7/24/2019 Conventional Wisdom, Experience, And Sampling Error

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CONVENTIONAL WISDOM, EXPERIENCE, AND SAMPLING ERROR

What we mean by what we call 'e!e"#ence' #$ act%ally a '$am!l#n&' ( l#(e ) ) w#th 'l#(e'

cn$t#t%t#n& the blen* ( +a whate-e" the w"l* #$ an* +b %" l#te"al #n-l-ement #n an*w#th #t. In th#$ "e$!ect, e-e"y !$$#ble /#n* ( act#n " #nte"act#n #n l#(e +#ncl%*#n&th%&ht$, e-e"y !$$#ble 'e!e"#ence', #$ act%ally an em!#"#cal $am!l#n& ( the ttal#tythat we "e(e" t an* *e$#&nate a$ '"eal#ty'.

It $h%l* be clea" that ) ) w#th n"mat#-e +!e"ha!$ e-en ("actal $t"%ct%"e$ a!!ly#n& atan* ac"$$ e-e"y le-el ( ab$t"act#n " $%b)&"%!#n& ) ) the"e #$ an %ne0%al le-el ($am!l#n&, #.e., a ("e0%ency *#$t"#b%t#n ( $am!l#n&, (" all act#n$ an* e!e"#ence$ (h%man$.

Th#$ #$ m"e than 1%$t $ay#n& that $me th#n&$ ha!!en " a"e *ne m"e (ten than

the"$. M$t #m!"tantly, #t tell$ %$ that the cn(#*ence attach#n& #n a $tat#$t#cal $en$e t!a"t#c%la" e!e"#ence$ #n l#(e ) ) the cn(#*ence that a $am!le acc%"ately "e(lect$ thewhle ) ) $h%l* tem!e" %" cn(#*ence that the e!e"#ence tell$ %$ $meth#n& acc%"ate" !a"t#c%la"ly #n$#&ht(%l ab%t "eal#ty " what the w"l* #$.

In $h"t, nt all e!e"#ence$, an* th%$ nt all cn-ent#nal w#$*m +be#n& ba$e* ne!e"#ence #$ e0%ally "el#able. An* th#$ #$ the #m!"tant !#nt2 cn-ent#nal w#$*m#t$el( ha$ a ("e0%ency *#$t"#b%t#n. Sme ( #t #$ m"e "el#able than the "e$t ( #t.

Th#$ m%ch, ab-e, $h%l* be b-#%$.

Whe"e #t &et$ #nte"e$t#n&, hwe-e", "eally t"%ly #nte"e$t#n&, #$ when y% a!!ly th#$ #n$#&htt the (act$ that +a $!ea/#n& n"mat#-ely, m$t !e!le e!e"#ence ty!#cal e!e"#ence$wh#le (ewe" !e!le e!e"#ence aty!#cal e!e"#ence$ 3 an*, +b the a-a#lab#l#ty ( -a"#%$ty!e$ ( e!e"#ence$ #$ #n $#&n#(#cant !a"t *ete"m#ne* by #ncme, !$#t#n ( a%th"#ty, "*m#nance3 an*, +c e!e"#ence #n ma/#n& the m$t #m!"tant *ec#$#n$ a((ect#n&$c#ety #$ an* alway$ ha$ been l#m#te* t a "athe" $mall cla$$ ( #n*#-#*%al$ +"%le"$,lea*e"$, !%bl#c ((#c#al$.

 All ( wh#ch $h%l* ma/e #t n $%"!"#$e that n the b#&&e$t #$$%e$ an* 0%e$t#n$ (ac#n&%$ ) ) e.&., whethe" we $h%l* & t wa" ) ) the"e #$ a -an#$h#n&ly $mall l#/el#h* thate#the" the !%bl#c +wh ha$ -#"t%ally n e!e"#ence ma/#n& $%ch a *ec#$#n, " !%bl#c((#c#al$ +wh ("m a $am!l#n& !e"$!ect#-e a"e $ (ew #n n%mbe"$ a"e "#&ht #n thecncl%$#n$ they ("m " the *ec#$#n$ they e$!%$e. In bth ca$e$, #n $h"t, thee!e"#ence le-el #$ ab%t an #nch *ee!, an* the cn(#*ence attach#n&, the"e("e!"!"t#nately lw.

I$ #t any wn*e" th#n&$ a"e $c"ewe* %!4