Most of the Alfred editions of piano music, including Bartok, make an effort to write an analysis of the music and provide information about performance practice. The preface to Bartok's Allegro Barbara says this: "- is the weakest possible accent and is played with a non-legato touch in which the gap between the two tones is hardly perceptible (the key is pressed rather than struck)> is a weak accent^ is a medium strong accentsf is a strong accentsff is the strongest possible accent"The important thing is to distinguish between them in your playing. The exact quality of each will depend on the piano and pianist.
Topic: Bartok's emphasis differences 