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From |
Yuval Arbel <yuval.arbel@gmail.com> |

To |
statalist@hsphsun2.harvard.edu |

Subject |
Re: st: How to generate an index for the calculation of geometric mean |

Date |
Tue, 11 Dec 2012 11:57:23 +0200 |

It's not 2.3 but rather t=1 for reduct_per==25, t=2 for reduct_per==625, t=3 for reduct_per==15625 etc, so that when I calculate 625^(1/2) and 15625^(1/3) I get 25 On Tue, Dec 11, 2012 at 11:46 AM, Nick Cox <njcoxstata@gmail.com> wrote: > I didn't understand what you want when you asked this yesterday, and > the same applies to this repetition. Specifically, where does the 2.3 > come from? Please show the formula which produces this result. > > Nick > > On Tue, Dec 11, 2012 at 7:31 AM, Yuval Arbel <yuval.arbel@gmail.com> wrote: > >> I would like to generate an index variable for the calculation of the >> geometrical mean of an unbalanced panel (namely, the exponent, which >> makes the product a >> geometrical mean). >> >> Here is an example of one panel: >> >> . list reduct_per y3 if appt==2862 >> >> +---------------------+ >> | reduct~r y3 | >> |---------------------| >> 30. | 1 1 | >> 31. | 1 1 | >> 32. | 1 1 | >> 33. | 1 1 | >> 34. | 1 1 | >> |---------------------| >> 35. | 1 1 | >> 36. | 1 1 | >> 37. | 1 1 | >> 38. | 1 1 | >> 39. | 1 1 | >> |---------------------| >> 40. | 1 1 | >> 41. | 1 1 | >> 42. | 1 1 | >> 43. | 1 1 | >> 44. | 1 1 | >> |---------------------| >> 45. | 1 1 | >> 46. | 1 1 | >> 47. | 1 1 | >> 48. | 1 1 | >> 49. | 1 1 | >> |---------------------| >> 50. | 1 1 | >> 51. | 1 1 | >> 52. | 1 1 | >> 53. | 1 1 | >> 54. | 1 1 | >> |---------------------| >> 55. | 25 25 | >> 56. | 25 625 | >> 57. | 25 15625 | >> 58. | 25 390625 | >> 59. | 25 9765625 | >> |---------------------| >> 60. | 25 2.44e+08 | >> 61. | 25 6.10e+09 | >> 62. | 25 1.53e+11 | >> 63. | 25 3.81e+12 | >> 64. | 25 9.54e+13 | >> |---------------------| >> 65. | 25 2.38e+15 | >> 66. | 25 5.96e+16 | >> +---------------------+ >> >> >> The problem is that for reduct_per==1 I would like >> the index to become a constant and remain the same until the next >> reduct_per, which is different from zero, comes. >> >> Consider the example above: during the first 26 periods the index >> should be one and and starting from the 26th period it should change >> to 2,3 etc. >> >> If, on the other hand, we would have opposite descending trail (namely >> 25 percent reduction rate from 1-25 and zero starting from the 26th >> period), the index should be 1, 2,..,25 and then becomes a constant 25 from >> the 26th period. >> >> What is the simplest way to generate such an index? Can it be done >> without a loop? > * > * For searches and help try: > * http://www.stata.com/help.cgi?search > * http://www.stata.com/support/faqs/resources/statalist-faq/ > * http://www.ats.ucla.edu/stat/stata/ -- Dr. Yuval Arbel School of Business Carmel Academic Center 4 Shaar Palmer Street, Haifa 33031, Israel e-mail1: yuval.arbel@carmel.ac.il e-mail2: yuval.arbel@gmail.com * * For searches and help try: * http://www.stata.com/help.cgi?search * http://www.stata.com/support/faqs/resources/statalist-faq/ * http://www.ats.ucla.edu/stat/stata/

**Follow-Ups**:**Re: st: How to generate an index for the calculation of geometric mean***From:*Nick Cox <njcoxstata@gmail.com>

**References**:**st: How to generate an index for the calculation of geometric mean***From:*Yuval Arbel <yuval.arbel@gmail.com>

**Re: st: How to generate an index for the calculation of geometric mean***From:*Nick Cox <njcoxstata@gmail.com>

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