parameter

Hello All 

im new to ssrs so please bear with me 

i have a report that shows me 5 fields 

JobNo   company    jobtype      placedid 

j1234TEST           Perm      112345 (placed)

j1567test1           perm      76543   (placed)

J9876      test2                      perm                            (not placed no id)

i have tried to add a parameter which lets me select all placed (i.e all with a placeid) all not placed(no id) and all jobs which will contain both i have managed to get a Boolean selection that lets me select either all or placed but not not placed

i was hoping to set this as below

parameter 

as an integer with available fields

Label                    value

Placed                  >1

not placed           <1

all null 

but not sure how i can do this as you cant use the >< integer 

any ideas please!!! 

much appreciated