CH. 13 CP

Introduction

• Concept of reasoning illustrated with the question about Robert, a randomly selected male, and whether he is more likely a librarian or a farmer.

• Chapter discusses mental processes related to judgment, decision-making, and reasoning.

Inductive Reasoning

Definition

• Inductive reasoning involves drawing general conclusions from specific observations, leading to probable rather than definitive conclusions.

Factors Affecting Strength of Inductive Arguments

• Representativeness of observations: How well the observations represent overall categories (e.g., black crows in specific locations).

• Number of observations: More data supports stronger conclusions (e.g., sun's daily rise).

• Quality of evidence: Empirical evidence strengthens conclusions (e.g., scientific backing).

Everyday Use

• Example: Predicting an instructor's exam format based on previous observations.

• Assumptions based on past experiences guide daily decisions.

Heuristics in Reasoning

Definition

• Heuristics are mental shortcuts for quick decision-making that may not always be accurate.

Two Major Heuristics

1. Availability Heuristic

   • Events easily recalled are judged as more probable.

   • Demonstrated in judgments about causes of death influenced by media coverage.

2. Representativeness Heuristic

   • Decisions based on how much an instance resembles a category.

   • Example: Judging Robert's profession based on librarian characteristics without considering actual statistics.

Errors in Reasoning

• Common errors arise from biases and ignoring key statistical information (e.g., base rates).

• Conjunction Rule: People mistakenly believe specific conditions are more probable than general conditions.

Attitudes and Biases affecting Judgment

Myside Bias

• Evaluation of evidence biased toward one’s pre-existing opinions.

Confirmation Bias

• Tendency to favor evidence that confirms existing beliefs, potentially leading to flawed reasoning (demonstrated through Wason’s tasks).

Deductive Reasoning

Definition

• Deductive reasoning starts with general premises to reach a specific conclusion.

• Illustrates the importance of the structure of arguments rather than their truth.

Categorical Syllogisms

• Involves premises beginning with All, No, or Some.

• Validity pertains to the logical structure, where invalid premises lead to false conclusions.

Conditional Syllogisms

• Arise in forms such as “If...then” and rely on validity assessments by structure.

• Importance of distinguishing between valid and invalid syllogisms.

Decision Making

Overview

• People face countless decisions daily, affected by a host of factors including emotions, context, and how options are presented.

Expected Utility Theory

• Assumes rational decision-making aiming for maximum benefit, but often undermined by biases. People may ignore optimal decisions (e.g., gambling scenarios).

Emotional Influences on Decisions

• Expected Emotions: Predictions about feelings from outcomes can result in risk aversion.

• Incidental Emotions: Unrelated feelings affecting decision-making can skew biases (e.g., weather during college admissions).

Contextual Effects

• Context of decisions significantly influences behavior (e.g., medical decisions based on prior patient cases).

Framing and Presentation Effects

• How choices are framed affects decisions significantly (e.g., organ donation rates affected by opt-in vs. opt-out systems).

Neuroeconomics

Definition

• A field merging psychology, neuroscience, and economics to understand decision-making brain mechanisms.

Research Examples

• Studies show how brain regions like the insula and PFC react during decision-making, indicating emotional responses play a key role in social and individual choices.

Dual Systems Approach

Overview

• Concept of two mental systems:

  • System 1: Fast, intuitive, prone to biases.

  • System 2: Slow, deliberate, analytical.

• Distinctions help explain common errors in judgment and reasoning.

Summary of Systems Function

• System 1 quickens responses but may overlook key logical structures.

• System 2, while slower, enhances reasoning accuracy; awareness enhances the effectiveness of decision-making.

Conclusion

• Understanding heuristics, biases, types of reasoning, and decision-making can lead to improved critical analysis and better outcomes when faced with judgments.