Lect 12 Reasoning & Decision Making PDF

Lect 12: Reasoning & Decision Making Contents: Reasoning – definition → Deductive Reasoning → Inductive Reasoning Decision Making - definition  What is Reasoning? Two types of Reasoning Cognitive processes by which people s...

Lect 12: Reasoning & Decision Making Contents: Reasoning – definition → Deductive Reasoning → Inductive Reasoning Decision Making - definition  What is Reasoning? Two types of Reasoning Cognitive processes by which people start with information and come to Deductive: a conclusion logically follows conclusions that go beyond original from premises information Inductive: arrive at conclusions that Eg: Using heuristics (mental shortcuts) in are probably true, based on evidence perception or constructing memories  What is Decision Making? Making choices between alternatives Eg. Buying an apartment, buying the perfect ice cream Can involve both deductive and inductive reasoning  Deductive Reasoning S t a r t s w i t h a g e n e ra l s t a t e m e n t o r p r e m i s e. Leads to a specific, logical conclusion. Deductive B a s i c f o r m o f d e d u c t i ve r e a s o n i n g : Sy l l o g i s m s A syllogism consists of: General 1. Tw o P r e m i s e s ( s t a t e m e n t s a s s u m e d t o b e t r u e ). 2. O n e C o n c l u s i o n ( d ra w n f r o m t h e p r e m i s e s ). E x a m p l e o f a Sy l l o g i s m : Premise 1: All cats are mammals. Specific Premise 2: All mammals are animals. Conclusion: Therefore, all cats are animals.  Two Approaches to Study Syllogisms 1. Normative Approach: Focuses on logical reasoning. Identifies which syllogisms are valid based on formal rules of logic. Example: Premise 1: All dogs are animals. Deductive Premise 2: All animals have cells. Conclusion: Therefore, all dogs have cells. Reasoning: Normative reasoning evaluates this as valid because it logically follows. 2. Descriptive Approach: Syllogisms Focuses on how people actually think. Studies how well individuals can evaluate whether a syllogism is valid. Deductive Example: General Premise 1: All birds can fly. Premise 2: Penguins are birds. Conclusion: Therefore, penguins can fly. Descriptive reasoning investigates why people might mistakenly believe this is valid due to Specific incorrect assumptions.  Invalid Syllogism (Normati ve): P r e m i se s : P r e m i se 1 : A l l c a t s a r e m a m m a l s. P r e m i se 2 : A l l d o g s a r e m a m m a l s. Conclusion: Therefore, all cats are dogs. Re a s o n i ng : T h i s s y l l o g i sm i s i n va l i d b e c a u s e t h e c o n c l u s i o n d o e s n o t l o g i c a l ly f o l l o w f r o m t h e p r e mi s e s , e ve n t h o u g h t h e p r e mi s e s are true. Invalid Syllogism (Descripti ve ): P r e m i se s : 1. P r e m i s e 1 : S o m e p e o p l e w h o e x e r c i s e a r e h e a l t hy. 2. P r e m i s e 2 : J o h n e x e r c i s es. 3. C o n c l us i o n : T h e r ef o r e , J o h n i s h e a l t hy. Reasoning: People might wrongly think it's true because of common beliefs (like exercising means being healthy), but the reasons don't logically prove the conclusion. So, it is invalid. Inductive Reasoning: Starts with specific observations or evidence. Leads to a general conclusion that is probably true. Example: Inductive After observing that the sun has risen Specific every day so far, you conclude the sun will rise tomorrow. General Inductive Reasoning Four Types of Heuristics that cause errors in Reasoning: Availability Heuristic Illusory correlations Representative Heuristic Conjunction Rule Confirmation bias Heuristics are mental shortcuts or "rules of thumb" that our brain uses to make decisions or solve problems quickly and efficiently  Availability Heuristic Explanati on : People judge the likelihood of an event based on how easily examples come to mind. If something is easier to recall, we tend to think it's more common or likely to occur. Example: Af ter buying an iPhone, you suddenly feel like ever yone around you has the same phone, but you just notice it more because it's relevant to you now. Af ter hearing about a plane crash on the news, a person might think that f lying is extremely dangerous, even though statistically, car accidents are far more common. Illusory Correlations Explanati on : This occurs when people perceive a relationship between two variables, even when no such relationship exists. Example: Believing that wearing a "lucky shir t" always helps your favorite team win a game, even though there is no actual connection. Believing that Malaysian Badminton team loses ever y time you watch the game, because each time you do, they lose. In reality, the outcom e of the game has nothing to do with whether you're watching or not.  Representative Heuristic Explanati on : Judging the probability of an event based on how similar it is to a prototype or stereotype rather than actual statis tical evidence. Example: Assum ing someone is a librarian because they are quiet, wear glasses, and love books, even though statis tically, there are more people in other professions. Believing a well -dres sed person driving an expensive car must be wealthy, even though they could be in debt.  Confirmation Bias Explanati on : Conf irm ation bias happens when individuals prioritize information that conf irm s their beliefs and dismiss evidence that contradict s them. Example: If you believe a par ticular diet is ef fective, you might focus only on stories of people who lost weight on it, ignoring cases where it didn’ t work or caused health issues. A student thinks they're bad at math and only remembers times they did poorly on tests, ignoring when they solved tough problem s or got good grades. Reasoning & the Brain Prefrontal Cortex (PFC): important in reasoning, problem solving & working memory Summary Inductive vs Deductive Reasoning Deductive: A process where conclusions are logically derived from given premises. Inductive: A process where conclusions are generalized based on specific observations or evidence. Summary 4 types of heuristics that cause errors in inductive reasoning: 1. Availability Heuristic 2. Illusory correlations 3. Representative Heuristic 4. Confirmation bias