Original post by Mimi786**
This might sound dumb, but I always get confused on how to check if the standard deviation is within plus or minus 5% of the mean?? What does that even mean?
SD = 1.02541455
Mean = 82.755
5% of mean = 4.13775
Mean + 5% = 86.89275
Mean - 5% = 78.61725
So in this case, is the answer no, the SD does not fall within plus or minus 5% of the mean?? is that a good thing?
SD = 1.02541455
Mean = 82.755
5% of mean = 4.13775
Mean + 5% = 86.89275
Mean - 5% = 78.61725
So in this case, is the answer no, the SD does not fall within plus or minus 5% of the mean?? is that a good thing?
Can't recall coming across this and Googling isn't helping. Can you provide a link/scan of the orignal question and any context you feel relevant.
Original post by ghostwalker
Can't recall coming across this and Googling isn't helping. Can you provide a link/scan of the orignal question and any context you feel relevant.
Sorry, I should have provided more context
I measured a number of tablets, and the question simply asks to state yes/no if the standard deviation falls within ±5% of the mean
I have provided my working out above for this, but I am confused if the answer is yes or no, and how to work this out
I hope that makes more sense
Original post by Mimi786**
Sorry, I should have provided more context
I measured a number of tablets, and the question simply asks to state yes/no if the standard deviation falls within ±5% of the mean
I have provided my working out above for this, but I am confused if the answer is yes or no, and how to work this out
I hope that makes more sense
I measured a number of tablets, and the question simply asks to state yes/no if the standard deviation falls within ±5% of the mean
I have provided my working out above for this, but I am confused if the answer is yes or no, and how to work this out
I hope that makes more sense
Are you assuming a poisson distribution, the variance should be the same as the mean (give or take a bit ...5%?)
Or a normal distribution where 95% of the distribution lies within +/-2 std devs about the mean (5% lies in the tails)?
or ...
Can you generate a histogram (distribution) of your data?
(edited 4 years ago)
Original post by Mimi786**
Sorry, I should have provided more context
I measured a number of tablets, and the question simply asks to state yes/no if the standard deviation falls within ±5% of the mean
I have provided my working out above for this, but I am confused if the answer is yes or no, and how to work this out
I hope that makes more sense
I measured a number of tablets, and the question simply asks to state yes/no if the standard deviation falls within ±5% of the mean
I have provided my working out above for this, but I am confused if the answer is yes or no, and how to work this out
I hope that makes more sense
I'm not sure what they're getting at:
Whether they actually mean the standard deviation is close to the mean, which as you've shown it isn't,
or whether they're interested in one standard deviation either side of the mean all lies within 5% of the mean.
It's lack of understanding on my part on where they're coming from. Sorry, don't think I can help.
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