Questions tagged [logarithm]
The logarithm of a number is the power to which the base must be raised to get the number.
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Back-transformation and interpretation of $\log(X+1)$ estimates in multiple linear regression
I have performed multiple linear regression analyses with different combinations of transformed and untransformed variables--both explanatory (independent) and response (dependent) variables. All ...
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Interpretation of log transformed predictor and/or response
I'm wondering if it makes a difference in interpretation whether only the dependent, both the dependent and independent, or only the independent variables are log transformed.
Consider the case of
<...
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How can I sample from a log transformed distribution using uniform distribution?
I am transforming an unscaled density function to log scale to avoid underflow issues.
BI was performing integration on this function on a grid of values before I used the log transormation, to ...
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Math Statistics Bell Curve Computing % correct given 2 numbers (C#) [duplicate]
Possible Duplicate:
Computing per cent correctness from a bell curve
I've been trying to remember my High School teachings and are falling short.
I'm working on a project where I need to give a %...
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How to log transform Z-scores?
The data for my variable is in the form of Z-scores only. I'd like to log transform the scores, but I don't know the mean or standard deviation in order to covert to raw scores. Can I assign an ...
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Software to plot a log graph
I have to plot a graph with log distribution on y axis. The values are: 10^-3..10^3.
What software do you suggest me to use.
My OS is Ubuntu, so I prefer software for Linux.
Thanks.
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Advice on identifying curve shape using quantreg
I'm using the quantreg package to make a regression model using the 99th percentile of my values in a data set. Based on advice from a previous stackoverflow question I asked, I used the following ...
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The estimated logarithm of the hazard ratio is approximately normally distributed
According to this document: The estimated logarithm of the hazard ratio is approximately normally distributed with variance (1/d1) + (1/d2), where d1 and d2 are the numbers of events in the two ...
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Log-scale with concentrated data using integers
I have a data set with a range of 0 to 65,000. The vast majority of data points (it is a huge sample) are concentrated between 0 and 1000. There is only one point that has 65,000. I want to plot ...
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Log graph question
So let's say you have a distribution where X is the 16% quantile. Then you take the log of all the values of the distribution. Would log(X) still be the 16% quantile in the log distribution?
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How do you calculate the standard deviation on a multiplicative scale for a distribution that has been transformed logarithmically?
I know the value for the 16% quartile, so I know the additive deviation for the given distribution. How do I find the deviation of the log of the given distribution on a multiplicative scale?
Justin Meltzer
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What are alternatives to broken axes?
Users are often tempted to break axis values to present data of different orders of magnitude on the same graph (see here). While this may be convenient it's not always the preferred way of displaying ...
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Why (or when) to use the log-mean?
I am looking at a scientific paper in which a single measurement is calculated using a logarithmic mean
'triplicate spots were combined to
produce one signal by taking the
logarithmic mean of ...
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In linear regression, when is it appropriate to use the log of an independent variable instead of the actual values?
Am I looking for a better behaved distribution for the independent variable in question, or to reduce the effect of outliers, or something else?
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