How to fix 'variable lengths differ' error?

Question

This is my code:

Income.x1 <- ifelse(Income ==1, "L", ifelse(Income == 2, "M",ifelse(Income == 3, "H",NA)))
gender.x2 <- ifelse(Gender==1, "M",ifelse(Gender == 2, "F",NA))
Happy.x3 <- ifelse(Happy==1,"A",ifelse(Happy==2,"B",ifelse(Happy==3,"C",NA)))

regr.x = lm(TVhours ~ Income.x1 + Happy.x3+ gender.x2)
sRegr.5 = summary(regr.x);sRegr.5

This is my error:

Error in model.frame.default(formula = TVhours ~ Income.x1 + Happy.x3 + : variable lengths differ (found for 'gender.x2')

why is there a variable length issue?

Answer 1

You probably just have more (less) observations in one variable, check the length of every variable involved in your linear regression model. See how I can get the same error with:

x1 <- c(1,2,3,4)
x2 <- c(1,2,3,4,5)

length(x1)
length(x2)

lm(x1~x2)

Console output:

Error in model.frame.default(formula = x1 ~ x2, drop.unused.levels = TRUE) : 
  variable lengths differ (found for 'x2')