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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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plot error bars

Is there a function in R that does the following thing: Taken c(10,11,20,22,30,31) and c(1,1,2,2,3,3) plot the mean of 10 and 11 in position 1 on the x axis, the mean of 20 and 22 in position 2 on the x-axis and the mean of 30 and 31 in position 3…
Remi.b
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Standard deviation of combined data

I have a data set with mean values, standard deviations and n. One of the variables has an equal sample size, while the sample size for the other one varies. dat <- data.frame(variable = c(rep("x", 2), rep("y", 3)), replicate = c(1,2,1,2,3), mean =…
Mikko
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MATLAB error: "previously appeared to be used as a function or command"

I want to create a function called E7stats, which performs a simple statistical analysis on the scores of the first midterm, contained in a csv file. The function takes one string input, filename, which is the name of the csv file, and returns one…
Ajay Kejriwal
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How to compute intraclass standard deviation without loops in matlab?

I have a data set with n samples d features represented by a n*d matrix. The corresponding label is a n*1 vector. How can I compute each intraclass standard deviation without loops in matlab? For example: Samples 5 1 1 1 4 5 2…
liu
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Awk Rounding of Value Field Based on Significance of Second Rounded Field

I want to take the following input Average Box 1: 0.520522 Std. Dev. Box 1: 0.00297154 ...print the first number (the average) rounded to a certain digit, where that digit is defined by the first significant digit of the ROUNDED std. dev. e.g. -->…
Jason R. Mick
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awk search and calculate standard deviation different results

I am working to take the output of sar and calculate the standard deviation of a column. I can perform this successfully with a single column in a file. However when I calculate this same column in a file where I am stripping out the 'bad' lines…
user1601716
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For-loop to read multiple .csv files in Python

I started using Python and have the following problems here. Indentation Error with count +=1 and several other lines Not scanning all .csv files in a directory. When I run this script, it only shows outputs of only one .csv file instead of…
Python_R
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solving standard deviation for a gaussian random variable

So lets assume I have a Gaussian random number generator that takes 2 parameters std deviation and mean, X(d,m). What I want to do is specify the std deviation for the number generator such that i get a random number in a given range 95% of the time…
Andy McCall
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Outlier detection Stata with standard deviation in time series

I have a dataset of 10 participants. These participants conducted different walking tests and physiological responses (i.e., heart rate, breathing frequency) were collected. I want to detect outliers with a 3 standard deviation rule in Stata. What…
Sophie
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finding standard deviation giving me "java.lang.ArrayIndexOutOfBoundsException: Index 10 out of bounds for length 10"

my specific problem is where I try to calculate the Standard deviation. I looked up how to do this and found a code online that would work. when I implemented it and ran it I got the error. Exception in thread "main"…
bran
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Is there another simplier way to obtain median in R?

I´m asked to obtain the life_expectancy median per region: Gap %>% group_by(region) %>% summarise(Median = median(life_expectancy)) But also, mean and standard deviation. Is there another function simplier that writing all this…
Lucia Langenheim Hernández
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I want the standard deviation calculated in minutes

My dataset is in hours and I need guidance on how to convert the standard deviation from hours to minutes. In the code provided under, I only get the standard deviation for hours. How can I convert it to…
Svein
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Google Maps SQL Server : calculating outlier geographic data within group

There are 100 suppliers, each with between 50 and 1000 items. Each supplier may have items close to their office or spread across an entire country or continent. As LatLngs are input by a human, some mistakes happen. With lots of data and constant…
user2470281
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Converting one-pass StandardDev formula from C to Python

I am trying to convert the following one-pass standard deviation code in C to Python: double std_dev(double a[], int n) { if(n == 0) return 0.0; int i = 0; double meanSum = a[0]; double stdDevSum = 0.0; for(i = 1; i < n;…
Lance Gibson
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Positive random number generation with given mean and standard deviation

I am working on a simulation project. Need help on random number generation. I need two sets of random numbers. Properties: Primary set (var_a) > Normally distributed, greater than 0, with given mean and std. Secondary set (var_b) -> Same as a…
Sarabjeet Singh Hanspal
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