AD ALTA
JOURNAL OF INTERDISCIPLINARY RESEARCH
the highest share of seniors employed part-time out of the total
number of seniors. In 2009, 2010 and 2016, the maximum values
exceeded the arithmetic average in the EU. In the Czech
Republic, Hungary and Slovakia, the values increased over the
period analysed. In Poland, the values decreased.
In the next step, we expressed the parameters of the linear trend
of the share of seniors employed part-time out of the total
number of seniors in all four countries of the V4 and we
expressed the coefficient of determination.
Parameter values are in Table 4. Graphical depictions of the
linear trend of the share of seniors employed part-time out of the
total number of seniors from all countries of the Visegrád Group
and in the EU are in Charts 1-5.
Table 4 Estimation of the linear trend parameters of the share of
seniors employed part-time out of the total number of seniors
y=a+bt, t=1, 2, …8
a
b
R
2
(%)
Czech
Republic
2.37464
0.07369
52.89%
Hungary
0.889286
0.024048
37.17%
Poland
2.77786
-0.08619
93.03%
Slovakia
0.564286
0.040714
55.81%
EU 28
2.42714
0.10119
96.44%
Own processing in Statistica
By examining the quality of linear models, we found that in all
linear models the arithmetic average of the residues was zero.
Based on the Shapiro-Wilk test, we did not reject the zero
hypothesis of normal residues distribution. Based on the Durbin-
Watson statistics, it can be concluded that there was a significant
negative autocorrelation of residues in the model for Poland. In
the linear models for Hungary, Slovakia and the EU, the
autocorrelation of residues was insignificant. In the model for
the Czech Republic it was not possible to decide on
autocorrelation. Heteroscedasticity of the residues was not
confirmed in the models.
From the estimation of the linear trend parameters in all four V4
countries we can say that Poland was the only country in which
the share of seniors employed part-time out of the total number
of seniors decreased. The proportion of seniors employed part-
time out of the total number of seniors decreased by about
0.0862% annually. The graphical representation of the linear
trend of the share of seniors employed part-time out of the total
number of seniors in Poland is in Chart 1.
Chart 1 The share of seniors employed part-time out of the total
number of seniors in Poland
y=(2.77786)+(-0.08619)*x
1
2
3
4
5
6
7
8
0
1
2
3
4
5
6
7
8
9
T
1.9
2.0
2.1
2.2
2.3
2.4
2.5
2.6
2.7
2.8
2.9
T
he s
har
e of
s
eni
or
s
em
pl
oy
ed
par
t-
ti
m
e
Own processing in Statistica
The highest regression coefficient of the share of seniors
employed part-time out of the total number of seniors was in the
Czech Republic. The proportion of seniors employed part-time
out of the total number of seniors increased by about 0.0737%
annually. The graphical representation of the linear trend of the
share of seniors employed part-time out of the total number of
seniors in the Czech Republic is in Chart 2.
Chart 2 The share of seniors employed part-time out of the total
number of seniors in the Czech Republic
y=(2.37464)+(0.07369)*x
1
2
3
4
5
6
7
8
0
1
2
3
4
5
6
7
8
9
T
2.3
2.4
2.5
2.6
2.7
2.8
2.9
3.0
3.1
3.2
3.3
T
he s
har
e of
s
eni
or
s
em
pl
oy
e
d par
t-
ti
m
e
Own processing in Statistica
In Hungary, the linear trend was growing. However, the model
had a coefficient of determination with a relatively low value.
Only 37.17% of the total variability was explained by the model.
The graphical representation of the linear trend of the share of
part-time seniors out of the total number of seniors in Hungary is
in Chart 3.
Chart 3 The share of seniors employed part-time out of the total
number of seniors in Hungary
y=(0.889286)+(0.024048)*x
1
2
3
4
5
6
7
8
0
1
2
3
4
5
6
7
8
9
T
0.85
0.90
0.95
1.00
1.05
1.10
1.15
1.20
T
he s
har
e of
s
eni
or
s
em
pl
oy
ed
par
t-
ti
m
e
Own processing in Statistica
In the Slovak Republic, the regression coefficient of the share of
seniors employed part-time out of the total number of seniors
was about 0.0407%. The graphical representation of the share of
seniors employed part-time out of the total number of seniors in
Slovakia is in Chart 4.
Chart 4 The share of seniors employed part-time out of the total
number of seniors in Slovakia
y=(0.564286)+(0.040714)*x
1
2
3
4
5
6
7
8
0
1
2
3
4
5
6
7
8
9
T
0.50
0.55
0.60
0.65
0.70
0.75
0.80
0.85
0.90
0.95
1.00
T
he s
har
e of
s
eni
or
s
em
pl
oy
ed
par
t-
ti
m
e
Own processing in Statistica
The proportion of seniors employed part-time out of the total
number of seniors in the EU increased by about 0.1012%
annually. Thus, if this trend was to be maintained, the share of
seniors employed part-time out of the total number of seniors in
the EU would increase by about 1% over the next 10 years. The
graphical representation of the linear trend of the share of seniors
employed part-time out of the total number of seniors in the EU
is in Chart 5.
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