20 research outputs found
Programming: Predicting student success early in CS1. A re-validation and replication study
This paper describes a large, multi-institutional revalidation study conducted in the academic year 2015-16. Six hundred and ninetytwo students participated in this study, from 11 institutions (ten institutions in Ireland and one in Denmark). The primary goal was to validate and further develop an existing computational prediction model called Predict Student Success (PreSS). In doing so, this study addressed a call from the 2015 ITiCSE working group (the second Grand Challenge ), to systematically analyse and verify previous studies using data from multiple contexts to tease out tacit factors that contribute to previously observed outcomes . PreSS was developed and validated in a longitudinal study conducted over a three year period (twelve years previous from 2004- 06). PreSS could predict with near 80% accuracy, how a student would likely perform on an introductory programming module. Notably this could be achieved at a very early stage in the module. This paper describes a revalidation of the original PreSS model on a significantly larger multi-institutional data set twelve years after its initial development and looks at recent research on additional factors that may improve the model. The work involved the development of a fully automated end-to-end tool, which can predict student success early in CS1, with an accuracy of 71%. This paper describes, in detail the PreSS model, recent research, pilot studies and the re-validation and replication study of the PreSS model
Multi-decadal shoreline changes in Eastern Ghana—natural dynamics versus human interventions
Human infrastructures, such as dams, seawalls, and ports, can affect both the sedimentary budget and nearshore hydrodynamics,
enhancing and accelerating the loss or gain of coastal sediments. Understanding the processes and factors controlling
beach morphodynamics is essential for implementing adequate adaptation strategies in coastal areas, particularly in those
regions where coastal protection measures are scarce. This study analyzes shoreline changes in the Keta Municipal District,
located in southeastern Ghana (West Africa). This area is characterized by the sedimentary input of the Volta River, forming
a river delta situated to the west, i.e., updrift, of our study site. Following the construction of two dams (Akosombo and
Kpong) on the Volta River in 1965 and 1982, groins and revetments have been built along the coast between 2005 and 2015
to reduce the high rates of coastal erosion in this area. Here, we explore the influence of these dams and the hard protection
constructions on beach morphodynamics using historical maps and satellite images complemented by a shoreline survey
undertaken with a differential GNSS in 2015. The multi-decadal evolution between 1913 and 2015 reconstructed for 90 km
of shoreline suggests that local erosion rates in the region predate the construction of the two dams on the Volta River,
indicating that these structures might not be the primary driver of coastal erosion in this area, as previously suggested. We
emphasize that delta dynamics under conditions of high-energy longshore drift, modified by anthropogenic drivers such as
sand mining, play a key role in the long-term evolution of this coast. Our results also show that the infrastructures built to
halt coastal erosion result in localized erosion and accretion down-current along the coastline towards the border with Togo,
highlighting the need for a transnational perspective in addressing the problems caused by coastal erosion