One of the assumptions for Spearman correlation is that there is a monotonic relationship between the two variables. I've created a scatterplot for two Likert item variables, but it seems impossible to get the desired monotonic plot. Must the monotonicity assumption be met for me to calculate the Spearman correlation?
My second question is, can I correlate respondent's score (scale) with a Likert item or any one variable that is nominal. In this case should I rank the score first in SPSS by creating a new column for rank score or will SPSS do it for me?