Handling missing data by re-approaching non-respondents

When handling missing data, a researcher should be aware of the mechanism underlying the missingness. In the presence of non-randomly missing data, a model of the missing data mechanism should be included in the analyses to prevent the analyses based on the data from becoming biased. Modeling the missing data mechanism, however, is a difficult task. One way in which knowledge about the missing data mechanism may be obtained is by collecting additional data from non-respondents. In this paper the method of re-approaching respondents who did not answer all questions of a questionnaire is described. New answers were obtained from a sample of these non-respondents and the reason(s) for skipping questions was (were) probed for. The additional data resulted in a larger sample and was used to investigate the differences between respondents and non-respondents, whereas probing for the causes of missingness resulted in more knowledge about the nature of the missing data patterns

The use of video imagery to analyse groundwater and shoreline dynamics on a dissipative beach

Groundwater seepage is known to influence beach erosion and accretion processes. However, field measurements of the variation of the groundwater seepage line (GWSL) and the vertical elevation difference between the GWSL and the shoreline are limited. We developed a methodology to extract the temporal variability of the shoreline and the wet-dry boundary using video imagery, with the overarching aim to examine elevation differences between the wet-dry boundary and the shoreline position in relation to rainfall and wave characteristics, during a tidal cycle. The wet-dry boundary was detected from 10-minute time-averaged images collected at Ngaranui Beach, Raglan, New Zealand. An algorithm discriminated between the dry and wet cells using a threshold related to the maximum of the red, green and blue intensities in Hue-Saturation-Value. Field measurements showed this corresponded to the location where the watertable was within 2 cm of the beachface surface. Timestacks, time series of pixels extracted from cross-shore transects in the video imagery, were used to determine the location of the shoreline by manually digitizing the maximum run-up and minimum run-down location for each swash cycle, and averaging the result. In our test data set of 14 days covering a range of wave and rainfall conditions, we found 6 days when the elevation difference between the wet-dry boundary and the shoreline remained approximately constant during the tidal cycle. For these days, the wet-dry boundary corresponded to the upper limit of the swash zone. On the other 8 days, the wet-dry boundary and the shoreline decoupled with falling tide, leading to elevation differences of up to 2.5 m at low tide. Elevation differences between the GWSL and the shoreline at low-tide were particularly large when the cumulative rainfall in the preceding month was greater than 200 mm. This research shows that the wet-dry boundary (such as often used in video shoreline-finding algorithms) is related to groundwater seepage on low-sloped, medium to fine sand beaches such as Ngaranui Beach (mean grain size~0.27 mm, beach slope ~1:70) and may not be a good indicator of the position of the shoreline

Writing Circle | Spring into Summer

There’s a gap in-between spring and summer. Use this time to join the CETL in a 6-week writing circle. This time can be spent writing anything. One of the biggest challenges with finding time to write is making it a habit and sitting down to write. This writing circle will give you the space to write and hopefully make a new habit of writing that you can carry over into the future

Small Teaching and Small Teaching Online | Learning Circle

The Center of Excellence in Teaching in Learning (CETL) would like to announce a learning circle that will operate as a community of practice (COP), utilizing the science behind two books to reflect and apply these principles to the craft of teaching. Small Teaching by James Lang (2016) and Small Teaching Online by Flower Darby and James Lang (2019) explore the concept of how we can improve our teaching by doing small manageable things to improve. The books may be purchased or accessed online at Z-library. Please join us for a 4-month opportunity to focus on your teaching in a learning community. You will find this opportunity to be engaging, motivating, and beneficial to you as the instructor, but most importantly to your students

Writing Circle | 2019-2020

Have you been writing and article, book, or anything in between that you are struggling to find time for? Or are you in a rut with your writing? If so, join us for an information meeting about an upcoming 5-week series

We\u27re Over It… But Are We? | Reflection and Discussion

This academic year has been different. Teaching during a global pandemic has challenged us and shifted much of our teaching. We\u27re over it... but are we? We may be over the pandemic, but what about the big shifts we had in our teaching this year? How will these forever change our pedagogy and our content? What things from this year will we take with us into our future teaching? Join us for a 1-hour reflective discussion about how the pandemic has changed our teaching and how we may find the silver lining in some of challenges and changes. To be an intentional teacher we must reflect, join us in this group reflection to reflect our teaching from this academic year

Writing Circle | Spring 2022

Are you writing something? Wanting to write more? Wanting to start a new project? let\u27s start the semester off right with good habits. One of the biggest challenges with finding the time to write is making it a habit and sitting down to write. This writing circle will give you the space to write and hopefully make a new habit of writing that you can carry over into the future. if you have never joined one of the writing circles, now is your time! You won\u27t regret it. Benefits of the Writing Circle Engage with other faculty to discuss your writing and other projects. Find time to write. Be inspired by your colleagues

Dead Ideas in Teaching and Learning | Learning Circle

Why do we do what we do in the classroom? Science does not back all of our pedagogy. What ideas are dead in teaching and learning? What ideas should we reflect on and alter for the benefit of being effective, inclusive, and engaging instructors? Join the CETL for a 4-meeting series where we will listen to a podcast series Dead Ideas in Teaching and Learning through Columbia University. We will meet to discuss various ideas and reflect on the podcasts and our personal practices. If you like listening to podcasts, this one\u27s for you! Each meeting we will chat about 2 different podcasts Podcasts range in time from 20-45 minutes. Benefits of the Learning Circle Engage with other faculty about teaching Develop your teaching skills (reflect on dead practices ) Increased enjoyment in teaching, decreased burnout, and enhance student outcomes in your class(es) Professional development certificate after completion can an be used as part of a dossier or self-evaluation