Monday, July 27, 2009

Help with STATISTICS, how do I do these problems?

I just started Statistics and I think that I wasn't paying enough attention. Here are the problems I can't figure out:





Many random number generators allow users to specify the range of the random numbers to be produced. Suppose that you specify that the random number Y can take any value between 0 and 2. Then teh density curve of the outcomes has constant height between 0 and 2, and height 0 elsewhere.





(a) is the random variable Y discrete or continuous? Why?





(b) what is the height of the density curbe between 0 and 2? Draw a graph of the density curve,





(c) use your graphy from (b) and the fact that probability is area under the curve to find P(Y%26lt;1).





then the next problem says





find tehse probabilies as areas under the density curve you sketched in problem 48.





(a) P (0.5 %26lt;Y %26lt;1.3)


(b) P (Y%26gt;0.8)





HELP me please, I am really stuck and don't want to bomb my first homework assignment :)





Thanks bunches





Elizabeth

Help with STATISTICS, how do I do these problems?
1.


a) continuous. Discrete means that you can count each value within an interval. However, since Y can take *any* value, Y could potentially take a value with an infinite decimal, this makes it continuous.





b) .5


All probability curves have a total area of 1.


(my attempt to draw the probability curve:)


.5_____________


...|____________|


...0.........1........2





c) (1-0)/2 = .5


You know that the total area of the curve must be 1, and that this curve is of a uniform density, so you can use the fact that this probability curve is a rectangle to find these areas





2.


a) (1.3 - .5)/2 = .4


b) (2 - .8)/2 = .6
Reply:How's this for probability:





Having someone else do your first homework assignment increases the probability of doing poorly on subsequent assignments.


No comments:

Post a Comment