Questions tagged [interquartile]
The interquartile range or midspread is a central interval containing 50% of the data, eliminating the 25% smallest and 25% largest observations.
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Why divide data into 4 parts for IQR, and not into parts of 20 or 10 percentages each?
Why divide data into 4 parts for IQR, versus into more parts, such as 20 or 10 percent per part?
I know that interquartile range by definition means 25%, but that is not my question.
I think that ...
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How do I regress income quartiles against each other?
I'm looking to find out whether an attitude differs across income quartiles. My supervisor has mentioned dummy coding and regressing the quartiles against each other, however, I'm sort of at a loss as ...
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Are there cases where we need to avoid the usage of IQR?
Let's consider the interquartile range (IQR), the standard deviation (SD) and the mean absolute deviation (MAD). We know that "one of the most common robust measures of scale is the interquartile ...
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BEST POSSIBLE WAY to determine significantly high values within zero-inflated univariate continuous distributions
I have more than 50 different distributions, corresponding to 50 different kind of customers, who spend their money in a certain way within a period, being this amount the single variable of interest.
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Interquartile range when back-transformed mean on log-scale is not equal to median on normal scale
I have 2x10 observations that follow a non-normal distribution. They are perfectly distributed on log-scale.
From what I've learned, the back-transformation of the mean on log-scale should be a "...
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Asymptotic efficiency of IQR
I was wondering about the asymptotic efficiency of the Interquartile Range (IQR) in the Gaussian case. I have calculated it empirically using a Monte Carlo estimator, and it appears to be equal to ...
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Calculating Change in OR per increase from the 25th to 75th percentile (IQR)
I have a dichotomous outcome variable (ever disease) and a continuous exposure variable (chemical). I have already run the logistic regression for the ln exposure and gotten the odds ratio. However, ...
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Replacing outliers with the median value of the preceding 5 observations
In the paper Implications of dynamic factor models for VAR analysis the authors propose a a technique for removing outliers in variables used for dyanamic factors analysis:
"The outlier ...
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Calculating descriptive stats for aggregate/binned data [duplicate]
I have several datasets that I wish to analyse and summarize - and I'm starting with the basic median, and percentile/quartiles to begin with (unless there are other approaches I should be considering)...
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Why is the Tukey's IQR not used in the R program?
I was writing an R Markdown for calculating measures of spread and was surprised to find that the IQR function does not use the IQR calculation I am used to using, ...
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Comparing averages of non normal distributions
I want to compare the daily average revenue of a promotion period (7 days) of a business with the daily average of the rest of the year.
So, sample 1 has 7 data points, whereas sample 2 has 300 data ...
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May the cumulative distribution function be used to calculate the inter-quartile range and vise-versa?
May the cumulative distribution function be used to estimate the inter-quartile range?
I am drawing their similarities.
The IQR is found via a boxplot which has percentiles. A percentile comes from ...
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Interquartile ranges of 2 groups in meta analysis
I am performing a meta analysis of mutliple trials (Intervention vs. Placebo) and wanted to describe the baseline characteristics in a table.
Some trials report continous variables as medians and ...
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Standard deviation on Bimodal data
Standard deviation, whilst it is often used on normal distributions, is it a useful statistic on global temperature, both daily and yearly, given that weight of the data is towards the ends of the ...
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Is it possible to calculate median value and interquatile range for a set of numbers containing a range or inequalities?
I am trying to make simple median and IQR calculations that involve numbers (in percentages) appearing in a range and inequalities in addition to whole numbers. My sample dataset looks like this:
5, ...
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