Question

You wonder if experience effects speciality selected. If all the old elves are the ones making the teddy bears, then Santa only needs an early retirement program, and does not need to retrain the older elves. You randomly sample 80 elves and classify them as old or new. You find that 30 elves are old, and 50 are new. In addition, of the 30 old elves, 10 make drums,15 make teddybears, and 5 make toy trains. Among all 80 elves, 25 make drums, 30 make teddy beats, and 25 make toy trains.

-What is the conditional distribution of speciality for older elves? What is the conditional distributionof speciality for new elves?

-Construct the segmented bar graph.

Answer 1

for older elves

we divide by 30(total sample size for older elves)

		p
drums	10	0.33
teddybears	15	0.50
toy trains	5	0.17
	30

for new elves

all	old	new
25	10	15
30	15	15
25	5	20
	30	50

we divide by 50

	p
drums	0.3
teddybears	0.3
toy trains	0.4

For graph

	new	old
drums	0.3	0.333333
teddybears	0.3	0.5
toy trains	0.4	0.166667