Pre-Lab #5:  Biases and short-cuts in thinking

 

In chapter 8 your textbook describes how we categorize information and use context to help make sense out of the world quickly and more easily.  The text then goes on to discuss ways in which we solve problems, noting the structure of problems and our own limits in cognitive capacity in order to demonstrate how we may take short-cuts in our thinking or become "stuck" trying to find solutions.  These limits and previous experiences lead to biases in thinking and decision making because we cannot (or will not) handle all of the possible information that's available.  Lastly, the text discusses more emotion-based biases where probabilities of outcomes and effects of outcomes are biased because of the emotions our anticipated outcomes generate.

 

The biases and short-cuts that are alluded to in the text have names.  In this pre-lab, you'll be given several examples of problems and then definitions of several biases and heuristics (mental short-cuts).  Your task will be to match the type of cognitive bias to the problem.  The pre-lab includes this web page and the next.  Print the next page and write your answers in the spaces provided.  Bring that sheet in to lab.

 

Problems:

Try to answer or solve each of the following problems--

1.  Are there more words in the English language that begin with K or have K as their third letter?

a.                   There are more words that begin with K

b.                  There are more words that have K as their third letter

c.                   Both “a” and “b” are about the same (within 5% of each other).

2.  In the textbook, p. 300, there's a description of the "nine dot" problem, where you need to try and connect the dots using no more than 4 straight lines without lifting the pencil from the page, and they offer a solution. --

Note, however, that there are several ways to connect all of these dots using only ONE straight line without lifting the pencil; the textbook only shows one of these.  Can you think of others?

3.  Suppose someone dealt the following four cards to you, each with a letter on one side and a number on the other (you can see only one side of each card):

E J 6 7

Your job is to find out whether the following rule is true: "If a card has a vowel on one side, then it has an even number on the other side."  Which two cards do you need to turn over to find out?

4.  Read through the following two examples and choose what you would do:

You just won a prize on a game show.  The host gives you two choices.  You can either take a sure prize of $85 or you can spin a wheel for an 85% chance to win $100 (but you’d have a 15% chance of winning nothing).  Which choice would you prefer?

a.             The sure prize of $85

b.            The 85% chance of winning $100

c.             Either one would be equally acceptable

 

You just lost a court case.  The judge gives you two choices.  You can either pay a sure fine of $85 or you can spin a wheel for an 85% chance to pay $100 (but you’d have a 15% chance of paying nothing).  Which choice would you prefer?

a.             The sure fine of $85

b.            The 85% chance of paying $100

c.             Either one would be equally acceptable

5.  Assume that all families with exactly six children are surveyed in a city.  In 100 of these families the exact order of births of boys (B) and girls (G) was G-B-G-B-B-G.  What is your guess as to the number of families in which the exact order of birth was each of the following?  Do you expect more than 100, less than 100, or about 100 families in that city would have each of the orders of births listed below?  Give a number estimate for each alternative:

                                                                        1. G-G-B-G-B-B            _____

                                                                        2. B-B-B-B-B-B            _____

                                                                        3. G-B-B-G-B-G            _____

                                                                        4. B-B-B-G-G-G            _____

 Go to solutions and pre-lab questions about the types of biases shown