Assume you need to take a sample of the measure of the wing span of all the 600 birds at a local zoo. You number the birds and then use a random number generator to choose 30 birds. What type of sample is this?
A. Stratified
B. Systematic random
C. Simple Random
D. Convenience
E. Cluster
I can't decide if its D or C... Any takers?

Question

Assume you need to take a sample of the measure of the wing span of all the 600 birds at a local zoo. You number the birds and then use a random number generator to choose 30 birds. What type of sample is this?
A. Stratified
B. Systematic random
C. Simple Random
D. Convenience
E. Cluster
I can't decide if its D or C... Any takers?

blurbendy · Answer

I think because you numbered the birds, then chose them at random, that that would categorize it as systematic random. My intuition was go to with Simple Random, until I read this: http://www.differencebetween.com/difference-between-simple-random-sample-and-vs-systematic-random-sample/

anonymous · Answer

hmm... well now i'm even more confused... how systematic was explained to me was take for instance a line of people, and sally wanted to have people take a survey. She would take every 5th person and have them take the survey... that's how I understood systematic, but now im not so sure....

anonymous · Answer

i would of said c. because i think since you are taking it from the total population it isnt convenience.

anonymous · Answer

i think convenience is when you take the sample from a really large group, and some members of this group can not be choosen bc they are not by you to choose from

anonymous · Answer

also i am not even sure that if you were to use convenience that every member of this group has the same probability of being choosen, because all it really has to do with is the fact that some members of the population you are choosing from is by you and you just select from them instead of selecting from the whole group.

anonymous · Answer

I see...

blurbendy · Answer

Your explanation of systematic makes sense, it's just that my thinking is simple random would be choosing any birds at random, i.e. you wouldn't need to number them.  However, because you are numbering them, this implies that there is a systematic operation going on.  You're using a number generator to pick some number, which then maps to some bird.

I could be over-thinking things, but that's how I see it.

anonymous · Answer

alright, I can see where you're coming from... i'll try Simple random and see what happens, it seems the most reanable in my opinion... thank you both :D

blurbendy · Answer

Good luck!

anonymous · Answer

i think it is simple random, not systematic or convenience. Hopefully we are right :-) :-)

anonymous · Answer

Yep, its Simple random... thank you!

blurbendy · Answer

Nice

anonymous · Answer

hey yw anytime :-)