No. Mean absolute deviation is usually greater than 0. It is 0 only if all the values are exactly the same - in which case there is no point in calculating a deviation! The average deviation is always (by definition) = 0
If I have understood the question correctly, despite your challenging spelling, the standard deviation is the square root of the average of the squared deviations while the mean absolute deviation is the average of the deviation. One consequence of this difference is that a large deviation affects the standard deviation more than it affects the mean absolute deviation.
No. The standard deviation is not exactly a value but rather how far a score deviates from the mean.
No, a standard deviation or variance does not have a negative sign. The reason for this is that the deviations from the mean are squared in the formula. Deviations are squared to get rid of signs. In Absolute mean deviation, sum of the deviations is taken ignoring the signs, but there is no justification for doing so. (deviations are not squared here)
No, you have it backwards, the standard deviation is the square root of the variance, so the variance is the standard deviation squared. Usually you find the variance first, as it is the average sum of squares of the distribution, and then find the standard deviation by squaring it.
Standard deviation can never be negative.
A negative deviation means that the observation is smaller than whatever it is that the deviation is being measured from.
The mean average deviation is the same as the mean deviation (or the average deviation) and they are, by definition, 0.
No. Neither the standard deviation nor the variance can ever be negative.
Because the average deviation will always be zero.
The mean would be negative, but standard deviation is always positive.
The average deviation is always 0.
No. The average of the deviations, or mean deviation, will always be zero. The standard deviation is the average squared deviation which is usually non-zero.
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.
to find percent deviation you divide the average deviation into the mean then multiply by 100% . to get the average deviation you must subtract the mean from a measured value.
You don't need to. Average deviation (about the mean) is always zero!
No. Standard deviation is the square root of a non-negative number (the variance) and as such has to be at least zero. Please see the related links for a definition of standard deviation and some examples.