I have a specific question about indicator/ dummy variables in a model. Right now, I have a set of data over about a year, with various variables such as temperature and operational units. Also in this are indicator variables to indicate things such as 0 or 1 for production day/ non production day. These are all then used in excel using linear regression. I have been trying to research the statistical validity of this, specifically using indicator variables and non-indicator variables.
Additionally, there are some indicator variables that are dependent on another independent variable already included. For example, an indicator to show whether the operational units are above or below a certain value. I have been researching this but have not found anything specific on this case and whether this can still be done with linear regression.