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. 2006 Feb 20;6:3. doi: 10.1186/1472-6785-6-3

Table 1.

Six families of 1-dimensional dispersal kernels used in this study, together with their characteristics. The mean distance travelled is obtained from δ=+|x|γ(x)dx MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWF0oazcqGH9aqpdaWdXbqaamaaemaabaGaemiEaGhacaGLhWUaayjcSdGae83SdCMaeiikaGIaemiEaGNaeiykaKIaemizaqMaemiEaGhaleaacqGHsislcqGHEisPaeaacqGHRaWkcqGHEisPa0Gaey4kIipaaaa@42AA@. Expression Γ() stands for the Gamma function.

Kernel families Expression Parameters values Weight of the tail Mean distance travelled, δ
Exponential γ1(x)=12αexp(|xα|) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWFZoWzdaWgaaWcbaGaeGymaedabeaakiabcIcaOiabdIha4jabcMcaPiabg2da9maalaaabaGaeGymaedabaGaeGOmaiJae8xSdegaaiGbcwgaLjabcIha4jabcchaWnaabmaabaGaeyOeI0YaaqWaaeaadaWcaaqaaiabdIha4bqaaiab=f7aHbaaaiaawEa7caGLiWoaaiaawIcacaGLPaaaaaa@442C@ α>0 Rapidly varying
Exponential
α
Gaussian γ2(x)=1παexp(x2α2) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWFZoWzdaWgaaWcbaGaeGOmaidabeaakiabcIcaOiabdIha4jabcMcaPiabg2da9maalaaabaGaeGymaedabaWaaOaaaeaacqWFapaCaSqabaGccqWFXoqyaaGagiyzauMaeiiEaGNaeiiCaa3aaeWaaeaacqGHsisldaWcaaqaaiabdIha4naaCaaaleqabaGaeGOmaidaaaGcbaGae8xSde2aaWbaaSqabeaacqaIYaGmaaaaaaGccaGLOaGaayzkaaaaaa@4449@ α>0 Rapidly varying
Thin-tailed
απ MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaadaWcaaqaaGGaciab=f7aHbqaamaakaaabaGae8hWdahaleqaaaaaaaa@3035@
Power-law γ3(x)=a12α(1+|xα|)a MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWFZoWzdaWgaaWcbaGaeG4mamdabeaakiabcIcaOiabdIha4jabcMcaPiabg2da9maalaaabaGaemyyaeMaeyOeI0IaeGymaedabaGaeGOmaiJae8xSdegaamaabmaabaGaeGymaeJaey4kaSYaaqWaaeaadaWcaaqaaiabdIha4bqaaiab=f7aHbaaaiaawEa7caGLiWoaaiaawIcacaGLPaaadaahaaWcbeqaaiabgkHiTiabdggaHbaaaaa@457E@ α>0
a>1
Regularly varying
Fat-tailed
αa2 MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaadaWcaaqaaGGaciab=f7aHbqaaiabdggaHjabgkHiTiabikdaYaaaaaa@318C@
Exponential power γ4(x)=c2αΓ(1/c)exp(|xα|c) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWFZoWzdaWgaaWcbaGaeGinaqdabeaakiabcIcaOiabdIha4jabcMcaPiabg2da9maalaaabaGaem4yamgabaGaeGOmaiJae8xSdeMaeu4KdCKaeiikaGIaeGymaeJaei4la8Iaem4yamMaeiykaKcaaiGbcwgaLjabcIha4jabcchaWnaabmaabaGaeyOeI0YaaqWaaeaadaWcaaqaaiabdIha4bqaaiab=f7aHbaaaiaawEa7caGLiWoadaahaaWcbeqaaiabdogaJbaaaOGaayjkaiaawMcaaaaa@4C56@ α,c>0 Rapidly varying
Thin-tailed for c>1
Fat-tailed for c<1
Exponential for c = 1
αΓ(2/c)Γ(1/c) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWFXoqydaWcaaqaaiabfo5ahjabcIcaOiabikdaYiabc+caViabdogaJjabcMcaPaqaaiabfo5ahjabcIcaOiabigdaXiabc+caViabdogaJjabcMcaPaaaaaa@3AE2@
2Dt γ5(x)=Γ(a)απΓ(a12)(1+x2α2)a MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWFZoWzdaWgaaWcbaGaeGynaudabeaakiabcIcaOiabdIha4jabcMcaPiabg2da9maalaaabaGaeu4KdCKaeiikaGIaemyyaeMaeiykaKcabaGae8xSde2aaOaaaeaacqWFapaCaSqabaGccqqHtoWrdaqadaqaaiabdggaHjabgkHiTmaalaaabaGaeGymaedabaGaeGOmaidaaaGaayjkaiaawMcaaaaadaqadaqaaiabigdaXiabgUcaRmaalaaabaGaemiEaG3aaWbaaSqabeaacqaIYaGmaaaakeaacqWFXoqydaahaaWcbeqaaiabikdaYaaaaaaakiaawIcacaGLPaaadaahaaWcbeqaaiabgkHiTiabdggaHbaaaaa@4DF5@ α>0
a>1/2
Regularly varying
Fat-tailed
απ(a1)Γ(a)Γ(a12) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaadaWcaaqaaGGaciab=f7aHbqaamaakaaabaGae8hWdahaleqaaOGaeiikaGIaemyyaeMaeyOeI0IaeGymaeJaeiykaKcaamaalaaabaGaeu4KdCKaeiikaGIaemyyaeMaeiykaKcabaGaeu4KdC0aaeWaaeaacqWGHbqycqGHsisldaWcaaqaaiabigdaXaqaaiabikdaYaaaaiaawIcacaGLPaaaaaaaaa@40A9@
Mixture of two Gaussians γ6(x)=p(1πα1ex2/α12)+(1p)(1πα2ex2/α22) MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaaiiGacqWFZoWzdaWgaaWcbaGaeGOnaydabeaakiabcIcaOiabdIha4jabcMcaPiabg2da9iabdchaWnaabmaabaWaaSaaaeaacqaIXaqmaeaadaGcaaqaaiab=b8aWbWcbeaakiab=f7aHnaaBaaaleaacqaIXaqmaeqaaaaakiabdwgaLnaaCaaaleqabaWaaSGbaeaacqGHsislcqWG4baEdaahaaadbeqaaiabikdaYaaaaSqaaiab=f7aHnaaDaaameaacqaIXaqmaeaacqaIYaGmaaaaaaaaaOGaayjkaiaawMcaaiabgUcaRmaabmaabaGaeGymaeJaeyOeI0IaemiCaahacaGLOaGaayzkaaWaaeWaaeaadaWcaaqaaiabigdaXaqaamaakaaabaGae8hWdahaleqaaOGae8xSde2aaSbaaSqaaiabikdaYaqabaaaaOGaemyzau2aaWbaaSqabeaadaWcgaqaaiabgkHiTiabdIha4naaCaaameqabaGaeGOmaidaaaWcbaGae8xSde2aa0baaWqaaiabikdaYaqaaiabikdaYaaaaaaaaaGccaGLOaGaayzkaaaaaa@5ADB@ α1α2
p>0
Rapidly varying
Thin-tailed (but leptokurtic)
pα1π+(1p)α2π MathType@MTEF@5@5@+=feaafiart1ev1aaatCvAUfKttLearuWrP9MDH5MBPbIqV92AaeXatLxBI9gBaebbnrfifHhDYfgasaacH8akY=wiFfYdH8Gipec8Eeeu0xXdbba9frFj0=OqFfea0dXdd9vqai=hGuQ8kuc9pgc9s8qqaq=dirpe0xb9q8qiLsFr0=vr0=vr0dc8meaabaqaciaacaGaaeqabaqabeGadaaakeaacqWGWbaCdaWcaaqaaGGaciab=f7aHnaaBaaaleaacqaIXaqmaeqaaaGcbaWaaOaaaeaacqWFapaCaSqabaaaaOGaey4kaSYaaeWaaeaacqaIXaqmcqGHsislcqWGWbaCaiaawIcacaGLPaaadaWcaaqaaiab=f7aHnaaBaaaleaacqaIYaGmaeqaaaGcbaWaaOaaaeaacqWFapaCaSqabaaaaaaa@3D24@