This session will be held in the Erskine Building, Room 446
15:40 — 16:00
Ian Westbrooke
Department of Conservation
I will introduce a small threatened native bird - the rock wren, and provide resources on the bird itself to set the context. I will then explore a small dataset exactly as it came to me from remote mountains in Fiordland on this fascinating bird's population status. There are 24 numbers - counts from 12 grids of 25 hectares in each of 1984/5 and 2005. This data gives a great opportunity to create tables and graphs, and calculate means, by hand or using a tool like Excel, tasks suitable for both junior and senior classes. For year thirteen students, the data poses the question asked by the person who sent the data - what is a confidence interval for the average change in the population per grid square. A confidence interval can be created using either traditional or resampling techniques.
16:00 — 16:20
Adam N. H. Smith
National Institute of Water and Atmospheric Research Ltd. (NIWA)
Hector's dolphins (Cephalorhynchus hectori) are the smallest and rarest marine dolphin in the world. Two geographically separated populations of Hector's dolphin exist: one on the west coast near Auckland and one around the South Island. In 2002, I was asked to help uncover whether the North Island population was a separate subspecies from the larger South Island population, following a study that showed considerable genetic differences between them. To address this question, we examined the skulls of Hector's dolphins held by various museums around the country to compare the two populations. The North Island dolphins were shown to be sufficiently distinct in head size and shape to those from the South Island to be recognised as a new subspecies, Maui's dolphin (Cephalorhynchus hectori maui). Here, I will demonstrate some exploratory analysis of the skull data that were used in this study, focusing primarily on graphical methods.
16:20 — 16:40
Michelle Wood
IAG New Zealand Limited
Whilst we live to fit the model and answer the question of life there is often much work and many hours spent at the computer looking at, and trying to decipher the data. It can be an art form to extract meaningful information from databases not designed with statistical analysis in mind. This talk is a lighted hearted look at some of the discoveries that I have made about different data that I have handled in preparation for statistical analysis within a variety of industries, ranging from clinical trials research through to commercial lines insurance pricing. There are some useful database design basics that can assist us in the understanding of the data structure. Once the data structure is understood then attention is drawn to the variables and their content, which can have some interesting challenges especially in industries where information may be secondary to doing business and data quality doesn't have a high priority. I hope to share some of my successes and failures in handling data from different sources and offer some advice that may assist you in maximising the value you can extract from your data sources.
16:40 — 17:00
Sharleen Forbes & Emma Mawby
Statistics New Zealand
Teachers of statistics need unit-record datasets that are rich with relevant information. Official Statistics agencies have many such datasets, but need to keep them confidential. Our first SURF for schools aims to move towards meeting both these needs. It contains seven variables on 200 synthetic people. These people were designed to have very similar characteristics to 8,500 real people in the NZ Income Survey of June 2004. We will describe how we worked from the CURF (Confidentialised Unit Record File) for the Income Survey, to the SURF. The SURF is intended for learners, and the CURF is intended for researchers. We will do some school-friendly analysis on both, and assess the validity of results that learners would get from the SURF. The SURF comes with classroom-ready activities that we will outline. Copies of the SURF for Schools CD will be available.