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Questions tagged [stdev]

Returns the statistical standard deviation of all values in the specified expression.

STDEV is used when the group of numbers being evaluated are only a partial sampling of the whole population. The denominator for dividing the sum of squared deviations is N-1, where N is the number of observations (a count of items in the data set). Technically, subtracting the 1 is referred to as "non-biased.

https://msdn.microsoft.com/en-us/library/ms190474.aspx

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SQL - STDEVP or STDEV and how to use it?

I have a table: LocationId OriginalValue Mean 1 0.45 3.99 2 0.33 3.99 3 16.74 3.99 4 3.31 3.99 and so forth... How would I work out the Standard Deviation using this table and…
DtotheG
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Getting "NA" when I run a standard deviation

Quick question. I read my csv file into the variable data. It has a column label var, which has numerical values. When I run the command sd(data$var) I get [1] NA instead of my standard deviation. Could you please help me figure out what I am…
evt
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var, sd, cor functions that have n as denominator

var, sd, cor functions in {stats} use n-1 as a denominator (where n the number of observations). Out of curiosity, are there equivalent function that use n as a denominator?
ECII
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Identifying statistical outliers with pandas: groupby and individual columns

I'm trying to understand how to identify statistical outliers which I will be sending to a spreadsheet. I will need to group the rows by the index and then find the stdev for specific columns and anything that exceeds the stdev would be used to…
Thomas
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Find outliers by Standard Deviation from mean, replace with NA in large dataset (6000+ columns)

I've found a few answers similar to what I'm looking for, but the code has not worked. I need to replace all outliers (as defined for our purposes as more than 2 SD away from the mean), of each column with NA or NULL. I'm trying to have this iterate…
norcanich
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Python multiple lists of different lengths, averages and standard deviations

Given the array of lists below, i want to be able to create a new list, giving the average and standard deviation of the columns a = [ [1, 2, 3], [2, 3, 4], [3, 4, 5, 6], [1, 2], [7, 2, 3, 4]] Required result mean = 2.8,…
Hagakure87
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How can I group Standard Deviation of multiple sets

I have a group of respondents (e.g. 4), each answering a few questions (e.g. 10 questions). The questions belong to 3 groups (Basic, Advanced, Other). I want to calculate the Standard deviation for each group (STDev for the Basic questions, STDev…
Tom
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How to sort the images by filename, and then calculate the standard deviation and mean (Python)

I would like to ask if is there any method to sort the filename (ascending order) of the image files first, followed by doing the calculation of the standard deviation and mean of each image file? dir_path = "The file path" listOfImageFiles =…
Neko Lim
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combining STDEV & VLOOKUP

I am trying to find the STDEV of a specific teams score based on the seasons completed games. I want to accomplish this by using vlookup. I came up with this formula but it shoots a DIV/0 error. =STDEV(vlookup(B19,'2021 Game…
TooTallDerr
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What is the difference between statistics.stdev() & numpy.std() and which is more precise?

I used this dataset: lst = [81922.00557103065, 82887.70053475935, 80413.01627033792, 81708.86075949368, 82997.38219895288, 84641.50943396226, 81929.82456140351, 82632.24181360201, 77667.98418972333, 73726.47427854454,…
whocares
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SQL Server STDEV() Function for decimals not matching Excel STDEV() Function

Just wondering anyone knows the formula behind STDEV() (for any version of sql server), or why standard deviation for values such as these decimals are different. My goal is to explain this difference in calculation to our QA department who can…
tetsballer
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How to get the means and standard deviations of two overlapping normal distributions?

I have the following plot: I would like to estimate the means and standard deviations of the apparent overlapping normal distributions. This is slightly complicated by the fact that since the data is based on hour of the day, it also is circular…
Mark Solinski
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Is there a way to visualize a mutliple regression (more than 3 independent variables) +- 1 SD in R?

I am trying to (i) visualise a multiple linear regression (>3 independent variables) and (ii) plot a standard deviation corridor for my linear regression line, but I am not sure how to do this. Specifically, I would like to plot the line +- SD. An…
Anna
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How to set zero as the mean value when plotting a line graph in R of distance travelled per day

I'm trying to plot a line graph in R displaying distance travelled per day by an individual, with days on the x axis and distance travelled (per day) on the y axis. I want to set the value of zero so that it is equal to the mean distance travelled.…
he90
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Reading integer value from variable

Here I have a code and have a problem with stdev()the parameter length requires integer value which is stored in variable "bar". How can I make it read the value from a variable. //@version=4 study("My",overlay=true) numbars=1 t= time('D') if t…
Shubhz
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