Measurement error is the difference between a measured value of a quantity and its true value.

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15 views

How do you report percent error with limited precision?

Let's say you have an experimental data point with limited precision, such as 0.67 ± 0.1, and a known actual value such as 0.72. What is the standard way to report the percent error in this case, ...
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13 views

How should I handle measurement error in logistic/probit regression and what are its effects?

I am concerned with the problem where dependent discrete variable $R$ is to be modelled by continuous predictor $X^*$, which is subject to measurement error $u$ of the form $$X^*=X+u$$ ($X$ being the ...
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28 views

Accounting for measurement bias using a histogram or violin plot and numerical data in R

The Problem I have a gardener whose job it is to measure trees in meters using a measuring stick. She measures the heights of 1,000 trees. I plot these measurements on a violin plot in R. I am ...
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1answer
45 views

non-classical measurement error in a binary outcome model

I have a binary outcome model that I am estimating with a probit, so $$\Pr(Y=1\vert x,z)=\Phi(\alpha +\beta\cdot x^* + z'\gamma)$$ I am interested in the marginal effect of $x^*$ on $\Pr(Y=1\vert ...
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1answer
97 views

Additive Error or Multiplicative Error?

I'm relatively new to statistics and would appreciate help understanding this better. In my field there is a commonly used model of the form: $$P_t = P_o(V_t)^\alpha$$ When people fit the model to ...
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1answer
15 views

IV or latent factor to process multiple measures?

I have several measures on different memory tests. I consider these measures may actually measure different aspects of memory functioning and every measure contains a measurement error. I am thinking ...
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21 views

Robust Measures for Forecast Accuracy

I am doing a forecast using robust exponential smoothing methods and to determine / measure the forecast accuracy I want to use robust measurements as well. As I am not really familiar with robust ...
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45 views

Machine learning/random forests with noisy response data

Machine learning techniques like random forests seem to assume that the responses in the training set are known perfectly. Specifically for regression applications, it seems one needs to account for ...
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1answer
69 views

Accounting for unknown error in multiple regression?

I have a very naive question about multiple regression and errors...one that isn't addressed here already (Choosing a robust estimator to account for measurement error in dependent variable) I would ...
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28 views

does the area under the curve (AUC) has some interpretation? [duplicate]

I know that the ROC curve plots true positives vs false positives, but does it have any other interpretation, or is it just an arbitrary performance measure? Also, in the case of very unbalanced ...
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12 views

Need to determine stability of a measure over subsets

I have a measure that takes a set of data and spits out a value. I want to determine the stability of this measure in terms of the size of the dataset. I.e, I want to understand how the returns (for ...
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34 views

Measurament error from semivariogram

I am looking at a model to determine the measurement error for a set of measurements of a spatially correlated phenomenon (sea surface temperature measurements) using a semivariogram technique. For ...
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31 views

Fast Estimation of Random Effects with Measurement Error

Let $Y_{i}$~$Normal( Z_{i} , \sigma_{i}^{2})$ and $Z_{i}$~$Normal(0,\tau^{2})$, where $Y_{i}$ is a measurement, $\sigma_{i}$ is known measurement error, $Z_{i}$ is the unknown latent variable I want ...
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18 views

Combining separate accuracy and precision calculations for characterizing the performance of a device

I have created a device that produces chemical mixtures of user-defined concentrations and am now working on characterizing the performance of this device. In order to do this, I created 3 replicates ...
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1answer
32 views

Interpreting a logarithmic difference as an error

This is a fairly simple question but I can't figure out which one is the correct approach. In astronomy it is usual to report age values via their base 10 logarithms instead of the actual value. So a ...
4
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1answer
45 views

Intuition for what happens to the standard deviation after plugging a normal variable into a function

Let's say I have a normal variable $X$. I feed $X$ into some function, which applies varies mathematical operations to it - for instance, addition, subtraction, multiplication, division, $x^r$, $e^x$, ...
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16 views

How to separate model errors from measurement errors?

I've got data measured with errors that have known measured_RMS. I am testing a model that has model_RMS differences between model prediction and measured data. What would be a reasonable estimate of ...
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11 views

Using confidence level for error evaluation

I want to evaluate performances of a forecasting system. I have some samples of the whole population. But what i actually have is the mean value of the sample and the forecast for the mean of the ...
2
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1answer
58 views

Difference in 2 groups when group assignment is not certain

Suppose you have two groups and you want to see whether these two groups differ in regards to some variable. This sounds like a basic t-test or perhaps non-parametric Wilcoxon rank sum test. Suppose ...
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6 views

How to properly calculate error in a decompressed column of floating point numbers?

I have a series of floating point numbers, compress it with some lossy compression algorithm and decompress it. I want to be able to calculate the error produced by this procedure. What I've done is ...
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17 views

Error in standard deviation and variance from error in data

I have a set of datapoints $x_i$ which have known upper bounds for absolute errors $\delta x_i$. (To clarify, this means each $x_i$ is actually $x_{i_0} \pm \delta x_i$). For simplicity, assume that ...
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1answer
35 views

What is Median Error Distance and how to calucalte it

How to calculate Median Error Distance? I'm looking at "Schulz A. et al. A Multi-Indicator Approach for Geolocalization of Tweets". They are calculating Median Error Distance. But how they are do ...
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18 views

Distribution of average and median of a random variable [duplicate]

Suppose I have some random variable, which is defined by certain distribution (e.g. triangle or normal or some other). Suppose I do $N$ independent measurements on this random variable and then ...
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29 views

Measurement Error in Dynamic Linear Model

I have fitted a dlm model as follow: ...
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17 views

Tools for determining final error with mixture of correlated and independent sources of error

Preface: Not looking for an answer, but rather seeking an approach or set of approaches to deal with a complicated problem. Brief version: I have a single, analytical set of 3 equations with 8 ...
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1answer
17 views

error summary metric

I am working on trying to get a summary metric that summarizes the results of four models (M1:M5) and preferably ranges from zero to one, with one being the best model and zero being the worst model. ...
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103 views

Estimating the uncertainty of a bias and a scatter

I have one single set of observational data. Assuming I know the right answer for one property of this data set and then I use one tool to measure this quantity. To get an estimate of the amount of ...
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1answer
71 views

Selecting priors based on measurement error

How do you calculate the appropriate prior if you have the measurement error of an instrument? This paragraph is from Cressie's book "Statistics for Spatio-Temporal Data": It is often the case ...
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16 views

How do you scale percentage intervals based on absolute size?

If you were told the travel time from A to B is 5 minutes, you wouldn't mind if it took between 0 and 10 minutes. So happy within 100% of 5 minutes. If the trip took 5 hours (360min), you wouldn't ...
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14 views

logarithmic calibration and geometric mean - citation search

I have a logarithmic calibration line: MachineSignal = -3.21 log(concentration) + 21.9 It seems obvious to me, that if I have a triplicate measurement of concentrations (measured indirectly through ...
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19 views

Paired data with independent groups of treatment, how to plan and analyze?

I need your assistance, I am trying to design an experiment, and in order to do so I need to know how the data will be analyzed. The experiment in on rats. Each rat gets some treatment, and a measure ...
3
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1answer
77 views

Weighted principal components analysis

After some searching, I find very little on the incorporation of observation weights/measurement errors into principal components analysis. What I do find tends to rely on iterative approaches to ...
2
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0answers
56 views

Using least squares straight line fitting on experimental data with errors

I'm trying to fit a line into a graph with points that have errors both in the y and x directions. I found the following document on the subject: https://www.che.udel.edu/pdf/FittingData.pdf My ...
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15 views

measurement sampling error and heteroskedasticity

I was reading: A potential problem arises from the fact that the measurement (sampling) error associated with the regression beta may vary cross-sectionally. This may introduce heteroskedasticity ...
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36 views

What is task-loss function?

I looked into "Multi-Output Learning for Camera Relocalization" research and faced with the following part (2.2 The Direct Regression Approach): Given a set of RGB-D frames with known camera poses ...
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1answer
30 views

How I can measure an error in a bar plot?

This is my barplot. Model(red) is my estimated frequency at each X-axis vale (0-19) and actual is the frequency at each X-axis vale. How I can measure error of this estimating work in barplot? If I ...
0
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1answer
16 views

Is it possible to extrapolate experimental errors from a subsample of a population?

I'm working with a dataset consisting of degradation rates for proteins in an organism, a total of approx 3750 rates in total. Obtaining these rates is difficult, so the majority of rates are reported ...
2
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1answer
90 views

How to use factors (from CFA) as independent variable in Regression Analysis

I calculated 4 factors as latent constructs in a Confirmatory Factor Analysis (I use AMOS). Now I am wondering if it is possible to extract some kind of a factor score like I know it from Exploratory ...
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33 views

Evaluating mean-squared error

Hello I am running a Regression Tree experiment. I am new to Regression Trees, and I am using Mean Squared error to test my tree. I am confused because I am getting a large Mean Squared Error but I ...
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1answer
75 views

Implication of mutual information

EDIT For two signals or random variables to be independent, the mutual information (MI) must be zero. What does mutual information (MI) convey? What is the meaning of independence? Does it mean ...
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1answer
62 views

Are significance tests only about sampling error or other forms of variation also?

When we study differences between a treatment and control group in an experimental setting, we want to test whether those differences are big enough that we can conclude they are not simply due to ...
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1answer
159 views

Estimate average percentage error based on another gaussian measurement

I have a model where the error is proportional to the throughput. This is, the observations I got come from a measurement instrument that has some error and it measures material going through in ...
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748 views

using Root Mean Squared Error (RMSE) to compare models with different sample size

I'm using k-fold cross-validation to compare different models. I splitted my dataset in 6 chunks and used 4 random chunks as training set and the remaining 2 as a test set. Now I fitted n-different ...
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98 views

Performance of hierarchical clustering for binary data in R

I am trying to use Hierarchical clustering to see how well it performs in classifying a dataset which I previously know its true classification. I am new to clustering in general. I was able to draw ...
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37 views

What's the sample size required to confirm that two treatments are identical?

Goal: Determine if a machine is defective Say I am going to give the same treatment to a group of people. I have a machine that will randomly split them into $2$ groups before giving the same ...
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2answers
145 views

Standard deviation for a measurement that has two causes of uncertainty

I would like to know how to calculate the standard deviation for a measurement value $x$ when there are two separate sources of uncertainty, 1 and 2, each with known standard deviation, $\sigma_1$ and ...
2
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1answer
65 views

larger sample size or more accurate measurement?

This question is completely theoretical in the sense that I don't have any real data. Suppose I am designing a study, in which I will go measure N pairs of (X,Y), then the goal is to build a ...
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0answers
58 views

Significant digit 354 rule from Particle Data Group

The particle data group (PDG) has a particular rule to round the value of a measurement. You can find the complete description at this link (page 13). Summarizing: ... if the three highest order ...
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171 views

Linear regression model that best suit for data with errors

I'm looking for linear regression algorithm that is most suitable for a data whose independent variable (x) has a constant measurement error and the dependent variable (y) has signal dependent error. ...
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23 views

Parameter estimation of LMM with multiplicative measurement error in fixed co-variate - How?

I have a linear mixed model, with multiplicative measurement error on the fixed co-variate only (i.e. the random part is assumed to be measured without error). How could I best estimate the ...