By inserting this combination of values, BRAINS will provide the user with the likelihood of a specific type of accident occurring under those typical conditions.

However, what if the PWC where longer, let's say 15 feet? BRAINS gives you the flexibility to construct this hypothetical scenario and predict the change in accident probabilities due to an increase in the length of PWC. Although this flexibility has the potential to increases the power and usefulness of the system, the user needs to understand that the accuracy of any prediction becomes less reliable as the variable values become less realistic.

NOTE: For a specific example about how BRAINS work, a simple case study is presented in About BRAINS.


3. Why can't I make comparisons across regions?

It is difficult to make direct comparisons across regions when using any of the models because appropriate accident variables may differ across regions.

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