For this week is very useful and interesting because we are all living with this.
According the video, The woman was sitting, on her table have a phone and speaker.
So if her speaker are playing the music like this (あいうえお〜〜〜)
and her phone's ring tone is like this (AIUEO〜〜)
It could be ending in 4 possibilities
1. HIT : positive response when there is a signal = the phone is ringing and she picks up the phone (ringtone = signal, speaker music = noise).
2. MISS : negative response when there is a signal = the phone is ringing and she doesn't pick up. (she miss the signal (ringtone))
3. False alarm : positive response when there is no signal = the phone doesn't ring but she check/pick the phone up.
4. Correct rejection : negative response when there is no signal = the phone doesn't ring and she doesn't pick up the phone.
D' (D prime)
In this case = speaker are playing(あいうえお〜〜)the same sound of ringtone(あいうえお〜〜).