Missing Data in Quantitative Social Research

Almost invariably, the data available to the social scientist display one or more characteristics of missing information. Even though reasons for non response are varied, most frequently, they reflect the unwillingness of respondents to provide information on undesirable social behaviours and on issues considered as private. Besides these, sloppy research designs often leads to ambiguous and poorly structured survey questions which provide a recipe for low response. Longitudinal surveys also suffer from incompleteness due to attrition resulting from death and emigration, while in retrospective surveys, memory effect might be a major source of non-response. While there is no consensus among methodologists on the single most effective technique of handling missing information, certain pertinent questions need to be addressed: should we completely ignore the missing data and proceed with the analysis? What are the implicit assumptions if one adopts such an approach and how unbiased will our estimates be? This paper reviews a variety of methods of handling missing information

Residential Location and Intra City Mobility in an African City: Some Empirical Observations among Migrants in Metropolitan Accra, Ghana

Although many facets of the migration phenomena in sub-Saharan Africa have been studied extensively, there is a paucity of research on residential mobility behavior of migrants. This exploratory study examines the residential mobility in Accra, Ghana, using a retrospective survey of randomly selected migrant households. To examine the direction of moves, Accra was delineated into three major zones: the inner city, former periphery and recent periphery. The results demonstrate that unlike studies elsewhere, the inner zone of Accra does not serve as the major port of entry for migrants. While the former periphery served as the zone of entry for the majority of the migrants in the past, the recent periphery has become the predominant entry point in recent years, and has also become the zone to which most home owners eventually move. This change in the zone of entry over time has been explained through a ‘push-pull’ framework. Also, there is a significant association between ethnicity and area of initial residence. With the exception of the Akans, there is a marked concentration of ethnic groups in certain sectors of the city. For instance, almost two thirds of the Mole-Dagbanis initially settled in the former periphery. Using a multinomial logit model to estimate the direction of residential movement, it was found that although the majority of movements were intra-sectoral, different trajectories were observed for renters and home owners. The policy implications of the findings and directions for further research are discussed

Selection of Blast Design for Kofi C Pit of Endeavour Mining Corporation, Mali

The Kofi Gold Mine (KGM) of Endeavour Mining Corporation in Mali needed to select one of two alternative blast designs, Blast Design 1 (BD1) and Blast Design 2 (BD2), for the fresh rocks of the deposit, both ore and waste,  in their Kofi C Pit. BD1 has a burden of 3.2 m, a spacing of 3.5 m, a bench height of 5.0 m and a sub drill of 0.5 m. BD2 has a burden of 3.5 m, a spacing of 4.0 m, a bench height of 10.0 m and a sub drill of 0.8 m. Both designs have the same hole diameter of 115 mm and powder factor of  0.68 kg/m3. The Modified Kuz-Ram Fragmentation Model was used to estimate and compare the fragmentation of the two designs. The modelling results showed that the fragmentation of BD1 would be better than that of BD2 but cost analysis revealed that the drilling and blasting cost of BD2 would be lower than that of BD1. Consequently, BD2 was modified into Blast Design 3 (BD3) to improve the fragmentation without exceeding the drilling and blasting cost of BD1. The modification was done by increasing the powder factor of BD2 by 16.18 %. Subsequent fragmentation modelling and cost analysis revealed that BD3 and BD1 would now have the same fragmentation and the same drilling and blasting cost but BD3 would give a higher productivity. It was therefore recommended that KGM selects BD3 over BD1 and BD2 for ore drilling and blasting. BD2 could be considered for waste drilling and blasting because its lower fragmentation, which is not good enough when the rock is ore, is acceptable when the rock is waste. Keywords: Blast Design, Cost Analysis, Drilling and Blasting Productivity, Kuz-Ram Fragmentation Mode

Counselling Needs of Pupils with Special Educational Needs and Disabilities in the Greater Accra Region of Ghana: Implications for Inclusive Education in Ghana

In this fast changing world, pupils all over the world have developed severe social and psychological needs that affect their interactions with others and subsequently, the achievement of their life goals. Essentially, the social and psychological needs of school pupils have manifested in diverse mal-adjusted behaviours that hinder their academic performance. The study explored the various counselling needs of pupils with special educational needs and disabilities in one of the regions of Ghana and the specific level at which pupils require guidance and counselling services. The purposive and systematic sampling techniques were employed to select 88 pupils and three staff from three special schools from the region to provide information for the study with the use of questionnaire and interview format. The study revealed that pupils had various counselling needs including social, emotional, career, physical and health. On the basis of the findings, some recommendations were made for intervention. Key words: special educational needs, guidance and counselling, psychological needs, pupil

A Model to Determine the Number of Rescue Brigades in Underground Mines using the Risk Factor Approach

Mine rescue practices have seen significant improvement over the century. There have been developments in breathing apparatus, safe havens, rescue capsules, rescue simulators, underground communication technology, and training for rescue brigades. Most countries practice a mine-owned rescue system and the number of rescue brigades required in a mine is country-specific and determined by the mining regulations of the host country. A review of mining regulations globally shows that the number of brigades required in a mine depends solely on the number of people employed underground. For ages, this has been the only criterion used to determine the number of rescue brigades required in a mine. This criterion is not appropriate since there are other vital factors which must be taken into account. Considering the nature, complexity and innovations in mining operation currently, this paper considers eleven (11) factors that influence the number of rescue brigades in a mine. These eleven (11) factors were subjected to focus group discussions, the Classical Analytical Hierarchy Process, and the Fuzzy Analytical Hierarchy Process to establish seven (7) vital factors with weights more appropriate for determining the number of rescue brigades required in a mine. The results show that the number of rescue brigades required in a mine depends on: the safety culture of the mine; the number of people employed per shift; the resourcefulness of the rescue team; the number of active mines in the mine; the level of mechanisation of the mine, the mining depth; and the nearness and responsiveness of sister rescue teams. A novel model called the Yenzanya Model has been derived for determining the number of rescue brigades for underground mines as a contribution to science. This should be adopted by mine regulators to determine the number of brigades required for mining projects

Assessment of Ore Grade Estimation Methods for Structurally Controlled Vein Deposits - A Review

Resource estimation techniques have upgraded over the past couple of years, thereby improving resource estimates. The classical method of estimation is less used in ore grade estimation than geostatistics (kriging) which proved to provide more accurate estimates by its ability to account for the geology of the deposit and assess error. Geostatistics has therefore been said to be superior over the classical methods of estimation. However, due to the complexity of using geostatistics in resource estimation, its time-consuming nature, the susceptibility to errors due to human interference, the difficulty in applying it to deposits with few data points and the difficulty in using it to estimate complicated deposits paved the way for the application of Artificial Intelligence (AI) techniques to be applied in ore grade estimation. AI techniques have been employed in diverse ore deposit types for the past two decades and have proven to provide comparable or better results than those estimated with kriging. This research aimed to review and compare the most commonly used kriging methods and AI techniques in ore grade estimation of complex structurally controlled vein deposits. The review showed that AI techniques outperformed kriging methods in ore grade estimation of vein deposits.   Keywords: Artificial Intelligence, Neural Networks, Geostatistics, Kriging, Mineral Resource, Grad

Mean Vector Analyses of the Voting Patterns of Ghanaians for Three Consecutive Periods: A Case Study of the Greater Accra Region

Abstract: The aim of this paper was to find out whether the outcome of future elections in the Greater Accra region could be predicted based on empirical data. The voting patterns of the presidential elections in Ghana deserve notice, not because of their political significance but because of the theoretical weight they carry. The shifts in electoral fortunes between the two main political parties in the country, especially in the greater Accra region provide a unique leverage for assessing theories of voting behavior. The paper uses statistical tools to examine the electoral performance of the four major political parties in Accra and the Hotelling's T 2 Statistic to test whether a prediction could be made to predict future outcomes of elections. Our results revealed that there was not enough statistical evidence to predict future outcomes of elections in the greater Accra district

The effectiveness of integrating educational robotic activities into higher education Computer Science curricula: a case study in a developing country

In this paper, we present a case study to investigate the effects of educational robotics on a formal undergraduate Computer Science education in a developing country. The key contributions of this paper include a longitudinal study design, spanning the whole duration of one taught course, and its focus on continually assessing the effectiveness and the impact of robotic-based exercises. The study assessed the students' motivation, engagement and level of understanding in learning general computer programming. The survey results indicate that there are benefits which can be gained from such activities and educational robotics is a promising tool in developing engaging study curricula. We hope that our experience from this study together with the free materials and data available for download will be beneficial to other practitioners working with educational robotics in different parts of the world

Correlates of Complete Childhood Vaccination in East African Countries.

Despite the benefits of childhood vaccinations, vaccination rates in low-income countries (LICs) vary widely. Increasing coverage of vaccines to 90% in the poorest countries over the next 10 years has been estimated to prevent 426 million cases of illness and avert nearly 6.4 million childhood deaths worldwide. Consequently, we sought to provide a comprehensive examination of contemporary vaccination patterns in East Africa and to identify common and country-specific barriers to complete childhood vaccination. Using data from the Demographic and Health Surveys (DHS) for Burundi, Ethiopia, Kenya, Rwanda, Tanzania, and Uganda, we looked at the prevalence of complete vaccination for polio, measles, Bacillus Calmette-Guérin (BCG) and DTwPHibHep (DTP) as recommended by the WHO among children ages 12 to 23 months. We conducted multivariable logistic regression within each country to estimate associations between complete vaccination status and health care access and sociodemographic variables using backwards stepwise regression. Vaccination varied significantly by country. In all countries, the majority of children received at least one dose of a WHO recommended vaccine; however, in Ethiopia, Tanzania, and Uganda less than 50% of children received a complete schedule of recommended vaccines. Being delivered in a public or private institution compared with being delivered at home was associated with increased odds of complete vaccination status. Sociodemographic covariates were not consistently associated with complete vaccination status across countries. Although no consistent set of predictors accounted for complete vaccination status, we observed differences based on region and the location of delivery. These differences point to the need to examine the historical, political, and economic context of each country in order to maximize vaccination coverage. Vaccination against these childhood diseases is a critical step towards reaching the Millennium Development Goal of reducing under-five mortality by two-thirds by 2015 and thus should be a global priority

Examining moral distress and injury resulting from the COVID-19 pandemic: Insights from the Ghanaian radiography workforce

Background Moral distress has been an issue under consideration in healthcare practice. The COVID-19 pandemic became a critical factor that contributed to heightened moral distress and injury among healthcare professionals, including radiographers. Despite the substantial engagement of radiographers in the management of COVID-19 patients, the consequent moral distress and injury states experienced by this critical frontline workforce have not been widely explored. This study investigated the level of moral distress and the coping mechanisms employed by radiographers in Ghana during the pandemic to provide valuable information to support radiographers and prepare the workforce better against any future pandemics. Methods Utilising a cross-sectional design, a survey approach was employed for data collection between June 2023 and August 2023 from clinically-active radiographers who worked before and during the pandemic in Ghana. Both descriptive and inferential statistics were generated using Microsoft Excel 2019 and the Statistical Package for the Social Sciences (v.26). Results Hundred (100) radiographers participated in the study. The result demonstrated that the COVID-19 pandemic escalated the risk of moral distress among radiographers from 22 % (n = 22) to 43 % (n = 43), with 33 % (n = 33) exhibiting signs of moral injury. This escalation impacted the mental health of 12 % (n = 12) of respondents and was reported as a contributor to career-changing decisions among radiographers. Notably, many of those affected did not seek formal support but relied on personal coping strategies and family support. Inadequate resources (69 %, n = 69), particularly regarding consumables, emerged as the primary cause of moral distress. The study underscored that the most effective means of mitigating moral distress in radiographers was through the provision of resources and additional staff support (66 %, n = 66). Conclusion This study sheds light on the state of moral distress and injury among radiographers during the COVID-19 pandemic, impacting the mental health of a minority and contributing to career-changing decisions. The findings emphasise the importance for healthcare institutions to proactively implement systems, such as resource provision, improved staffing, and emotional support, now and during similar future pandemics. This is crucial to address moral distress and cater to the mental health needs of radiographers, ensuring a resilient clinical radiography workforce