Help, I am a desperate student, totally beginner here and I am rather slow with logic.
I need to generate the Cronbach's Alpha, using pt60 file, and need to interpret the result. Prior to this, I was asked to select the data and mutate missing values into NA; I ran it no problemo...until generating it to Mr. Cron's alpha then it shows error unknown color. I suppose it is because Mr.Cron likes numeric formatting and NA is not numeric. I tried my best but still cannot change Mr. Cron's heart into non numeric Mademoiselle. 
my script were:
library(psych)
pt60 |> select(BY_R610, BY_R609, BY_R608, BY_R605, BY_R601) |> map(max)
str(pt60_selected)
pt60_selected_numeric <- na.omit(pt60_selected_numeric)
alpha(pt60_selected)
and console shows:
