R ile Olasılığın Temelleri
David Robinson
Chief Data Scientist, DataCamp


fair <- rbinom(90000, 20, .5)
sum(fair == 14)
# [1] 3410
dbinom(14, 20, .5) * .9
# [1] 0.03326797
$$\Pr(\text{14 yazı}|\text{Adil})\cdot\Pr(\text{Adil})$$
biased <- rbinom(10000, 20, .75)
sum(biased == 14)
# [1] 1706
dbinom(14, 20, .75) * .1
# [1] 0.01686093
$$\Pr(\text{14 yazı}|\text{Önyargılı})\cdot\Pr(\text{Önyargılı})$$

$$\Pr(\text{Önyargılı}|\text{14 yazı})=\frac{\Pr(\text{14 yazı ve Önyargılı})}{\Pr(\text{14 yazı ve Önyargılı})+\Pr(\text{14 yazı ve Adil})}$$
$$=\frac{\Pr(\text{14 yazı}|\text{Önyargılı})\Pr(\text{Önyargılı})}{\Pr(\text{14 yazı}|\text{Önyargılı})\Pr(\text{Önyargılı}) + \Pr(\text{14 yazı}|\text{Adil})\Pr(\text{Adil})}$$
prob_14_fair <- dbinom(14, 20, .5) * .9
prob_14_biased <- dbinom(14, 20, .75) * .1
prob_14_biased / (prob_14_fair + prob_14_biased)
$$\Pr(A|B)=\frac{\Pr(B|A)\Pr(A)}{\Pr(B|A)\Pr(A) + \Pr(B|\text{değil }A)\Pr(\text{değil }A)}$$
$$A = \text{Önyargılı}$$
$$B = \text{14 yazı}$$
R ile Olasılığın Temelleri