In this study, we perform a statistical investigation of the kinematic classification of 4,264 coronal mass ejections (CMEs) from 1996 to 2015 observed by SOHO/LASCO C3. Using the constant acceleration model, we classify these CMEs into three groups: deceleration, constant velocity, and acceleration motion. For this, we devise three different classification methods using fractional speed variation, height contribution, and visual inspection. The main results of this study can be summarized as follows. First, the fractions of three groups depend on the method used. Second, about half of the events belong to the groups of acceleration and deceleration. Third, the fractions of three motion groups as a function of CME speed are consistent with one another. Fourth, the fraction of acceleration motion decreases as CME speed increases, while the fractions of other motions increase with speed. In addition, the acceleration motions are dominant in low speed CMEs whereas the constant velocity motions are dominant in high speed CMEs.

Abstract
1. INTRODUCTION
2. DATA
3. CLASSIFICATION METHOD
    3.1. Classification by Fractional Speed Variation
    3.2. Classification by Height Contribution
    3.3. Classification by Visual Inspection
4. RESULT AND DISCUSSION
    4.1. Three Distinct Types of CME Kinematic Motions
    4.2. Fraction of Three Types of CME MotionsDepending on Their Speeds
    4.3. Fractions of Three Types of CME MotionsDepending on Solar Cycle Phase
5. SUMMARY AND CONCLUSION
ACKNOWLEDGMENTS
REFERENCES

• Seong-Gyeong Jeon(School of Space Research, Kyung Hee University)
• Yong-Jae Moon(School of Space Research, Kyung Hee University,Department of Astronomy & Space Science, Kyung Hee University) Corresponding Author
• Il-Hyun Cho(Department of Astronomy & Space Science, Kyung Hee University)
• Harim Lee(Department of Astronomy & Space Science, Kyung Hee University)
• Kangwoo Yi(Department of Astronomy & Space Science, Kyung Hee University)