Arules returning empty LHS

Question

I have a dataset which looks like this:

\"user.get\",\"search_restaurants\",\"cuisines.get\"
\"user.get\",\"search_restaurants\",\"user.get\",\"search_restaurant         


        

Answer 1

The answer by luke is correct. In addition, we can say that apriori always gives us information about the consequent which is RHS in the program. That's why for a single item set having min support equal to min confidence is also given in the resulting output if no 'minlen' is used.

Eg.

  > inspect(rules)
    lhs            rhs     support confidence lift count
[1] {}          => {Soup}  0.8     0.8        1.0  4    
[2] {}          => {Pasta} 0.8     0.8        1.0  4    
[3] {Salad}     => {Ham}   0.4     1.0        1.7  2 

I hope this explains the output(other rules are not shown in this example). The above given is the partial output of this table.

Customer ID       Food 
 1          -Salad, Hamburger, Taco  
 2          -Soup, Hamburger, Pasta 
 3          -Salad, Soup, Hamburger, Pasta 
 4          -Soup, Pasta 
 5          -Taco, Pasta, Soup