IPAC - Individual Peer Assessment of Contribution to group work

Universities and professional bodies recognize the educational benefits of getting students to work in groups in several projects across their degrees. However, staff and students have concerns about the fairness of the traditional assessment, when all members of the team get the same mark. In particular, this leads to poor student experience and numerous complaints of ‘free ridders’, significantly affecting the NSS scores. The IPAC Consortium was formed to look into the use of Individual Peer Assessment of Contribution (IPAC) to group work. We present the different areas in which we have been working, e.g. from the basics of the methodology to the various specifics during implementation, literature review, collection of staff and student perception at UCL, review of software/platforms to run the method, tests and case studies within UCL, guidelines, development of a customizable and easy tool to run IPAC, etc. We will also consult the audience for additional priority areas that we should explore and invite them to the Consortium

Using IPAC across disciplines and methodologies- what are the typical marks given by students to peers?

The IPAC methodology allows academics to give an individual mark to students that participated in a group work activity, and this is based on their contributions as seen by their peers. Different formulas are used to combine the “group mark” and the “IPAC value” into the “individual marks”, and the selection is mostly driven by how confident and comfortable the academic staff is giving “power” to the students to influence the final marks. In reality, any scepticism or lack of confidence comes from not knowing how students typically rate their peers. This paper provides insightful information by reporting significant statistical analysis on a large data set of the typical IPAC marks given by the students in several group activities run in 2017/18 across UCL, and what might influence these marks, e.g. the specific method used for IPAC, how it was implemented, the class experience, etc. This is of interest to present and future users of the IPAC methodology

Home-made and readily available IPAC tool – Run your practice your way and efficiently

The concept of the IPAC methodology is simple, however its implementation without a tool is very staff-time consuming (e.g. 3-4 full working days for an 80 students class) and hence not always used even if beneficial. Therefore an automatic IPAC system is needed. This system should comply with some priority requirements that I identified from extensive literature reading, own experience and numerous conversations with other staff members. There are some relevant commercial systems available (reviewed by the IPAC Consortium), but currently none meet all these priority requirements. This drove me to develop an in-house software. This is currently available, in use by some UCL academics in various Faculties since October 2017, and readily available to others. This software is useful to any academic/teacher setting and assessing group work. I will present the priority requirements and give a demonstration of the software. Feedback / future development priorities will be sought from the audience

Individual peer assessment of contribution to group work: methodology, results and insights [Presentations and round table]

Round table where the IPAC topic was discussed and 9 abstracts from IPAC Consortium members were presented. 90 mins sessio

An Isolated Stellar-Mass Black Hole Detected Through Astrometric Microlensing

We report the first unambiguous detection and mass measurement of an isolated stellar-mass black hole (BH). We used the Hubble Space Telescope (HST) to carry out precise astrometry of the source star of the long-duration (t_E ~ 270 days), high-magnification microlensing event MOA-2011-BLG-191/OGLE-2011-BLG-0462, in the direction of the Galactic bulge. HST imaging, conducted at eight epochs over an interval of six years, reveals a clear relativistic astrometric deflection of the background star's apparent position. Ground-based photometry shows a parallactic signature of the effect of the Earth's motion on the microlensing light curve. Combining the HST astrometry with the ground-based light curve and the derived parallax, we obtain a lens mass of 7.1 +/- 1.3 M_Sun and a distance of 1.58 +/- 0.18 kpc. We show that the lens emits no detectable light, which, along with having a mass higher than is possible for a white dwarf or neutron star, confirms its BH nature. Our analysis also provides an absolute proper motion for the BH. The proper motion is offset from the mean motion of Galactic-disk stars at similar distances by an amount corresponding to a transverse space velocity of ~45 km/s, suggesting that the BH received a modest natal 'kick' from its supernova explosion. Previous mass determinations for stellar-mass BHs have come from radial-velocity measurements of Galactic X-ray binaries, and from gravitational radiation emitted by merging BHs in binary systems in external galaxies. Our mass measurement is the first ever for an isolated stellar-mass BH using any technique