Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [coefficient-of-variation]

A measure of dispersion expressed relative to the mean, used for positive variables. Equals the standard deviation divided by the mean.

155 questions
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How to quantify variation within one experiment?

Given a couple of measurements I get by running an experiment, I need to express the fact that they are similar to some extent. So, I computed their coefficient of variation, i.e., stdev/mean. Here is a sample: 3.76025 2.98375 3.78946 3.72195…
DED
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Cut off values of the coefficient of variation in determining whether to include/exclude a sample

I'm fairly new to statistics and could use some advice. I have 70 blood serum samples that have had metabolite concentrations tested twice. (Same blood draw, different test dates). I calculated the average, the standard deviation and the coefficient…
Bart
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Alternative to coefficient of variation (CV)/relative standard error as a measure of estimate's reliability/stability

I am seeking a statistic measuring an estimate's reliability or stability as an alternative to the coefficient of variation (CV), also known as the relative standard error. The CV is the standard error of an estimate (proportion, mean, regression…
David Radwin
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How to deal with duplicates with high coefficients of variation

I am working with raw data from a multiplex Luminex assay ( not by commercial kit); I have found that some duplicates have a high %CV. I would like to know if you can advise me on dealing with this data (I can't remeasure these samples). I describe…
BRUMJ
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Can the coefficient of variation for two samples be added?

I have a quick question that should hopefully require a quick answer (my apologies if this is a rather simple question). I have two estimates of relative abundance from two sub-populations and want to sum them to obtain one overall number. Being…
user13317
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Can coefficients of variation be compared if the samples differ in size?

I have to do a study for trying a sanitary product that has an acceptance criterion for the %CV repeatability and %CV reproducibility of the measurands. The acceptance criterion of the performance of this product is based on %CV and the cut-off was…
Laura Santulario Verdú
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Can I compare the average coefficients of variation?

I have two datasets. The first shows a populations choices for mode of transport (3 modes) in 6 different areas. The second shows the same populations responses to concerning attributes (13 attributes) in their public transport experiences across…
Andrew Earl
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Generalised coefficient of variation?

Consider the CV for a given random variable $X$: $$ CV_X = \frac{\sigma_X}{\mu_X}$$ Now, say I also have random variable $Y$. Let us define: $$ CV_{X,Y}= \sqrt{\frac{\text{Cov}(X,Y)}{\mu_X \mu_Y}} $$ So far I have found these properties of the…
luchonacho
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Alternative for coefficient of variation due to negative observations

I have several measurements of trees over time (different vegetation indexes). Each measurement is in a different scale, some also include negative values (e.g. NDVI). I need to compare the variation in time of all measurements, using a single…
Gilad Weil
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How do I calculate the cv for observation errors from a time series of actual values and a time series of values with observation error?

I have a time series of actual values. I also have a time series consisting of values with observation error. Assuming that the observation errors are normally distributed, independent of one another and are proportional to the actual values, how…
Kneef
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Alternatives to Coefficient of variation

I have a set of temperature datasets all from different products. I wish to calculate the variation in the products. I have tried using coefficient of variation. But because the temperature data varies from say 20-40 deg C, the mean would be high…
Keerthi
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Coefficient of variation question?

Is it appropriate to compare the coefficient of variation between discrete (e.g., clutch size) and continuous data (e.g., egg width)?
user82580
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Coefficient of variation for % increase

I was reading about the coefficient of variation and it seems that it can only be computed for ratios (non-negative values). I have a list of values which indicate the % increase in a particular quantity. In certain rare cases, there is a decrease,…
user67813
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Combined Coefficient of Variation

I am doing a research in 12 participants where I perform two different techniques three times each, at different moments. I would like to calculate the combined CV (Mean CV1 + CV2 + CV3), but I don't know if this is statistically possible, and the…
Marco Pinto
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Using coefficient of variation in lab testing

In order to determine the accuracy of a specific method, I need to determine if the results are statistically precise. In the example below, I am taking a sample from 7 individuals and running their sample twice. For each row I calculated the mean…
J.E8231
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