![[Maple Plot]](images/Heights1.gif)
MATH 134 -- Intensive Calculus For Science 2
March 14 -- Histograms to probability densities
This is our class's height histogram (graph representing
the distribution of heights of the 23 students in class on Monday,
March 13).
The variable h is height (in inches), the vertical axis is the fraction of the class having
that height.
plotting commands
| > | with(plots): |
| > | heighthist:=piecewise(h<=59,0,h<=60,1/23,h<=61,0,h<=62,2/23,h<=63,3/23,h<=64,1/23,h<=65,2/23,h<=66,4/23,h<=67,0,h<68,3/23,h<=69,2/23,h<=70,1/23,h<=71,2/23,h<=72,1/23,h<=76,0,h<=77,1/23,0): |
| > | hplot:=plot(heighthist,h=58..80,filled=true): |
| > | gplot:=plot(heighthist,h=58..80,color=black): |
| > | lplot:=plot({[60,t,t=0..1/23],[61,t,t=0..2/23],[62,t,t=0..3/23],[63,t,t=0..3/23],[64,t,t=0..2/23],[65,t,t=0..4/23],[66,t,t=0..4/23],[68,t,t=0..3/23],[69,t,t=0..2/23],[70,t,t=0..2/23],[71,t,t=0..1/23],[77,t,t=0..1/23]},color=black): |
| > | display({gplot,hplot,lplot}); |
| > |
So for example, by considering areas, from this we can see that
* 4/23 = .174 of the class have heights
* 9/23 = .391 of the class have heights
and
* If a person was selected at random from the class, there would be a
probability of 6/23 = .261 (or 26.1%), that the person had height
and
