what is the r factor level which factor is used in a regression equation and which should not be used how does factor level of regression work what factor level should be used as regressor in r when factor level is used as regressor variable which factor level should be used as regressor variables in r? how can factor levels be automatically chosen in r why a factor is used as a regressor? if a factor is positive in a regression model, what is the positive mean why should a factor be chosen in regression what is an example of a factor-level in r? how can factor levels be manually chosen in r? r how to find factors does r automatically select the negative coefficient which factor-level should be used as a regressor variable in r what are factor levels used for how do factor level in r work in regression what level of factor is used as a regressor which variables in regression have negative coefficients? which factor is used in the regression process