Computational Evolutionary Biology & Bioinformatics

E-mail: msr@asu.edu
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## history *h-*index

### Example

### History

## References

The history *h-*index (Randić 2009) is another metric designed to help distinguish among researchers with identical *h-*indices. It is based on the idea of exploring a power expansion of the citation counts for publications in the core. This index starts by creating a vector representing larger power expansions of citation counts. The *k*^{th} element of the vector is the largest rank (*i*), for which the number of citations for that publication is equal or larger than the rank times 2^{k}, or

By definition, the first (zeroth) entry is *h* (since 2^{0} = 1). Graphically, this is looking at the intersection (rounding the rank down to the nearest integer) of the citation curve with a series of lines with ever increasing slopes of 2^{k}: 1 (=*h*), 2, 4, 8, etc., with the largest *k* equal to the line with the largest slope that actually intersects the citation curve.

The history *h-*index is simply the sum of the values in this vector, or

where *K* is the largest power of 2 for which *C*_{max} >= 2^{K}.

Publications are ordered by number of citations, from highest to lowest.

Citations (C)_{i} | Rank (i) | 2^{0} | 2^{1} | 2^{2} | 2^{3} | 2^{4} | 2^{5} | 2^{6} | |
---|---|---|---|---|---|---|---|---|---|

H^{5} = 1 | 42 | 1 | 1 | 2 | 4 | 8 | 16 | 32 | 64 |

H^{3} = 2, H^{4} = 2 | 36 | 2 | 2 | 4 | 8 | 16 | 32 | 64 | 128 |

H^{2} = 3 | 14 | 3 | 3 | 6 | 12 | 24 | 48 | 96 | 192 |

H^{1} = 4 | 11 | 4 | 4 | 8 | 16 | 32 | 64 | 128 | 256 |

9 | 5 | 5 | 10 | 20 | 40 | 80 | 160 | 320 | |

H^{0} = 6 | 9 | 6 | 6 | 12 | 24 | 48 | 96 | 192 | 384 |

3 | 7 | 7 | 14 | 28 | 56 | 112 | 224 | 448 | |

2 | 8 | 8 | 16 | 32 | 64 | 128 | 256 | 512 | |

2 | 9 | 9 | 18 | 36 | 72 | 144 | 288 | 576 | |

2 | 10 | 10 | 20 | 40 | 80 | 160 | 320 | 640 | |

1 | 11 | 11 | 22 | 44 | 88 | 176 | 352 | 704 | |

1 | 12 | 12 | 24 | 48 | 96 | 192 | 384 | 768 | |

1 | 13 | 13 | 26 | 52 | 104 | 208 | 416 | 832 | |

0 | 14 | 14 | 28 | 56 | 112 | 224 | 448 | 896 | |

0 | 15 | 15 | 30 | 60 | 120 | 240 | 480 | 960 | |

0 | 16 | 16 | 32 | 64 | 128 | 256 | 512 | 1024 |

The sum of all of the *H ^{k}* values is 18.

Year | H |
---|---|

1997 | 1 |

1998 | 4 |

1999 | 9 |

2000 | 13 |

2001 | 18 |

2002 | 22 |

2003 | 27 |

2004 | 34 |

2005 | 44 |

2006 | 50 |

2007 | 56 |

2008 | 66 |

2009 | 74 |

2010 | 78 |

2011 | 83 |

2012 | 91 |

2013 | 98 |

2014 | 106 |

2015 | 112 |

2016 | 117 |

2017 | 117 |

- Randić, M. (2009) Citations versus limitations of citations: Beyond Hirsch index.
*Scientometrics*80(3):809–818.