<s>
Empirical	B-General_Concept
software	I-General_Concept
engineering	I-General_Concept
(	O
ESE	O
)	O
is	O
a	O
subfield	O
of	O
software	B-General_Concept
engineering	I-General_Concept
(	O
SE	O
)	O
research	O
that	O
uses	O
empirical	O
research	O
methods	O
to	O
study	O
and	O
evaluate	O
an	O
SE	O
phenomenon	O
of	O
interest	O
.	O
</s>
<s>
ESE	O
has	O
roots	O
in	O
experimental	O
software	B-General_Concept
engineering	I-General_Concept
,	O
but	O
as	O
the	O
field	O
has	O
matured	O
the	O
need	O
and	O
acceptance	O
for	O
both	O
quantitative	O
and	O
qualitative	O
research	O
has	O
grown	O
.	O
</s>
