ric sims integrating tok across the diploma curriculum nairobi october 2011

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An introduction to knowledge issues

An anatomy of knowledge issuesRic SimsIntegrating ToK across the Diploma CurriculumNairobi October 2011 TerrorHope (?)Result

Headline?Is the tendency to smoke inherited?If parents are smokers does this increase the likelihood that the children become smokers?

Knowledge issues - observationLanguage: how exactly do we define smoker? Once smoked, always smoked, sometimes smoked, 10 a day, 20 a day, 40 a day, only in the evenings? (this is more properly about concepts). Is it sufficient for the definition that just one parent smoked?How do we extract information from the (messy) real world? Questionnaire? Who do we question (parents or children)? Reliability issues, wording of questionnaire (and so on)Knowledge issues 2 - representationParents/childrensmokersNon-smokerstotalsmokers3070100Non-smokers40360400total70430500

Knowledge issues of manipulationIf parents smoking habits did not make a difference we would expect that the proportion of smokers would be the same in both groups (those with smoking parents and those without)(subtlety here: we assume an hypothesis of no effect and try to disprove it cf. Popper and falsification)This proportion is 70/430 = 16.3%Expected distributionParent/childrensmokersNon-smokerstotalsmokers1684100Non-smokers65335400total81419500Parents/childrensmokersNon-smokerstotalsmokers3070100Non-smokers40360400total70430500Actual distributionModel: Chi squaredGiven some basic technical assumptions about the base population what is the probability that the observed distribution was achieved by chance?First we decide on a significance levelWe calculate:chi2 = sum of (observed expected)**2/expectedIn this case let us choose 5% significance level (i.e. We shall accept results which could be arrived at randomly from a uniform distribution with probability of 5% or less)

Chi squaredChi2 = 21. 3 for our resultsFrom the table our results are highly significantthey are even significant at 0.1%meaning that our observed distribution is highly unlikely to come from aneven distribution randomly:i.e. There is a real effecthere

Knowledge issues: interpretationThe mathematical model tells us that there the results are highly correlated (there is a strong correlation between the smoking behaviour of parents and that of their children)But we need to do further work to establish causationWe would need to posit a mechanism a piece of theory that uses general principles couched in psychological concepts to explain how one set of behaviours could cause the otherModels

Find a knowledge issue prompted by the following:The Federal Trade Commission has said that advertisers and celebrities who endorse their products are liable for any untruthful statements they make regarding the effectiveness of their products this includes statements they make on blogs and on social networking sites such as Twitter, Facebook and Myspace. (Financial Times 6 Oct 2009)