In: Statistics and Probability
This is a standard deviation contest. You must choose four
numbers from the whole numbers 0 to 10, with repeats allowed.
Step 1:
Choose four numbers that have the smallest possible standard
deviation. What is the numerical value of s in this case? Give your
answer as a whole number (meaning no decimal places).
Step 2:
Is there more than one possibility for choosing four numbers that
have the smallest possible standard deviation?
|
|||||||||||||||||||||||
|
1. Standard deviation can be small (that is zero) if all the values in the sample are same. Hence, the 4 values can be
1,1,1,1
2. Yes
Yes, there are more than one possibility for choosing four numbers that have the smallest possible standard deviation. Until, all the 4 numbers are same the standard deviation will not change from 0. So, the 4 values can also be (0,0,0,0) or (2,2,2,2) or (3,3,3,3), etc.
3. Standard deviation will be large when the values are far from each other. In the given possible set 0 and 10 are the values wihch are far from each other than any other values. Hence, the possible 4 vlaues that could have larger standard deviation will be
0,0,10,10
The inputs for lanunchpad would look like
'11','11','10','10'
4. No
Standard deviation will be large when the values are far from each other. Since, there are 4 values, changing the value of one would also lead to smaller standard deviation than from the the 4 values of (0,0,10,10). Therefore, the only possible values are (0,0,10,10). There is no more than one way to choose four numbers that give the largest possible standard deviation.