Homegrown Software Guides Searchers to Lost Autistic Man

Slatten's program, called "Search Tracker," used the laws of probability to guide searchers who found Keith Kennedy late Sunday in a wooded area inaccessible by vehicles. He was about a mile from the Trade Lake Camp in Grantsburg, Minn., from which he vanished June 15.

"It really helped because all the indicators were pointing to the general area where he was eventually found," Burnett County Sheriff Dean Roland said of Search Tracker. "It's like a compass -- you have to trust that compass, you have to trust what this program is telling you. When the mathematical numbers say that's the best place to go, you go."

Improving Old Models

The program breaks a search area into smaller units, analyzes terrain, vegetation cover, what searchers have done and recommends which units need to be searched more.

Slatten began tinkering with the probability detection program after Leanna Warner went missing in Chisholm, Minn., in 2003. His efforts became more focused after he attended training in Virginia several months later.

"The national school really gave me the knowledge I needed to run with it," he said.

The school gave students software used to train searchers.

"There were two things wrong with [that software]," Slatten said. "One, it crashed all the time. And two, it was never designed to run a search; it was designed to train you how to run a search. It tried to outthink you."

And it was missing some important features -- like the forest types found in northeastern Minnesota.

"We did some experiments in 10 different forest types here to see how well you could search them," Slatten said. "I incorporated that into the software as well."

Found Alive

The rescue squad has used Search Tracker for about three years.

"This software has really worked well for us," rescue squad Capt. Tom Crossmon said. "It was instrumental in this case. The program just screamed for us to get in and search the area where Keith was found. So we put canine resources in there, which give us better indications where to search."

Kennedy was conscious and alert when a St. Paul firefighter found him next to a creek bed on swampy ground. Based on evidence of matted grass in the area, it appeared Kennedy had been there for two or three days, Roland said. Searchers had passed by the area at least twice, but visibility was severely hampered by dense growth of tall grass, thistles and briars.

"It sounds like it was a bear penetrating the brush, but someone did and they found him," St. Louis County Undersheriff Dave Phillips said.

"That general area was searched a lot, because that was what the probability was saying," Roland said. "We tried very hard to find him and we were successful."

Looking at Wide Availability

Slatten is happy, but not surprised, that Search Tracker helped find Kennedy.

"It uses search theory principles that have been proven," he said. "History is full of examples where these techniques have been used to find the unfindable."

But like any software, it needs to be used properly.

" If you give it garbage, it will spit garbage out," Slatten said. "It was the people from Polk and Burnett [counties] that gave us the data that allowed that thing to do its job."

Search Tracker has been through several versions as Slatten continues to improve it. He and his wife currently are making it more user-friendly.

"If it ever gets to where I'm comfortable sharing it with the world, I'll put it on the Internet for free," Slatten said. "I don't want to make any money at it -- I would be happy if folks search correctly."