Textbook/Unit 02

Fraud & transaction risk

Identity, account takeover, transaction decisions, scams, and misuse.

Unit 02 / The big picture

Read the context. Choose the action.

Four signal groups—identity, intent, device, and behavior—surround a risk decision diamond. Context and policy feed an action branch with allow, intervene, and stop or review. Authentication can support access evidence but does not establish informed intent; a scam may involve an authenticated customer.

Enlarge to read every label and explore the connections

Fraud control combines evidence about identity, device, intent, and behavior. The decision must limit harm while preserving legitimate activity.

  1. Read each signal as evidence, not as a verdict.

  2. Combine the signals at the decision point.

  3. Compare each intervention with the harm and customer cost.

Inside this unit

5 chapters
Three claims. Three kinds of evidence.
2.1 / 15 min read

Identity, credentials, and synthetic profiles

Separate identity proofing from login security and account behavior.

Read chapter
Protect the whole takeover chain
2.2 / 15 min read

Account takeover and account recovery

Protect high-impact actions across the entire account lifecycle.

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Choose the action with the lowest total harm
2.3 / 15 min read

Transaction risk and decision economics

Use signals, uncertainty, and cost to choose proportionate actions.

Read chapter
A genuine button press can fund a false story
2.4 / 15 min read

Scams, money mules, and social engineering

Recognize deception across both the sender and receiver journeys.

Read chapter
One claim. Several possible explanations.
2.5 / 15 min read

First-party misuse, merchant abuse, and feedback

Distinguish deception from service problems and build reliable labels.

Read chapter