set A (a,b,c,d,e)
set B (a+1, b+1, c+1,d+1,e+1)
两组数据的standard deviation作比较。题目好像说明abcde是consecutive integer。 在这中情况下是不是应该相等呢?如果不是consecutive integer,答案是不是无法判断呢?
谢谢各路高人
Is there any change in the second case?
When i encounter this kind of question, i will try to key in random number.
If abcde are consecutive, say 1-5, the mean of this set of data would be 3 and mean of setB would be 4. As the 'distance' between each datum from the mean remains unchanged, i.e. 3-1=2 vs 4-2=2, SDs of two set are the same
I applied same strategy to the second case with 5 random numbers,{1,37,46,59,77}, giving the mean of 44 and mean of the corresponding set b is 45.
the distance of each data set between mean and each datum is the same, 44-1 vs 45-2, thus, I conclude that the SD are still the same.