That is helpful. Thank you. On Tue, Nov 6, 2012 at 12:31 PM, Jim Clark <[email protected]> wrote:
> Hi > > I think it is the failure to turn over the 7 that most clearly > demonstrates the confirmation bias. Participants are NOT checking an > outcome that would render the premise false, namely finding a vowel on > the other side of the 7. > > Their actual choices are a little more complex to interpret, I think. > Turning over the E could be done to confirm (find even) or to disconfirm > (find odd) the premise. Impossible to know without more information. > > And turning over the 4 could be evidence of confirmation bias (i.e., > checking for the presence of a positive exemplar of the rule). But > turning over the 4 would actually be relevant if the premise was > interpreted as IF AND ONLY IF, rather than IF. Misinterpreting IF as IF > AND ONLY IF leads to some fallacious reasoning, and could be operating > here. > > So, I would probably focus on the not choosing 7 as evidence for the > confirmation bias (which might better be called a failure to reject > bias?). > > Take care > Jim > > > James M. Clark > Professor & Chair of Psychology > [email protected] > Room 4L41A > 204-786-9757 > 204-774-4134 Fax > Dept of Psychology, U of Winnipeg > 515 Portage Ave, Winnipeg, MB > R3B 0R4 CANADA > > > >>> Julie Osland <[email protected]> 06-Nov-12 10:41 AM >>> > Dear tipsters > > > > I need help with the confirmation bias and how the responses of the > majority of students faced with the original Wason Card Selection Task > illustrate that bias. > > > > The example in the book is: > > Suppose that each of the cards below has a number on one side and a > letter > on the other, and someone tells you: *If a card has a vowel on one > side, > then it has an even number on the other side.* Which one(s) of the > cards > would you need to turn over to decide whether the person is lying? E K > 4 > 7 > > To be clear, I totally understand what the confirmation bias is > [tendency > to search for and interpret information in ways that supports one*s > existing beliefs or expectations] and what the correct answer to the > Wason > Card Task is, and why [E and 7*modus ponens and modus tollens, > respectively]. > > According to secondary sources [a gen psych and a social psych text], > Wason > and Johnson-Laird (1972) found the two most comment responses to be > turning > over both cards E and 4, and turning over just card E. These secondary > sources say that these responses [E and 4, and just E] illustrate the > confirmation bias without explaining how these responses illustrate > the > bias. Turning over the card E could result in finding a 4 *an > outcome that > would confirm the rule, but it could result in finding a 7 if the rule > is > false. Because this option could potentially confirm or disconfirm > the > rule I don*t see this choice as a definite confirmation strategy. I > can > see how choosing 4 would potentially confirm the rule, even though > affirming the consequent is not a valid argument. Turning over the 4 > and > finding an E would confirm the hypothesis. Am I missing something > obvious > regarding as two how both the E only and E and 4 combination are a > clear > example of the confirmation bias? Please help. > > > > > -- > Dr. Julie A. Osland, M.A., Ph.D. > Assistant Professor of Psychology > Wheeling Jesuit University > 316 Washington Avenue > Wheeling, WV 26003 > > Office: (304) 243-2329 > e-mail: [email protected] > > --- > You are currently subscribed to tips as: [email protected]. > To unsubscribe click here: > > http://fsulist.frostburg.edu/u?id=13251.645f86b5cec4da0a56ffea7a891720c9&n=T&l=tips&o=21533 > > or send a blank email to > leave-21533-13251.645f86b5cec4da0a56ffea7a89172...@fsulist.frostburg.edu > > --- > You are currently subscribed to tips as: [email protected]. > To unsubscribe click here: > http://fsulist.frostburg.edu/u?id=13433.c7876d6b0f9d5461fd3e87c0d1e51e12&n=T&l=tips&o=21536 > or send a blank email to > leave-21536-13433.c7876d6b0f9d5461fd3e87c0d1e51...@fsulist.frostburg.edu -- Dr. Julie A. Osland, M.A., Ph.D. Assistant Professor of Psychology Wheeling Jesuit University 316 Washington Avenue Wheeling, WV 26003 Office: (304) 243-2329 e-mail: [email protected] --- You are currently subscribed to tips as: [email protected]. To unsubscribe click here: http://fsulist.frostburg.edu/u?id=13090.68da6e6e5325aa33287ff385b70df5d5&n=T&l=tips&o=21605 or send a blank email to leave-21605-13090.68da6e6e5325aa33287ff385b70df...@fsulist.frostburg.edu
