# Questions tagged [standard-error]

For basic questions in statistics involving the properties or use of standard error of the sample points present in a simple random sample.

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### Cant find the error values correctly. Need Suggestions.

I have 6 observational data. $L_1,L_2,L_3,L_4,L_5$ and $L$. Each of them have seperate error values $\delta L_i$ and $\delta L$. All of these data are numbers such as $1.38e36, 3.45e33, 9.61e41$, ...
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### How to find the margin of error of a value consisting of the sum of 5 values? [closed]

I have a $X$ value that is the sum of 5 different $x1,x2,x3,x4$, and $x5$ values. Eacn $x_i$ has their error in same scale. I want to calculate the error of X. How can i do that? Basically, i tried to ...
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The following script is R code. ...
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### standard error of an estimate of fraction of objects with a known binary probability

Lets have a group of N people that can be either men M or women W (or in general objects that can be 0 or 1). For each person $i$ we have an estimate of probability $P_i$ from <0,1> that it is ...
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### Compute Sample Size for Specific Margin of Error & Confidence Level

I have a population that is in size equals to 65,536. The population follows a uniform distribution and is composed of discrete, ordered integer numbers. From this population I wish to identify the ...
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### Estimate standard error of population proportion based on one sample

There is a basket with unknown number of red balls ($N_r$) and green balls ($N_g$). I draw a random sample of $k$ balls without replacement and see that $P_r$ of the balls are red and $P_g$ of the ...
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### Why does multicollinearity increase the standard error of regression coefficients?

I understand the intuition that it is difficult to distinguish the effect of two independent variables on the dependent variable when they are highly correlated, but I don't see how this works its way ...
1 vote
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### Standard error on subsample

Suppose that I know that $N$ samples $(x_1, x_2,...,x_N)$ are iid drawn from a distribution with known variance $\sigma^2$. I also observe the first $k<<N$ samples, and estimate the mean on ...
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### How can I calculate p-values, t-statistics, and Standard Error for multiple regression by hand?

I'm attempting to calculate p-values and t-statistics for multiple regression, but all the resources I've been finding on the topic have confusing or inconsistent information. The best resource I've ...
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### Calculating with constants with tolerance

I have a formula. LogC= (LogA - 0.80 * LogB - 8.40)/0.50 However, all these constants 0.80, 8.40 and 0.50 have +/- tolerances which are not equal. Respectively, +0.13/-0.15, +4.55/-4.20, +0.12/-0.20. ...
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### Find between which values the 20% central will be at.

The measurements of the times of a group of children competing in a race of The 100-m dash follows a normal distribution with a mean of 13.4 s and a standard deviation of 1.2 s. Among which values ...
1 vote
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### Find the number of measurements so that our iuncertainty is less than 2%

The results of a certain experiment whose true value is about 10.0 cm, follow a normal distribution with standard deviation of 1.0 cm. How many measurements will we have to do so that our uncertainty ...
1 vote
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### Confusion about the import of the standard error

The standard error is defined: $$SD(\bar{X}) = \frac{\sigma}{\sqrt{n}}$$ where $\sigma$ is the standard deviation of the population and $n$ is the sample size. In the book I'm reading, it seems to ...
1 vote
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### $\varepsilon_{ij} \in \mathcal{N}(0,\sigma^2)$. What can we say about the third moment?

the errors $\varepsilon_{ij}$ are independent $\mathcal{N}(0,\sigma^2)$ random variables. What can we say about the third moment? For example, is $\mathbb{E}(\varepsilon_{ij}^3)$ bounded? I really ...
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### Ridge regresssion on a Echo State network

I am working with this article:http://www.scholarpedia.org/article/Echo_state_network on echo state networks. Here they speak about a ridge regression for the ESN. Normally the outputweight matrix ...
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### Getting the wrong expression for standard error

Here is the question: To estimate the proportion $p_1$ of male voters who are in favor of expanding the use of solar energy, take a random sample of size $m$ and set $X$ for the number in favor. To ...
1 vote
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### Average of Relative Error (Relative Error of a Sequence)

I have a sequence of ground truth and a sequence of measured values. Ground truth sequence: 4,5,3 Measured values sequence: 5,4,5 I would like to ...
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### Instrument resolution or Standard Error of the mean

Say I tried to measure the length of an object with an instrument that has a resolution of of 0.1mm and got the following: 12.5,12.5,12.5,12.5,12.5,12.5,12.5,12.5, 12.5,12.5 (all in mm). The standard ...
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### Help understanding the formula for relative error of a multivariable function

I am studying error theory. I don't understand from where does $\ln$ appear at the end Consequently, the marginal absolute error of the approximated value of the function $y^*$ is calculated by the ...
1 vote
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### logit and probit models

Basic background Hi, I'm relatively new to statistics and mathematics stack exchange so please bear with me. I'm trying to learn about the probit and logit models where the observables $y$ can only ...
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### Standard deviation formula for coefficients in multiple regression analysis

I am trying to understand how to calculate the individual deviation in this regression analysis table. $(HH Size)_{se} =$ $stderr \over \sqrt{S_{xx}}$ $=$ ${0.444400903 \over \sqrt{10}} = 0.14053$ ...
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### How to derive $SE(\hat{\beta_0}+\hat{\beta_1}x_0)=\hat{\sigma}\bigg[\frac{1}{n}+\frac{(x_0-\bar{x})^2}{(n-1)s^2_x}\bigg]^\frac{1}{2}$

I am trying to derive the following formula given by the lecture notes $$SE(\hat{\beta_0}+\hat{\beta_1}x_0)=\hat{\sigma}\bigg[\frac{1}{n}+\frac{(x_0-\bar{x})^2}{(n-1)s^2_x}\bigg]^\frac{1}{2}$$ My ...
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### Distribution of relative error.

Suppose I have a random variable $X$ with unknown mean $\mu$ and I can draw $n$ random samples (possibly from a Monte Carlo method, but I believe that's beside the point) from its distribution. I wish ...
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### How do I calculate this sampling error?

If I sample individual integer values $0$ to $100$ from a distribution $100000$ times and record the counts for all integer values between $0$ and $100$, how do I calculate the $95$% error bars for ...
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### Z Test and Standard Error

Before televised debates, a poll of 800 registered voters showed 560 in favor of a particular candidate; after the debates a poll of 600 voters showed 450 in favor of the candidate. A political ...
I am confused about the formula here about standard error. I know that standard error of the sample average Y_bar should be an estimator of the standard deviation of the sampling distribution $\bar Y$....
So I've been working on this question related to standard error and I managed to show that it can't be less than $1$. But how do you show that this has to be greater than $1$ (as in cannot equal $1$)? ...