<s>
In	O
computer	B-General_Concept
science	I-General_Concept
,	O
programming	B-Application
by	I-Application
demonstration	I-Application
(	O
PbD	O
)	O
is	O
an	O
end-user	O
development	O
technique	O
for	O
teaching	O
a	O
computer	O
or	O
a	O
robot	O
new	O
behaviors	O
by	O
demonstrating	O
the	O
task	O
to	O
transfer	O
directly	O
instead	O
of	O
programming	O
it	O
through	O
machine	O
commands	O
.	O
</s>
<s>
The	O
terms	O
programming	B-Application
by	I-Application
example	I-Application
(	O
PbE	O
)	O
and	O
programming	B-Application
by	I-Application
demonstration	I-Application
(	O
PbD	O
)	O
appeared	O
in	O
software	O
development	O
research	O
as	O
early	O
as	O
the	O
mid	O
1980s	O
to	O
define	O
a	O
way	O
to	O
define	O
a	O
sequence	O
of	O
operations	O
without	O
having	O
to	O
learn	O
a	O
programming	O
language	O
.	O
</s>
<s>
The	O
usual	O
distinction	O
in	O
literature	O
between	O
these	O
terms	O
is	O
that	O
in	O
PbE	O
the	O
user	O
gives	O
a	O
prototypical	O
product	O
of	O
the	O
computer	O
execution	O
,	O
such	O
as	O
a	B-Application
row	I-Application
in	I-Application
the	I-Application
desired	I-Application
results	I-Application
of	I-Application
a	I-Application
query	I-Application
;	O
while	O
in	O
PbD	O
the	O
user	O
performs	O
a	O
sequence	O
of	O
actions	O
that	O
the	O
computer	O
must	O
repeat	O
,	O
generalizing	O
it	O
to	O
be	O
used	O
in	O
different	O
data	O
sets	O
.	O
</s>
<s>
This	O
framework	O
can	O
be	O
contrasted	O
with	O
Bayesian	B-Application
program	I-Application
synthesis	I-Application
.	O
</s>
<s>
proposed	O
to	O
resolve	O
the	O
generalization	O
issue	O
,	O
basically	O
dichotomized	O
in	O
learning	O
methods	O
at	O
a	O
symbolic	O
level	O
or	O
at	O
a	O
trajectory	B-Application
level	O
.	O
</s>
<s>
The	O
development	O
of	O
humanoid	O
robots	O
naturally	O
brought	O
a	O
growing	O
interest	O
in	O
robot	B-Application
programming	I-Application
by	I-Application
demonstration	I-Application
.	O
</s>
<s>
With	O
the	O
increasing	O
consideration	O
of	O
this	O
body	O
of	O
work	O
in	O
robotics	O
,	O
the	O
notion	O
of	O
Robot	B-Application
programming	I-Application
by	I-Application
demonstration	I-Application
(	O
also	O
known	O
as	O
RPD	O
or	O
RbD	O
)	O
was	O
also	O
progressively	O
replaced	O
by	O
the	O
more	O
biological	O
label	O
of	O
Learning	O
by	O
imitation	O
.	O
</s>
<s>
Neurally-imprinted	O
Stable	O
Vector	O
Fields	O
(	O
NiVF	O
)	O
was	O
introduced	O
as	O
a	O
novel	O
learning	O
scheme	O
during	O
ESANN	O
2013	O
and	O
show	O
how	O
to	O
imprint	O
vector	O
fields	O
into	O
neurals	O
networks	O
such	O
as	O
Extreme	B-Algorithm
Learning	I-Algorithm
Machines	I-Algorithm
(	O
ELMs	O
)	O
in	O
a	O
guaranteed	O
stable	O
manner	O
.	O
</s>
<s>
The	O
networks	O
represent	O
movements	O
,	O
where	O
asymptotic	O
stability	O
is	O
incorporated	O
through	O
constraints	B-Application
derived	O
from	O
Lyapunov	O
stability	O
theory	O
.	O
</s>
<s>
Second	O
,	O
stability	O
is	O
incorporated	O
by	O
means	O
of	O
a	O
novel	O
method	O
to	O
respect	O
local	O
constraints	B-Application
in	O
the	O
neural	O
learning	O
.	O
</s>
<s>
After	O
a	O
task	O
was	O
demonstrated	O
by	O
a	O
human	O
operator	O
,	O
the	O
trajectory	B-Application
is	O
stored	O
in	O
a	O
database	O
.	O
</s>
<s>
A	O
skill	O
is	O
requesting	O
a	O
database	O
and	O
generates	O
a	O
trajectory	B-Application
.	O
</s>
<s>
The	O
parameters	O
of	O
a	O
skill	O
allow	O
to	O
modify	O
the	O
policy	O
to	O
fulfill	O
external	O
constraints	B-Application
.	O
</s>
<s>
They	O
generate	O
a	O
robot	O
trajectory	B-Application
on	O
the	O
fly	O
which	O
was	O
unknown	O
at	O
the	O
time	O
of	O
the	O
demonstration	O
.	O
</s>
<s>
Photoshop	B-Operating_System
)	O
,	O
the	O
most	O
simple	O
case	O
of	O
PbD	O
is	O
the	O
macro	B-Application
recorder	I-Application
.	O
</s>
