Questions tagged [ratio]
the quantitative relation between two amounts showing the number of times one value contains or is contained within the other. Mathematically the quotient of one amount by another amount.
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How to estimate the standard deviation of a ratio?
I’m working with summary statistics (means, standard errors, and sample sizes) for two variables, and I’ve derived:
SD of variable A from its standard error and sample size
The ratio (P = A / B ) (e....
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Conceptual issues with using compositional data in model interaction term?
Can compositional data (seagrass % cover of multiple species - each value is mean of 10 1m^2 area per site) be used in an interaction term like this (and are GAMs somehow better equipped to handle ...
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Generalized Random Tesselation Sampling without a design-based estimator
I'm interested in using Generalized Random Tesselation Sampling to get a spatially balanced set of sample points in a study. However, the quantity I want to compute over the spatial area is a ratio, ...
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Could coefficient of variation be used on a ratio of two measurements? [closed]
I have length and width measurements for teeth (in cm), and have calculated a ratio of width to length as a means of comparing differences in tooth shape. Would it be viable to use coefficient of ...
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Can ratio variables be used in a regression model?
(Follow-up: Make certain terms in a regression model only apply to certain groups) I tried to write the model like this to avoid logical inconsistencies (e.g. distinguish between immigrants and ...
user443738
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How to calculate the confidence interval for the ratio between mean proportions
If one has data consisting of two groups of observations, where each observation is a proportion, how might one calculate a confidence interval for the ratio between the mean proportion in one group ...
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Use of Taylor series to approximate undefined mean
I would need your help to understand something about when it is appropriate to use Taylor series.
Say I've 2 normally distributed variables (X, Y). I understand that their ration (X/Y) would follow a ...
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Test the difference between the ratio of the coefficients a1 and a2 of a multiple regression and the ratio of another multiple regression
This question is related to the following question. Given the following multiple regression model.
$y∼N(a_0+a_1 x_1+a_2 x_2,σ)$... Regression 1
$y∼N(b_0+b_1 x_1+b_2 x_2,σ)$... Regression 2
where $y$ ...
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Propagate degrees of freedom from lmer model
I am not sure what are the correct degrees of freedom to use. I am interested in calculating whether the ratio of two slopes is significantly different than '3'.
I ran a linear mixed effect model such ...
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Expectations of estimators involving ratios
I'm studying some panel data econometric topics, and I've come across the following asymptotic properties as $N \to \infty$:
\begin{equation}
\theta^{\ast} \to \frac{\mathbb{E}(\beta_i)}{1 - \...
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Modelling a skewed response variable
I have a biomarker ratio (amyloid 42/40) and I am having issues modelling it. This is the proportion of a biomarker to another biomarker and it is important in diagnosing dementia. I am using as both ...
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Spurious correlation of ratios in per capita analyses
I'm trying to figure out how the spurious correlation of ratios impacts analyses where the variables are per capita measures.
Suppose I have a regression
$$
\text{GDP per capita}_{it} = \alpha + \beta ...
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Ratios when 0 denominator is possible
I've seen a few threads discussing something similar but I feel like my use case is a little different and doesn't fit the answers given.
I have records for digital usage where a user can use the web ...
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Testing for significance where results are expressed as a ratio to an in group control
I originally asked this question in the biology stack exchange site, but realise that it might be more relevant here in the stats site:
I have a large dataset that represents a library of yeast ...
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Monte Carlo simulations and Jensen’s inequality in cost-effectiveness analysis: point estimates vs. expected values of simulations
In cost-effectiveness analysis, we use a cost-effectiveness ratio: effect/cost. Because it is a ratio, calculating and representing uncertainty around it is not straightforward. We can use Monte Carlo ...
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