A series of studies have been conducted on the phenomenon of co-offending from the aspects of relationship and relationship structure of offenders, but there is a lack of stability analysis on the regional relationship between offenders. Based on the data of the street fraud cases in Beijing in 2005, 2010, and 2014, this study constructed a regional relation network model of offenders based on the principle of social network, and analyzed the structural characteristics and changing trend of the regional relation network of offenders participating in co-offending by means of network analysis. The main results are as follows. The spatial distribution of origins of offenders participating in the co-offending in Beijing was gradually concentrated, and a pattern of coexistenting multicenters was formed with North China as the main area. The small-world effect of regional relation network of offenders gradually strengthened and developed from power-law distribution mode to exponential distribution mode. Among the offenders who participated in the co-offending, the influence of offenders from Beijing gradually decreased, while that of offenders from Hebei Province gradually increased. The cohesive subgroup structure of the regional relation network of offenders gradually polarized, and a few offender regional subgroup structures that are closely related to co-offending appeared. This study also explored the reasons for the existence and evolution of the cross-area co-offending network from the perspectives of social relation reconstruction and subculture of floating population. The results of this study have some implications for the further research on the relationship pattern of the offenders' co-offending.

As a significant spatiotemporal characteristic of crimes, repeat and near repeat pattern has received much interest in criminology research. The purpose of this study was to explore the formation process and features of crime hotspots by using near repeat principle. Robbery cases in six districts of Beijing inner city from 2012 to 2014 were used to examine the extent to which repeats and near repeats spatially intersect robbery hotspots. All the case chains within crime hotspots satisfying repeat and near repeat principle were screened out. From this, by dividing the case characteristics into criminal factors and environmental factors, the characteristics of case chains were analyzed to describe the features and formation of hotspots. The results suggest that there were three main crime hotspots in the six districts of Beijing inner city, namely "a", "b", "c", and most of the cases located within the hotspots were repeats and near repeats. The hotspot "a" was located in Shuangjing and Jinsong, and the hotspot "c" was located in Dahongmen Bridge. The characteristics of the criminal factors of these two hotspots were more consistent than that of the environmental factors, which indicates that the formation of the hotspots were more likely to originate from the repeated crimes committed in the area by criminals. The hotspot "b" was located in Fenzhongsi area by the southeastern third ring road. The characteristics of the environmental factors of this hotspot were more consistent than that of the criminal factors, which indicates that the formation of the hotspot was more likely to originate from different criminals committing crimes in this area. The research findings presented in this article can aid decision making on crime prevention and detection in policing.

Explaining the choice of crime location is one of the central themes of crime geography. The existing research on the choice of the location where street robbers commit crimes mainly focuses on the following two aspects: analyzing the spatial pattern and influencing factors from a comprehensive perspective, and analyzing the time difference from a comparative perspective. In general, these studies not only enrich the research perspectives, but also clarify the spatiotemporal patterns and their formation mechanisms. Therefore, they have important theoretical and practical significance. The literature also shows that offenders' subsequent crime location choices are affected by their prior crime location choices. However, the published studies have focused on the influences of time and place of a previous crime, and have not yet verified the role of crime experiences of the former offense. Therefore, this study further examined the influence of the prior individual robbery experiences on the subsequent street robbery location choices by using a mixed logit model and data on arrested robbers in ZG City, China. The results suggest that the individual criminal experiences of street robbers such as the interval of crimes, criminal travel, and arrest on the spot have a strong effect on subsequent street robbery location choices, that is, a shorter time interval, a shorter distance of journey to prior crime location, and less possibility of being arrested in the act of a prior street robbery significantly increase the likelihood of a robber returning to the previous location. Finally, through police interviews and theoretical analysis, it is found that the last situation is formed by the offenders' fear of being arrested on the spot, the special ways of police intervention, as well as the social cohesion and crime prevention of communities. Therefore, the extension of the results may well provide references for the police departments' work on prevention and pre-event control and active intervention.

As a ticklish social problem, crime committed in hotels has been concerned by both Chinese and Western scholars. Theft is one of the most frequent crime types occurred in hotels, especially in star hotels. Previous studies on influencing factors of hotel theft cases mainly focused on star hotel and personal attributes of victims at the micro level from the perspective of sociology, rather than considering the built environmental factors at the macro level from the perspective of geography. Using the data on the star hotels with theft cases in 2012-2014 in ZG central city obtained from Municipal Public Security Bureau, this study examined the spatial-temporal characteristics of these hotels. Then the environmental indicators within 500 m around the hotels were examined and the negative binomial regression method was used to make a systematic analysis on the factors affecting the theft of different types of star hotels in various time periods. The main results are as follows: 1) The spatial-temporal distribution of star hotels showed obvious agglomeration features. Generally, most of the main hotspots in the high incidence areas of hotel theft were time invariant, all of them are highlighted near the old city central business district, the eastern extension of the main road and the railway station. However, the spatial distribution of secondary hotspots was time-varying. 2) The overall model analysis indicates that the improvement of the service level was the most effective way to reduce the theft cases of all star hotels. The surrounding property and community points of interest (POIs) will significantly increase the opportunity for all star hotels to be stolen, while road intersections play a significant regulatory role in the theft of all star hotels. 3) The results of the sub models demonstrate that the effect of service level on the theft of three-star and five-star hotels is significant, and the effect of road intersection on the theft of four-star hotels often used by guests of business travel is stronger; the number of POIs has more obvious effect on three-star and four-star hotels. Large-scale retail business center can significantly increase the number of theft cases in hotels in the peak season and the weekend, and the number of road intersections is significant for the monitoring of stolen risk of the star hotels in the off-season period and the working days. These results have shown that the built environment played a significant role in affecting the opportunity and cost of hotel theft. The results verify the applicability of the daily activity theory in the study of hotel crimes in large cities in China, and expand the research results of crime geography in the direction of star hotel theft, which has a guiding effect for the prevention of hotel theft.

Drug crime is a criminal act of common concern in many places of the world. Many scholars have carried out research from different professional fields. The causes of drug-related crimes have been analyzed in the existing literature. Because of the limitations of data, there is little research on the spatial and temporal distribution of drug-related crime hotspots at the micro-scale. This study took NH and DM residential communities in SZ as an example. Based on the data of drug crime cases, this study used exploratory data analysis and spatiotemporal scanning to identify the distribution of hotspots of drug crimes. Then, by combining the spatial data of land use types and dynamic population flow, it quantitatively analyzed the influencing factors of the spatiotemporal distribution pattern of drug crime cases. The results show that: 1) Drug crimes mainly distribute in developed commercial areas and urban villages, and the hotspot distribution of drug crimes in urban villages occurred earlier than in developed commercial areas, and the scope of influence is larger in the former; 2) The distribution of drug crimes in different land types is uneven; the land use types of accommodation, tourism, and entertainment, wholesale and retail commercial department stores, and catering and business services are highly correlated with drug crimes. 3) The proportion of the area in hotspot areas with high flow of people has a certain correlation with the occurrence of drug crimes. When the proportion of hotspot areas is greater than 5% or 0, it can restrain the occurrence of drug-related crimes; when the proportion of hotspot areas is between 0 and 5%, it can promote the occurrence of drug-related crimes.

Child trafficking crime causes physical and psychological trauma to the victims and great grief and long-term trouble to the families of the victims. Therefore, it has attracted the attention of the society and the academic community. Research from the perspective of criminal geography in this field started relatively late and mainly focused on the macro analysis, so it is urgent to focus on high-incidence areas and key groups for detailed analysis. Based on the data of Sichuan Province—the most severely affected area for trafficking crime in China—this study analyzed the spatiotemporal pattern and influencing factors of child trafficking crime by means of text analysis, mathematical statistics, spatial analysis, and case analysis. The study found that: 1) The trafficked children were mainly from rural areas, and the trafficked males were significantly more than females. The trafficked children tended to be young, showing a double-peaks pattern. 2) Temporally, the annual change of crime showed a roughly inverted V-shaped pattern, which frequently occurred during 1981-2000. The trafficking crime was concentrated in the summer half year. 3) Spatially, the number of trafficked children was unevenly distributed. There was a high-incidence area (Chengdu) and a few smaller high-incidence areas. At the county scale, the crime pattern presented the characteristics of "high-high" and "low-low" distribution and trafficking-out hotspots continue to spread south and east. The trafficking routes presented a decentralized trafficking-in to the east feature, which showed that South China and North China were the main trafficking-in areas. 4) Through the analysis of the causes of the high incidence of crimes from 1981 to 2000, it was found that education level and the income gap between urban and rural areas were the main factors that affect the crime of child trafficking.