--- title: "Data Transformation in predmicror" output: rmarkdown::html_vignette vignette: > %\VignetteIndexEntry{Data Transformation in predmicror} %\VignetteEngine{knitr::rmarkdown} %\VignetteEncoding{UTF-8} --- ```{r, include = FALSE} knitr::opts_chunk$set( collapse = TRUE, comment = "#>" ) ``` ## Consistent Use of Natural Logarithm In previous versions of `predmicror`, there was an inconsistency in the required data transformation for different models. Some models required the data to be in natural logarithm (`ln`) scale, while others required it to be in base-10 logarithm (`log10`) scale. This could lead to confusion and errors. To address this issue, all models in `predmicror` have been harmonized to use the **natural logarithm (`ln`)** for the response variable `Y(t)`. This means that users should always provide the microbial concentration in `ln` scale. ### Converting from `log10` to `ln` If your data is in `log10` scale, you can easily convert it to `ln` scale using the following formula: `ln(N) = log(10) * log10(N)` Here is an example of how to convert a column in a data frame: ```{r} # Create a sample data frame with log10 data my_data <- data.frame( Time = c(0, 1, 2, 3), log10N = c(2, 2.5, 3, 3.5) ) # Convert the log10N column to lnN my_data$lnN <- log(10) * my_data$log10N # Print the updated data frame print(my_data) ``` By ensuring that all models use a consistent `ln` scale, `predmicror` is now more user-friendly and less prone to errors.