You need more than one number to calculate a standard deviation, so 9 does not have a standard deviation.
Sure it can. But in the survey business, the trick is to select your sample carefully so that they'll be equal, i.e. a sample that is accurately representative of the population.
Absolutely. In fact I would commonly expect it to be. If, for example, the sample mean for the length of a bolt was 5.5 cm, you would certainly hope the standard deviation was a lot less than 5.5 cm. or it would imply bolts with a negative length (not quite sure how you'd do that without breaching some alternate dimension - no pun intended.)
Standard deviation in statistics refers to how much deviation there is from the average or mean value. Sample deviation refers to the data that was collected from a smaller pool than the population.
In the same way that you calculate mean and median that are greater than the standard deviation!
In general, a mean can be greater or less than the standard deviation.
Yes. If the variance is less than 1, the standard deviation will be greater that the variance. For example, if the variance is 0.5, the standard deviation is sqrt(0.5) or 0.707.
When you don't have the population standard deviation, but do have the sample standard deviation. The Z score will be better to do as long as it is possible to do it.
A negative Z-Score corresponds to a negative standard deviation, i.e. an observation that is less than the mean, when the standard deviation is normalized so that the standard deviation is zero when the mean is zero.
Standard deviation can be greater than the mean.
There is no reason for that to happen.
Yes. Standard deviation depends entirely upon the distribution; it is a measure of how spread out it is (ie how far from the mean "on average" the data is): the larger it is the more spread out it is, the smaller the less spread out. If every data point was the mean, the standard deviation would be zero!
You need more than one number to calculate a standard deviation, so 9 does not have a standard deviation.
Yes, it can have any non-negative value.
It does not indicate anything if the mean is greater than the standard deviation.
Anand Mehta said yes and this is correct. You will get a SD, for example, if all of the data points are less than one, or if the data points are very close together and there is not much spread in the data..
Sure it can. But in the survey business, the trick is to select your sample carefully so that they'll be equal, i.e. a sample that is accurately representative of the population.