Linked Questions

I am trying to log transform time series data of Inflation. However, there is one negative value. I have added the constant 1 to all my values and the log transformed. ...

I am apply log-normalization to my non-normal data. However, when I apply log-normalization, the 0 values is converted into inf, which makes it impossible to apply ...

I have a skew variable and I want to use box-cox transformation (log) but around 50 observation out of 200 are between 0 and 1. My initial thought was to add a constant to all observations before ...

I am doing some explorative work on two large datasets. One from 2001 and one from 2018. The dataset consists of measured soil-parameters and it contains lots of zero's. From the transformations ...

My current model is of the form $$\log(\frac{y_i}{1-y_i}) = \beta_0 + \beta_1 x_1+\beta_2 x_2.$$ Is it okay if I consider the model $$\log(\frac{y_i}{1-y_i}) = \beta_0 + \beta_1 x_1+\beta_2 \log(x_2+1)...

What is your favorite statistical quote? This is community wiki, so please one quote per answer.

If I have highly skewed positive data I often take logs. But what should I do with highly skewed non-negative data that include zeros? I have seen two transformations used: $\log(x+1)$ which has the ...

When transforming variables, do you have to use all of the same transformation? For example, can I pick and choose differently transformed variables, as in: Let, $x_1,x_2,x_3$ be age, length of ...

Lets say I have three independent sources and each of them make predictions for the weather tomorrow. The first one says that the probability of rain tomorrow is 0, then the second one says that the ...

I am thinking of building a model predicting a ratio $a/b$, where $a \le b$ and $a > 0$ and $b > 0$. So, the ratio would be between $0$ and $1$. I could use linear regression, although it doesn'...

I have ran a QQ plot on R on my data using par(mfrow=c(1,2)) par(pty="s") qqnorm(TEDS$LST1); qqline(TEDS$LST1) which gave me this: The histogram of the data ...

I have a question about the correct distribution to use for creating a model with my data. I conducted a forest inventory with 50 plots, each plot measures 20m × 50m. For each plot, I estimated ...

I have a dataset comprised of continuous values that have about 30-50% zeros and a large range (10^3 - 10^10). I believe these zeros are not a result of missing data and are the result of the ...

I'm working with linear mixed-effects model in Stata. Dataset has three levels of 100k observations, nested in 500 regions, nested in 70 regions. Currently my modelling strategy is to use three-...

Possible Duplicate: How should I transform non-negative data including zeros? Error in boxcox.default(y ~ x) : response variable must be positive I want to perform box cox transformation on ...