Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [adjustment]

This tag is ambiguous and should be avoided.

143 questions
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Is meta-analysis of odds ratios essentially hopeless?

In a recent paper Norton et al. (2018)$^{[2]}$ state that Different odds ratios from the same study cannot be compared when the statistical models that result in odds ratio estimates have different explanatory variables because each model has a…
COOLSerdash
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Adjustments to (Linear Regression) Forecast

Full disclosure: I am not a statistician, nor do I claim to be one. I am a lowly IT administrator. Please play gentle with me. :) I am responsible for collecting and forecasting disk storage use for our enterprise. We collect our storage use…
sbrown
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Would the real adjusted R-squared formula please step forward?

The following question, What is the adjusted R-squared formula in lm in R and how should it be interpreted?, presents different formulas for adjusted R$^2$, which were, Quote: Wherry’s formula: $1-(1-R^2)\frac{(n-1)}{(n-v)}$ McNemar’s formula:…
Carl
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Case-mix adjustment versus risk adjustment, what are their differences in practice and objective?

I have encountered in swathes of medical literature the use of the terms "case-mix" and "risk" adjustment without any citations or explanations of their exact usage and motivation from a modeling perspective. I understand the principles of covariate…
AdamO
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p-value correction for multiple t-tests?

My dataset consists of $n$ genes, each of them described by a vector of expression values, $5$ for "healthy" individuals, and $5$ for "unhealthy" individuals. I am going to run $n$ t-tests (one for each gene) to identify which genes show a different…
no_name
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Does adjustement completely remove the effect of the confounding variables?

This might seem a silly question but I am really confused about it. In theory adjusting for a confounder variable should remove its effect. Is this always true? and does this mean that the effect of this confounder variable we adjusted for has been…
JAMES A
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Significance testing when the treatment group was only partially treated (an unknown set of individuals did not receive the treatment)

I have a somewhat messy experiment that has already been conducted with large test and control groups, and have measured the response variables (sales / individual, etc). A known percentage of the 'test group' (supposed to be exposed to a treatment)…
KPTN
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Over-represented values in FDR-adjusted p-values

I have a vector of p-values that need correcting for multiple comparisons; based on reading Noble (2009), I am attempting to apply a Benjamini-Hochberg FDR-based correction. My vector (sorted in ascending order for ease of visualisation) is: ps…
ecologysarah
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Adjusting time-series before a sudden increase(the reason & time of the increase are known)

There are 2 increases in magnitude (one between feb and march, and one at the beginning of september) (the chart has daily resolution btw) Assuming weekly seasonality, is it ok to get the exact day when the increase was noticed and the day 1 week…
wsdookadr
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Converting Adjusted Odds Ratios to its RR counterpart

I am doing a meta-analysis of studies which reported their estimates sometimes as OR and sometimes as RR. I wanted to convert the OR to RR, so that I can pool them together. I know that I can use this formulas for unadjusted odds $$\text{Relative…
Amirhossein Modabbernia
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How to make adjustment for correlation coefficient?

Suppose that there are two two-dimensional maps. For simplification, let's say one map is the temperatures in the 48 continental U. S. states, and the other map is the corresponding humidities. The data of temperature and humidity are collected at…
bluepole
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Should all adjustments be random effects in a mixed linear effect?

I've been sometimes taught that when you are performing a mixed model, any variable of which you don't care about estimating a parameter (adjusment variable) should be a random effect, regardless of number of added degrees of freedom. However, in…
Dan Chaltiel
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ARIMA, adjustments and intervention analysis

I have very little knowledge of time-series analysis (despite my stat master - didn't do anything else than an introductory course) but now I'm facing a statistical problem whose answer is this very kind of analysis - so would really need a helpful…
1two3stats
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P-value correction for multiple testing using huge datasets

First of all I apologize without the question is very basic, I am taking my first steps in data science, statistics and bioinformatics. Data information We are evaluating the correlation (using the Pearson, Kendall or Spearman method) between gene…
Genarito
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Why match if you have the control data already?

I had a question about matching. I understand the benefits of matching prior to conducting a study due to potential increases in statistical efficiency/ adjustment for confounders. Let's say you're conducting a retrospective study where you have a…
StatisticalPig
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