<s>
In	O
statistics	O
,	O
a	O
mixed-design	B-General_Concept
analysis	I-General_Concept
of	I-General_Concept
variance	I-General_Concept
model	O
,	O
also	O
known	O
as	O
a	O
split-plot	B-General_Concept
ANOVA	B-General_Concept
,	O
is	O
used	O
to	O
test	O
for	O
differences	O
between	O
two	O
or	O
more	O
independent	O
groups	O
whilst	O
subjecting	O
participants	O
to	O
repeated	O
measures	O
.	O
</s>
<s>
Thus	O
,	O
in	O
a	O
mixed-design	B-General_Concept
ANOVA	I-General_Concept
model	O
,	O
one	O
factor	O
(	O
a	O
fixed	B-General_Concept
effects	I-General_Concept
factor	I-General_Concept
)	O
is	O
a	O
between-subjects	O
variable	O
and	O
the	O
other	O
(	O
a	O
random	B-General_Concept
effects	I-General_Concept
factor	I-General_Concept
)	O
is	O
a	O
within-subjects	O
variable	O
.	O
</s>
<s>
Thus	O
,	O
overall	O
,	O
the	O
model	O
is	O
a	O
type	O
of	O
mixed-effects	B-General_Concept
model	I-General_Concept
.	O
</s>
<s>
Andy	O
Field	O
(	O
2009	O
)	O
provided	O
an	O
example	O
of	O
a	O
mixed-design	B-General_Concept
ANOVA	I-General_Concept
in	O
which	O
he	O
wants	O
to	O
investigate	O
whether	O
personality	O
or	O
attractiveness	O
is	O
the	O
most	O
important	O
quality	O
for	O
individuals	O
seeking	O
a	O
partner	O
.	O
</s>
<s>
When	O
running	O
an	O
analysis	B-General_Concept
of	I-General_Concept
variance	I-General_Concept
to	O
analyse	O
a	O
data	O
set	O
,	O
the	O
data	O
set	O
should	O
meet	O
the	O
following	O
criteria	O
:	O
</s>
<s>
For	O
the	O
between-subject	O
effects	O
to	O
meet	O
the	O
assumptions	O
of	O
the	O
analysis	B-General_Concept
of	I-General_Concept
variance	I-General_Concept
,	O
the	O
variance	O
for	O
any	O
level	O
of	O
a	O
group	O
must	O
be	O
the	O
same	O
as	O
the	O
variance	O
for	O
the	O
mean	O
of	O
all	O
other	O
levels	O
of	O
the	O
group	O
.	O
</s>
<s>
Due	O
to	O
the	O
fact	O
that	O
the	O
mixed-design	B-General_Concept
ANOVA	I-General_Concept
uses	O
both	O
between-subject	O
variables	O
and	O
within-subject	O
variables	O
(	O
a.k.a.	O
</s>
<s>
More	O
specifically	O
,	O
the	O
total	O
sum	O
of	O
squares	O
in	O
a	O
regular	O
one-way	O
ANOVA	B-General_Concept
would	O
consist	O
of	O
two	O
parts	O
:	O
variance	O
due	O
to	O
treatment	O
or	O
condition	O
(	O
SSbetween-subjects	O
)	O
and	O
variance	O
due	O
to	O
error	O
(	O
SSwithin-subjects	O
)	O
.	O
</s>
<s>
When	O
following	O
up	O
interactions	O
for	O
terms	O
that	O
are	O
both	O
between-subjects	O
or	O
both	O
within-subjects	O
variables	O
,	O
the	O
method	O
is	O
identical	O
to	O
follow-up	O
tests	O
in	O
ANOVA	B-General_Concept
.	O
</s>
<s>
See	O
ANOVA	B-General_Concept
.	O
</s>
