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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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how to get standard deviation of an aggregate of all values of a dataframe (or matrix), grouped by one variable

I have a data frame with 13 columns. the 13th column shows the group number each row belongs to. I want to take the standard deviation of all values in all rows of columns 3 to 12, for rows of each group. for(i in 1: groupnumber) { sd.vect[i]…
Mathica
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Caculate the standard deviation be for the vatiable in the matrix created by tensorflow

import tensorflow as tf input=[50,10] O1 = layers.fully connected(input, 20, tf.sigmoid) Why my input is wrong?
Edward Chailey Smith
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What is the =stdev equivalent in R?

I am trying to calculate the standard deviation for each participant across certain columns (or variables) and have this as a new variable in my dataframe. In Excel, it's relatively simple, you would just use =stdev and then select the columns you…
helpme
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Calculating standard deviation for defined values in a dataset error in R

I want to calculate the standard deviation for x = [1:15], [1:1000]. I am looking for a way to get the standard deviation for every group of 15 - so 1000 standard deviations in total, but i cant find a formula for it.
nebbdyret
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Calculations have me stumped

I'm working on a calculation code that needs to calculate a number between the first input to the final number(second input). When I do it creates this: What is the first number? 45 What number do you wish to go to? 50 Sum of numbers between 46 and…
speedforce
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don't know whats wrong stddev func line couldn't solve it, can you please advice me. TypeError: unsupported operand type(s) for -: 'tuple' and 'float'

So I am trying to define function to calculate mean and st.dev (without packages) of a given series of numbers, also the function must be provided with a minimum of 2 numbers, where *arg means I can use any list of numbers>1 def…
Maria
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Calculate average and standard deviation for pre defined number of values substituting missing rows with zeros

I have a simple table that contains a record of products and their total sales per day over a year (just 3 columns - Product, Date, Sales). So, for example, if product A is sold every single day, it'll have 365 records. Similarly, if product B is…
Chipmunk_da
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Xcode performance test case

I have the below lines of code for which I need to test the performance criteria. But unfortunately Apple Document does not help to get a clear understanding on this. func addStrings() { let maxCount = 100000 var array:Array =…
NNikN
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R Finding standard deviation of other column based on binned groups

Hi I have a dataframe with three columns: a name column, a numerical column A and a numerical column B. What I am trying to do is bin the rows by their values in column A, and then find the standard deviation of each binned group's values in column…
hamhung
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Standard deviation for the difference of two dataframes with group by

I have two panda DataFrames: Dataframe Yahoo: date ticker return 2017-01-03 CRM 0.018040121229614625 2017-01-03 MSFT -0.0033444816053511683 2017-01-04 CRM 0.024198086662915008 2017-01-04 MSFT …
Alfonso_MA
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How to plot mean and standard deviation using CSV file?

I want to plot mean and standard deviation like here using input CSV file as: index mean std 0 0.5 0.04 1 0.7 0.17 2 0.6 0.08 3 0.3 0.13 4 0.9 0.02 5 0.5 0.01 I tried the exam showed in that post but i could understand…
Bilgin
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How to generate random x and y coordinates using box muller transformation

I'm attempting to generate random x and y integer values within a certain range (roughly -10 to +10) using a box muller transformation. I've logged a dataset and calculated my standard deviations for each axis as sdX = 4.413680773 and sdY =…
Keegan Heffernan
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Deviation of a list from a reference value

I've got a reference value: ref = 0.5 And a list: my_list = [0.4, 0.5, 0.6, 0.5] I'm trying to calculate how much, on average, the elements of my list differ from my reference value. Basically, it would be the same as a standard deviation, but…
Notna
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Calculate the standard deviation of a cluster of datapoints

So, I have a list of data points where all of them belong to a cluster(Each item is a numpy array with 3 features(represnting a point)). I compute their centroid (mean of the points). I want to calculate the standard deviation of a point from the…
VAMSHI KRISHNA SAI NAGABANDI
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"dot plot" relative to the mean with standard deviation

In the attached graphic the dots mean the average value of selectivity of each specie. In this plot, I would like 1) to have larger font sizes of the smaller dots referents to the smaller body mass (bodymass<9Kg). I wanted to reduce the scale of…
Fran Braga
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