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Questions tagged [standard-deviation]

Standard deviation (represented by the symbol sigma, σ) shows how much variation or "dispersion" exists from the average (mean, or expected value).

The standard deviation of a random variable, statistical population, data set, or probability distribution is the square root of its . A standard deviation close to 0 indicates that the data points tend to be very close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the data points are spread out over a wider range of values.

The standard deviation of X is the quantity

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Is there a way to find a deviation between a1=[] and a2=[] in Python?

We have these arrays in python: a1 = [0, 1, 2, 3] a2 = [0, 1.1, 2.2, 3.1] and want to find the deviation between a1 and a2. And sorry, we do not know what's such a type of deviation is named, but probably some of you do know.
akakakakakkaa
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Outliers in data

I have a dataset like so - 15643, 14087, 12020, 8402, 7875, 3250, 2688, 2654, 2501, 2482, 1246, 1214, 1171, 1165, 1048, 897, 849, 579, 382, 285, 222, 168, 115, 92, 71, 57, 56, 51, 47, 43, 40, 31, 29, 29, 29, 29, 28, 22, 20, 19, 18, 18, 17, 15, 14,…
Aaron
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MySQL for statistical results

I have a big task that I need some help with. My goal is the following table structure: type: type of car number_of_cars: number of cars for each car type number: number of people driving each car type average: average number of people driving…
malhel
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How do I find the standard deviation from a text file using python?

After finding the range, min, max and average from my text file of stored scores of my game, I would like to find the standard deviation from these scores but I am not sure how to go about it. This is what I have so far: file = open('stats.txt',…
Momo Sayeed
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Adding standard deviation to barplot() in R

In R I have the following dataframe: Group mean sd 1 1 21.2 5.202563 2 2 28.4 6.113737 3 3 21.8 2.529822 I would like to create a barplot with the means and the standard deviations as arrows on top of the means like this…
Afke
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standard deviation without mean c++

I have a functioning program to find the standard deviation of many integers. However, I am to find a way to get the standard deviation without the mean. I understand the formula is: std dev = sqrt [(B - A^2/N)/N] where A is the sum of the data…
Mark P
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Find any array of length N with standard deviation K

This problem was asked on ACM ICPC 2018 preliminary round. You have to print any array of length N whose standard deviation is K.
Harsh Vardhan Sharma
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Dynamic range into standard deviation formula

I need to calculate the standard deviation of returns in excel. I have monthly returns for a group of companies; lets say for company A, I have months 1 to 12 in 1995 and 1996 but for 1997 only months 1 to 7. I have a group of 2000 companies, they…
Silva
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In R language, how to calculate SD without using formula

I am trying to calculate sd using formula shew<-(sum((x-kl)^2))/(t-1) but result is wrong. I have tried calculating sd using SD function and result is different. can anyone help. IndexStart <- 1 x <- seq(IndexStart, 6, 1) x t<-6 xm <-…
Jals
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Mean and variance of gray level for an image set per pixel

I have 10 gray images of the same size. I would like to obtain the mean gray value and standard deviation per pixel in the image set. How can I do this?
Wasim Alqadasi
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what is wrong with my standard deviation calculation?

my code to find standard deviation is wrong. my code is supposed to find standard deviation from user input. i typed in the numbers 1 2 3 and the standard deviation of this set of numbers is 1 but it printed 10 where did i go wrong. also i know i…
Markus Wallace
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Three-way graph (variable, mean, sd) with ggplot2

I think I have an error in my logic while reproducing a graph I found in this pdf here. It should be fairly easy to do, but I have issues to plot a variable with its mean and standard deviation each in their own graph together, as can be seen in the…
Til Hund
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Python library to compute std dev of vectors

I have three feature vectors as : A = [1,0,1,0,0,0] B = [0,0,0,1,1,1] C = [1,1,1,0,1,0] Is there a python library that can help me compute the std dev of these ?
Rakesh Sharma
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Why does the compiler give an " java.lang.ArrayIndexOutOfBoundsException: x -error? (size depends on input)

I am making a small program to guess the keylength of a vigenere-cipher, with a given length between 5-15, within java. I do this by calculating standard deviations because of the transpositions. But my real question is why I get an out of bound…
Leon Pater
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C++ writing multiple strings from a file

Quick question. I'm doing my portfolio C++ question for a uni assignment. It is standard deviation. My question is to do with reading multiple strings from a file, see text here; Design and write a c++ program that reads a set of scores from the…
John Brown
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