Excerpt: Gods Tomorrow

He threw his hands up, deeply offended, and turned his back on her with a huff. She bit her lip, wishing she'd been more circumspect, but when she said, "I'm sorry," he just hmphed again, and kept his back to her.

Giving up on him, she settled into her seat and pulled out her handheld as the plane began to taxi. She brought up personal details on her new suspect, Martin Door. She glanced over his financials first, and he fell squarely in the well-off-but-not-what-you'd-call-rich category. He seemed to be in the same line of work as Ghoster, contracting for huge sums with the major Aggregators, though he hadn't done a lot of work recently.

Then she checked out his identifying information. Five eleven, born in the previous millennium he was pushing fifty. She had HaRRE generate a model of him, and considered it for some time while vocal samples played in her headset, familiarizing her with his voice. Her first impression was that he didn't wear his age as well as Ghoster did. Heavyset, shown in jeans and a baggy shirt, he didn't strike the same cutting figure. There was something inherently friendly about his face, though, eyes sparkling above rosy cheeks. He looked like the proud owner of a clever secret, and it was quite inviting.

She hated when HaRRE made her suspects seem likable. She trusted the software -- it drew on an amazing, unlimited source of data, and it could make remarkably accurate predictions -- but sometimes she hated it. Still, she knew as well as anyone how friendly criminals could be. Hathor gave her access to a person's whole life, not just the frantic, panicked moments that so often led to bad choices, but the quiet, happy hours at home with the kids, the deeply reverent contrition of a prayer or confession. She hated when HaRRE made her suspects likable, but she knew better than to let it interfere with an investigation.

Still, he looked so kind.

After half an hour of the silent treatment, Karen jumped when Ghoster suddenly spoke right next to her ear. "Same old Martin," he said with a chuckle. "He's looking good."

She glanced at the sleek salesman in the seat next to her, trying to guess if he was being sarcastic, but he seemed earnest. He reached past her and touched some controls on the screen, drawing up Martin's location details. He laughed. "Still in old B. A."

Her earlier train of thought rose up in her mind, and she asked, "How does the system generate a model?"

Ghoster didn't answer right away. He finished reading the information on the screen, then dropped back into HaRRE where Martin stood frozen against a white background."

"It's a weighted composite," he said. "Any time Hathor recognizes someone on a camera -- whether it's a security camera, a Hathor Courtesy Recorder, or just a snapshot on someone's handheld -- if Hathor can associate the image non-redundantly with an ID in the database, that image is stored forever. Over time, Hathor accumulates enough visual data to estimate a model." His voice was lecturing, and she recognized a pride of ownership in it. "The magic number seems to be in the tens of thousands of images for a single model, and hundreds of thousands to get realistic animation. These days, that's generally a couple weeks out in public."

She nodded. "I understand most of that, but facial expressions, personalities--"

"All of that shows up in the photos," he said. "The weighting algorithms differentiate between short- and long-term characteristics, like the difference between height -- which fluctuates rapidly in a person's early years -- and general build, which really doesn't. Long-term characteristics are primary predictives, with more recent short-term characteristics applied for personalization. Basically...long-term characteristics have a constant weight, but short-term characteristics have a rapidly diminishing weight as they age. Between the two, you get a generally recognizable model that's always pretty up to date."

He zoomed in and pointed to Martin's friendly smile. "Ephemerals like facial expressions, clothing preferences or accessories, have extremely short lifespans, so this is probably what Martin most looked like in the last... say...week. Give or take twenty hours."

"I get all that," she said. "What I want to know is, could someone like you manipulate that?"

"The source data for the model? Yes, but it would be a lot of work--"

"I meant the expression, specifically. The personality. Can it be...hacked?"

He barked a laugh. "Well, yes," he said. "If you know what you're doing, you can go in and manipulate either the reference images themselves -- all hundred-thousand-plus-per-week -- or adjust the long-term weighting values and predictives associated with the individual identity. That's how I would do it, if I were doing it. But the old ways still work best. You want to look like an ogre in HaRRE, spend a week tromping around in public, making angry faces and flipping off little babies. It'll show up. You want to come off as happy and kind," he zoomed back out and waved at Martin's avatar, "casual and approachable and oh-so-innocent, all you have to do is spend some time making sure Hathor sees you looking like that. Ephemerals morph in so quickly, it wouldn't take much effort. Fake it 'til you make it, as they used to say."

Karen frowned. "Martin would know that? How to do that?"

Ghoster looked at her for a moment, clearly incredulous. Finally he said, "Yes...yes, I'd say so. You do know who Martin is, don't you?" When she just looked blank, he sighed. "Dear lord, little girl. It's time for a history lesson."