The circular regression model may contain one or more data points which appear to be peculiar or inconsistent with the main part of the model. This may be occur due to recording errors, sudden short events, sampling under abnormal conditions etc. The existence of these data points “outliers” in the data set cause lot of problems in the research results and the conclusions. Therefore, we should identify them before applying statistical analysis. In this article, we aim to propose a statistic to identify outliers in the both of the response and explanatory variables of the simple circular regression model. Our proposed statistic is robust circular distance RCDxy and it is justified by the three robust measurements such as proportion of detection outliers, masking and swamping rates.

1.
A.L.
Gould
, “
A Regression Technique for Angular Varieties
Biometrics
, Vol.
25
, No. (
4
), pp.
683
700
,
1969
.
2.
K. V.
Mardia
,
Statistics of Directional Data
Academic Press
,
London
,
1972
.
3.
S. R.
Jammalamadaka
, and
Y. R.
Sarma
,
Stat. Sci. Data Analy.
, In :
Matsusita
,
K.
, ed..
Utrecht
:
VSP
. pp.
109
128
(
1993
).
4.
A. G.
Hussin
,
N. R. J.
Fieller
and
E. C.
Stillman
,
J. Appl. Sci. Technol.
8
(
1-2
),
1
6
(
2004
).
5.
K. V.
Mardia
, and
P.
Jupp
,
Directional Statistics
(
Wiley
,
London
,
2000
).
6.
A. G.
Hussin
,
A. H.
Abuzaid
, and
I.
Mohamed
,
proceedings of the International Conference on Nonparametric Methods for Measurement Error Models and Related Topics
,
Ottawa, Canada
, pp.
3
5
(
2009
).
7.
S. F.
Hassan
,
A. G.
Hussin
, and
Y. Z.
Zubairi
,
Chiang Mai J. Sci.
37
(
2
),
195
205
(
2010
).
8.
Nikolai
Chernov
,
Circular and Linear Regression Fitting Circles and Lines by Least Squares
(
Taylor and Francis Group
,
USA
,
2011
).
9.
A.
Rambli
, “
Outlier Detection in Circular Data and Circular – Circular Regression Model
,” Master Thesis,
University of Malay
,
2011
.
10.
A. H.
Abuzaid
,
A. G.
Hussin
and
I. B.
Mohamed
.
J. Stat. Comp. Simula.
83
(
2
),
269
277
(
2013
).
11.
A. G.
Hussin
,
A. H.
Abuzaid
,
A. I. N.
Ibrahim
, and
A.
Rambli
,
Sci. Mal.
42
(
6
),
869
874
(
2013
).
12.
R.A.
Maronna
,
R.D.
Martin
, and
V.J.
Yohai
,
Robust Statistics-Theory and Methods
(
John Wiley & Sons Ltd.
,
2006
).
13.
P.J.
Rousseeuw
, and
A.
Leroy
,
Robust Regression and Outlier Detection
(
New York
.:
Wiley
,
1987
).
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