vemi007
Forum Senior
Topics: 36
Posts: 74
|
The table shows survival information for patients who had operation for a particular form of cancer.
Interval Patients at the Patients who died patients surviving
beginning of the interval during the interval this interval (%)
0-1 year 500 100 80
1-2 year 400 50 87.5
2-3 year 350 35 90
3-4 year 315 31 90
based on this information if a patient survives for one year, which of the following is the probability that he or she will survive for 4 years
a) 0.875 - 0.8 * 0.9
b) 0.8*0.875*0.9*0.9
c) 0.875*0.9
d) 0.875*0.9*0.9
e) 0.9
f) 0.9 - 0.875
|
| vemi007
Forum Senior
Topics: 36
Posts: 74
|
let me redraw the table again...
|
| vemi007
Forum Senior
Topics: 36
Posts: 74
|
please view the attched image for table information.
Attached Files:
untitled.bmp (1292 KB, 67 downloads)
|
| cyra
Moderator
Topics: 29
Posts: 844
|
This one had me stumped too.... when i took the test i chose d thinking that we already know that he has survived for one year...but now i think it shoudl be b as they want to know the probability for all four years...what do you think?
|
| robin082006
Forum Hero
Topics: 471
Posts: 5,125
|
I go with B too.
This is a cumulative frequency. Patents who survive over 4 years are those who have to survive 0-1 year, 1-2 year, 2-3 years, and 3-4 years. so we multipy the frequency of each interval.
___________________
The Key to Succeed is Patience.
|
| docarchana
Forum Guru
Topics: 70
Posts: 515
|
i think its D..
|
| klimt
Forum Guru
Topics: 27
Posts: 605
|
I agree with robin, subjects have to 'pass' each year to finally make it to the 4th...so probability decreases every year
___________________
Traveler, there are no roads. Roads are made by walking.
|
| allie
Forum Newbie
Topics: 0
Posts: 8
|
i go with robbin its B...
to survive by d end of 4th yr u have to survive each year n so probability will be multiplied..
|
| suravi
Forum Newbie
Topics: 5
Posts: 19
|
I think its D. Becos the probablity of surviving each year is independent. If he has already survived oneyear, we can calculate the prob for only the remaining years.
|
| young_doc
Forum Guru
Topics: 55
Posts: 732
|
Agree with Suravi.
Robin would be right if we didn't know that he had already survived the 1st year!
Anyone else?
___________________
First Aid is my Bible...
|
| jamdoc
Forum Elite
Topics: 30
Posts: 244
|
i think its D
___________________
Dont worry.Nobody knows 100%
|
| fongch
Forum Elite
Topics: 71
Posts: 316
|
I go with D too. The survivial probability at 1 year is 1 in the question give.
|
|
| |
| | | | | | | | | | | | |
