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STS426 Tanuka C.
classified the galaxies into homogeneous groups and then we have studied
the star formation properties of those groups separately.
In the present work we have classified the data set of nearby galaxies using
GMMBC on the basis of star formation related variables and discussed the
groups in terms of their SFr properties.
The rest of this paper is organized into four further sections. Section 2
delineates the data set used and its features and importance for inclusion in
our study. Overview and relevant discussions on the statistical methodology
used are discussed in Section 3. Section 4 is based on the analyses and
interpretations. Finally, the paper concludes with some discussions and
provisions for further research pertaining to this area.

2. Overview of The Dataset
We have prepared a suitable dataset of nearby galaxies from an original
dataset compiled by ?. Primarily we concentrated on the absolute magnitudes
and the parameters associated with the star formation rates e.g., mass of the
̃
neutral hydrogen (MHI) etc. In the dataset we have computed of the
galaxies following ? which is more robust (?) given by,

̃
log (( −1 )) = 2.78 − 0.4 + 2 (1)
⊙
and

= − 1.93( + ) (2)

where, D is the distance of a galaxy, is the Far-Ultra-Violet apparent

magnitude corrected for extinction and , are galactic extinction in B-

band (?) and internal extinction in galaxies in B-band (?) respectively.
We have considered the variables associated with the star formation
history, e. g.,
(i) Axial ratio (/) measured at the Holmberg isophote,
(ii) Absolute magnitudes in K, B bands ( , ) and in HI line ( ),
21

(iii) Logarithm of Mass of the neutral hydrogen (log(MHI)),
(iv) Holmberg radius ( ),
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(v) Tidal index (1),
(vi) Surface brightness (SBB) in B-band within Holm-berg radius, and
(vii) Neutral hydrogen mass to K band luminosity ratio (/ ),

for primary statistical analyses along with () (mentioned above and
also others) for subsequent comparison.
After several boxplots of the above parameters together with the
computation of standard errors we have finally selected the complete data of
596 samples. The remaining parameters which have a considerable amount of
missing values and morphological indices (estimated in a subjective way) have
not been considered for statistical analyses are: Radial velocity of the galaxy

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