Chapter 1 Datasets in stelfi

Below are the data packaged within stelfi.

##       Item             Title                                                  
##  [1,] "horse_mesh"     "Example Delaunay triangulation"                       
##  [2,] "horse_sf"       "Example 'sf' 'POLYGON'"                               
##  [3,] "iraq_terrorism" "Terrorism in Iraq, 2013 - 2017"                       
##  [4,] "marked"         "Example marked point pattern data set"                
##  [5,] "nz_earthquakes" "Earthquakes in Canterbury, NZ, 2010 - 2014"           
##  [6,] "nz_murders"     "Murders of NZ, 2004 - 2019"                           
##  [7,] "retweets_niwa"  "Retweets of NIWA's viral leopard seal Tweet"          
##  [8,] "sasquatch"      "Sasquatch (bigfoot) sightings in the USA, 2000 - 2005"
##  [9,] "uk_serial"      "Serial killers of the UK, 1828 - 2015"                
## [10,] "xyt"            "Self-exciting point pattern"

1.1 Temporal point pattern data

retweets_niwa

In 2019 a NIWA scientist found a working USB in the scat of a leopard seal, they then tweeted about it in the hopes of finding its owner. In this chapter a Hawkes process is fitted to these data.

The retweets_niwa dataset contains the retweet timestamps for this tweet.

## [1] "2019-02-07 06:50:08 UTC" "2019-02-07 06:50:08 UTC"
## [3] "2019-02-07 06:49:22 UTC" "2019-02-07 06:48:48 UTC"
## [5] "2019-02-07 06:47:52 UTC" "2019-02-07 06:47:42 UTC"

uk_serial

Murder UK documents some of the UKs most infamous multiple murderer cases. The uk_serial dataset contains summary information about the documented cases along with approximate timeframes.

##   number_of_kills       years                           name                aka
## 1             300 1995 - 1998             Dr. Harold Shipman          Dr. Death
## 2             160 1949 - 1983          Dr. John Bodkin Adams                   
## 3              26        1978                 Peter Dinsdale          Bruce Lee
## 4              21 1865 - 1872                Mary Ann Cotton                   
## 5              16        1828 William Burke and William Hare     Body Snatchers
## 6              15 1944 - 1948              John George Haigh Acid Bath Murderer
##   year_start year_end date_of_first_kill population_million
## 1       1995     1998            03/1995              58.02
## 2       1949     1983            08/1949              50.32
## 3       1973       NA            06/1973              56.19
## 4       1865     1872            01/1865              24.36
## 5       1828       NA            02/1828              15.73
## 6       1944     1948            09/1944              49.02

1.2 Spatiotemporal point pattern data

Using maps to create sf objects of country boundaries:

sasquatch

The Bigfoot Field Researchers Organization (BFRO) documents Bigfoot (Sasquatch) sightings; some data have been collated and packaged in stelfi assasquatch.

## Simple feature collection with 972 features and 27 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: -124.5301 ymin: 25.84875 xmax: -70.75587 ymax: 48.9058
## CRS:           +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0
## # A tibble: 972 × 28
##    observed  locat…¹ county state season title date       number class…² geohash
##  * <chr>     <chr>   <chr>  <chr> <chr>  <chr> <date>      <dbl> <chr>   <chr>  
##  1 "For the… This l… Shann… Sout… Fall   Repo… 2002-12-04   5173 Class A 9xxntv…
##  2 "My fami… East o… Wayne… New … Fall   Repo… 2003-09-20  26566 Class A dr9q4m…
##  3 "While t… Ward C… Ward … Nort… Spring Repo… 2000-04-21    751 Class A c8xfw2…
##  4 "(Please… <NA>    Mount… Nort… Winter Repo… 2004-02-22   8165 Class A c8qzwb…
##  5 "I was c… forest… Warre… New … Summer Repo… 2005-12-21  13276 Class B dr4xfu…
##  6 "My summ… We wer… Taos … New … Spring Repo… 2000-05-17   4904 Class B 9wt01q…
##  7 "On Aug … From G… McLea… Nort… Summer Repo… 2005-08-27  12562 Class A c8rx3m…
##  8 "Foot pr… The lo… McKen… Nort… Winter Repo… 2004-02-26   8130 Class B c8qyyr…
##  9 "The fol… Georgi… Sarpy… Nebr… Summer Repo… 2005-01-06   7809 Class A 9z7f40…
## 10 "We live… (Locat… Dougl… Nebr… Summer Repo… 2005-08-13  12482 Class A 9z7f97…
## # … with 962 more rows, 18 more variables: temperature_high <dbl>,
## #   temperature_mid <dbl>, temperature_low <dbl>, dew_point <dbl>,
## #   humidity <dbl>, cloud_cover <dbl>, moon_phase <dbl>,
## #   precip_intensity <dbl>, precip_probability <dbl>, precip_type <chr>,
## #   pressure <dbl>, summary <chr>, uv_index <dbl>, visibility <dbl>,
## #   wind_bearing <dbl>, wind_speed <dbl>, year <dbl>, geometry <POINT [m]>, and
## #   abbreviated variable names ¹​location_details, ²​classification

nz_earthquakes

GeoNet Quake Search catalogues New Zealand earthquake occurrence; some of these data have been and packaged in stelfi as nz_earthquakes. In this chapter a Hawkes process is fitted to these data.

## Simple feature collection with 3824 features and 3 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 169.83 ymin: -44.86892 xmax: 175.6328 ymax: -41.8628
## CRS:           +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0
## First 10 features:
##             origintime magnitude     depth                   geometry
## 1  2014-12-24 07:46:00  3.208996 13.671875 POINT (172.7133 -43.57944)
## 2  2014-12-24 06:43:00  4.109075  5.820312 POINT (172.7204 -43.55752)
## 3  2014-12-14 08:53:00  3.240377  5.058594 POINT (172.3641 -43.62563)
## 4  2014-12-12 13:37:00  4.459034  9.394531  POINT (172.368 -43.63492)
## 5  2014-11-20 08:24:00  3.116447 10.039062 POINT (172.7836 -43.42493)
## 6  2014-11-18 14:19:00  3.158710 11.269531  POINT (172.7936 -43.4897)
## 7  2014-11-02 06:45:00  3.708697 14.960938 POINT (170.2523 -44.48656)
## 8  2014-10-11 22:32:00  3.456145 39.804688 POINT (173.1383 -42.67562)
## 9  2014-10-01 20:58:00  3.106894 11.386719 POINT (172.6879 -43.49002)
## 10 2014-09-30 15:29:00  3.911931  9.335938 POINT (172.1428 -43.25048)

nz_murders

The Homicide Report documents homicides in New Zealand. The nz_murders dataset contains summary information about the documented cases. In this chapter a spatiotemporal self-exciting model is fitted to these data.

## Simple feature collection with 967 features and 11 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 167.9161 ymin: -46.96127 xmax: 178.3955 ymax: -34.54022
## CRS:           +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0
## First 10 features:
##       sex age   date year                      cause              killer
## 1    Male  41  Jan 5 2004                   stabbing              friend
## 2    Male  46  Jan 8 2004            pick axe wounds              friend
## 3    Male   0 Jan 15 2004 asphyxiation (suffocation)              mother
## 4  Female  46  Feb 1 2004         blunt force trauma             partner
## 5    Male  10  Feb 2 2004                   stabbing              father
## 6  Female   2  Feb 2 2004                   stabbing              father
## 7    Male  36  Feb 4 2004                   stabbing partners ex-partner
## 8    Male  20  Feb 8 2004                  car crash              friend
## 9    Male  29  Feb 8 2004         blunt force trauma           strangers
## 10 Female  32 Feb 15 2004         blunt force trauma             husband
##                       name  full_date    month          cause_cat     region
## 1           Donald Linwood 2004-01-05  January     Violent weapon Canterbury
## 2              James Weeks 2004-01-08  January     Violent weapon Canterbury
## 3  Gabriel Harrison-Taylor 2004-01-15  January           Asphyxia   Auckland
## 4    Odette Lloyd-Rangiuia 2004-02-01 February Blunt force trauma Canterbury
## 5          Te Hau OCarroll 2004-02-02 February     Violent weapon Wellington
## 6         Ngamata OCarroll 2004-02-02 February     Violent weapon Wellington
## 7          Darryn McRobert 2004-02-04 February     Violent weapon Canterbury
## 8           Peretiso Sauni 2004-02-08 February          Car crash   Auckland
## 9           Shannon McComb 2004-02-08 February Blunt force trauma Canterbury
## 10        Asolelei Sameulu 2004-02-15 February Blunt force trauma   Auckland
##                      geometry
## 1  POINT (171.6442 -43.63394)
## 2  POINT (172.1305 -43.28563)
## 3  POINT (174.8498 -36.92575)
## 4  POINT (172.6327 -43.55006)
## 5  POINT (175.1195 -40.73297)
## 6  POINT (175.1193 -40.73273)
## 7  POINT (172.5172 -43.53866)
## 8  POINT (174.7335 -36.89708)
## 9  POINT (172.6429 -43.54363)
## 10 POINT (174.6274 -36.90353)

iraq_terrorism

The Global Terrorism Database (GTD) documents information on terrorism events worldwide; some of these data have been and packaged in stelfi as iraq_terrorism.

## Simple feature collection with 4208 features and 16 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 38.92288 ymin: 30.51005 xmax: 47.7781 ymax: 36.92948
## CRS:           +proj=longlat +datum=WGS84 +no_defs +ellps=WGS84 +towgs84=0,0,0
## First 10 features:
##       iyear imonth iday country success nkill specificity
## 18055  2013      4   18    Iraq    TRUE    28           1
## 18109  2013      4   20    Iraq    TRUE     0           1
## 18110  2013      4   20    Iraq    TRUE     0           1
## 18111  2013      4   20    Iraq    TRUE     0           1
## 18864  2013      5   16    Iraq    TRUE     3           1
## 18865  2013      5   16    Iraq    TRUE     3           1
## 18866  2013      5   16    Iraq    TRUE     2           1
## 18867  2013      5   16    Iraq    TRUE     3           1
## 19161  2013      5   27    Iraq    TRUE     6           1
## 19166  2013      5   27    Iraq    TRUE     1           1
##                                             gname   x_coord   y_coord   z_coord
## 18055 Islamic State of Iraq and the Levant (ISIL) 0.5974251 0.5844656 0.5490748
## 18109 Islamic State of Iraq and the Levant (ISIL) 0.5997164 0.5864987 0.5443892
## 18110 Islamic State of Iraq and the Levant (ISIL) 0.5992751 0.5859289 0.5454876
## 18111 Islamic State of Iraq and the Levant (ISIL) 0.5959873 0.5733453 0.5622049
## 18864 Islamic State of Iraq and the Levant (ISIL) 0.5974251 0.5844656 0.5490748
## 18865 Islamic State of Iraq and the Levant (ISIL) 0.5974251 0.5844656 0.5490748
## 18866 Islamic State of Iraq and the Levant (ISIL) 0.5974251 0.5844656 0.5490748
## 18867 Islamic State of Iraq and the Levant (ISIL) 0.5876310 0.5507342 0.5927745
## 19161 Islamic State of Iraq and the Levant (ISIL) 0.5974251 0.5844656 0.5490748
## 19166 Islamic State of Iraq and the Levant (ISIL) 0.5974251 0.5844656 0.5490748
##       popdensity luminosity         tt    utm_x      utm_y
## 18055  0.4065874  1.0924644 -0.3210921 333098.1 4007920.00
## 18109 -0.3479151  0.2298066 -0.2726546 407264.8 5332968.87
## 18110 -0.3479432  0.9717434 -0.3210921 401682.9 5252649.56
## 18111 -0.3783331  1.0521158 -0.3210921 405272.2 5344797.97
## 18864  0.4065874  1.0924644 -0.3210921 595450.3 4078540.46
## 18865  0.4065874  1.0924644 -0.3210921 595450.3 4078540.46
## 18866  0.4065874  1.0924644 -0.3210921 723492.7   45579.28
## 18867 -0.3665068  1.0924644 -0.3210921 815931.5  435892.29
## 19161  0.4065874  1.0924644 -0.3210921 252226.3 3703963.04
## 19166  0.4065874  1.0924644 -0.3210921 756886.0 4023175.15
##                        geometry
## 18055 POINT (44.37177 33.30357)
## 18109  POINT (44.3616 32.98293)
## 18110 POINT (44.35484 33.05799)
## 18111 POINT (43.89071 34.20842)
## 18864 POINT (44.37177 33.30357)
## 18865 POINT (44.37177 33.30357)
## 18866 POINT (44.37177 33.30357)
## 18867 POINT (43.14357 36.35415)
## 19161 POINT (44.37177 33.30357)
## 19166 POINT (44.37177 33.30357)

1.3 Simulated data

xyt

In this chapter a log-Gaussian Cox process is fitted to these data and in this chapter a spatiotemporal selfexciting model is fitted.

## Simple feature collection with 654 features and 1 field
## Geometry type: GEOMETRY
## Dimension:     XY
## Bounding box:  xmin: 0 ymin: -2.974928 xmax: 12.56637 ymax: 2.974928
## CRS:           NA
## First 10 features:
##     label                           geom
## 1  window POLYGON ((10.77117 -2.78183...
## 2   point       POINT (6.8074 -2.034423)
## 3   point     POINT (7.558362 -2.193865)
## 4   point     POINT (8.085083 -2.080938)
## 5   point     POINT (8.121308 -2.522357)
## 6   point     POINT (8.362448 -2.303117)
## 7   point     POINT (9.000749 -2.955328)
## 8   point     POINT (9.147803 -2.243146)
## 9   point     POINT (9.261744 -2.408326)
## 10  point      POINT (8.532312 -2.48986)

marked

In this chapter a marked log-Gaussian Cox process is fitted to these data.

## Simple feature collection with 159 features and 3 fields
## Geometry type: POINT
## Dimension:     XY
## Bounding box:  xmin: 0.006606752 ymin: 0.006502493 xmax: 2.985087 ymax: 2.938558
## CRS:           NA
## First 10 features:
##           m1 m2        m3                     geometry
## 1  10.008609  0  9.616468 POINT (0.08935799 0.5756269)
## 2   8.730592  0  6.918024     POINT (2.177973 2.90455)
## 3  11.330677  0 16.798212    POINT (2.250791 1.024792)
## 4  11.338656  0  8.073566    POINT (2.033398 1.038773)
## 5   9.395725  0  9.977866   POINT (2.777002 0.4685442)
## 6  10.331965  0 10.615245   POINT (0.5988652 2.422233)
## 7  10.069787  0 11.268171   POINT (1.541071 0.9307671)
## 8   9.717775  0 13.306125    POINT (2.615062 1.064561)
## 9  10.071326  0 18.300715   POINT (0.3882139 2.146845)
## 10 10.147740  0 16.751740     POINT (1.501552 1.64466)

horse_mesh

In this chapter we illustrate different geometric metrics of this triangulation.

## Simple feature collection with 396 features and 4 fields
## Geometry type: POLYGON
## Dimension:     XY
## Bounding box:  xmin: -17.96875 ymin: -11.78261 xmax: 17.26563 ymax: 11.65217
## CRS:           NA
## First 10 features:
##     V1  V2  V3 ID                       geometry
## 1  172  30 186  1 POLYGON ((8.441837 -2.16176...
## 2   28 188 162  2 POLYGON ((10.43359 0.913043...
## 3  168 186  42  3 POLYGON ((5.818232 -3.05894...
## 4  117  57  63  4 POLYGON ((-3.660156 -8.0326...
## 5  270 253 121  5 POLYGON ((-8.43636 2.023352...
## 6   92 144 169  6 POLYGON ((-8.042969 4.47826...
## 7  175 137 240  7 POLYGON ((5.689521 -1.13385...
## 8  182 148 111  8 POLYGON ((10.50244 7.199319...
## 9  253 169 121  9 POLYGON ((-7.850425 2.87106...
## 10  14  15 116 10 POLYGON ((13.3125 11.56522,...