## Solved – Finding the mean and standard deviation of an unknown distribution from a sample

I am interested in finding the mean and standard deviation of the whole distribution by looking only at a random sample. I don't know anything else about the distribution (for example I don't know if the distribution is normal or not). Is what I'm asking even possible? Best Answer Sure, your best guess of the … Read more

## Solved – Root mean square vs average absolute deviation

Both Root Mean Square and Average absolute deviation seem like the measures of the magnitude of variability (especially when the variates are both +ve and -ve). What are the rules of thumb to choose one of them over the other? Best Answer In theory, this should be determined by how important different sized errors are … Read more

## Solved – Standard deviation visualization for different time series

I want to visualize the following data in the more concise way possible (only 1 figure of possible!) I have the following averaged and std (grey shaded) profiles, which come from 20 different experiments. I can generate different profiles for different values of N = {1,10,100,1000,…} (The first figure is an example for N=100, the … Read more

## Solved – Standard deviation visualization for different time series

I want to visualize the following data in the more concise way possible (only 1 figure of possible!) I have the following averaged and std (grey shaded) profiles, which come from 20 different experiments. I can generate different profiles for different values of N = {1,10,100,1000,…} (The first figure is an example for N=100, the … Read more

## Solved – What percentage of the students scored more than one standard deviation above the mean

I was given a question for an assignment but I don't understand whether or not I have the right answer… The question is this- What percentage of the students scored more than one standard deviation above the mean? I was given a data set of 50 scores of students in a statistics course and calculated … Read more

## Solved – What percentage of the students scored more than one standard deviation above the mean

I was given a question for an assignment but I don't understand whether or not I have the right answer… The question is this- What percentage of the students scored more than one standard deviation above the mean? I was given a data set of 50 scores of students in a statistics course and calculated … Read more

## Solved – Standard deviation of revenue where numbers are only positive

Is there a way for standard deviation to ignore negative numbers? In other words, how can you make it so that 2 or 3 deviations do not extend into negative territory? When looking at a set of only positive numbers, within one or two standard deviations, I end up with negative numbers. It's essentially impossible … Read more

## Solved – Standard deviation of revenue where numbers are only positive

Is there a way for standard deviation to ignore negative numbers? In other words, how can you make it so that 2 or 3 deviations do not extend into negative territory? When looking at a set of only positive numbers, within one or two standard deviations, I end up with negative numbers. It's essentially impossible … Read more

## Solved – Dispersion of points on 2D or 3D

Suppose that we have a set of points on a line. The amount of dispersion can be measured by standard deviation in this case. My question is, is there something similar for higher dimensions? For example, if there are 100 points (\$i, j: 0 le i le 9, 0 le j le 9\$), then we … Read more

## Solved – Dispersion of points on 2D or 3D

Suppose that we have a set of points on a line. The amount of dispersion can be measured by standard deviation in this case. My question is, is there something similar for higher dimensions? For example, if there are 100 points (\$i, j: 0 le i le 9, 0 le j le 9\$), then we … Read more