Videos and audio presentations
Note: images link to presentations
What is multilevel modelling? (mp4 video presentation, you may require Flash player plugin)
"Social science research is about trying to understand individual behaviour which can depend on a number of factors interacting in a complex way …"
presented by Fiona Steele
Multilevel Structures and Classifications (voice-over with video and slides, you may require Flash player plugin)
presented by Jon Rasbash. This presentation is the introduction to Module 4: Multilevel structures and classifications (sample PDF, 0.1 mb)
More about this subject - Multilevel Structures and Classifications
Random intercept models (voice-over with video and slides You may require Flash player plugin)
View transcript.
Random intercept models allow us to examine the relationship between two
variables after controlling for the clustering in our data; or to discover
to what extent differences between individuals in their values of some
variable are due to their membership of groups (such as schools or
countries) after controlling for their value on some other variable. This
presentation (based on a slightly older version of the slides from our
Introductory Workshop session on Random Intercept models) covers what
random intercept models are, what questions they can answer, what they look
like graphically and mathematically, how to interpret the results of
fitting a random intercept model, hypothesis testing, variance
partitioning coefficients, the correlation matrix, residuals and
predictions.
Presented by Rebecca Pillinger
Residuals - An Introduction (voice-over with video and slides You may require Flash player plugin)
View transcript
Residuals can be important if we want to rank our units after controlling
for a set of covariates (for example when drawing up league tables of
schools), or if we are interested in the effect of a particular level 2
unit (for example if we want to see what effect a particular school is
having on its students' performance).
In this presentation, we show how
both level 1 and level 2 residuals are calculated for multilevel models
(though in practice this calculation will usually be performed by the
software), and explain why residuals in multilevel models are shrunk in
towards the overall regression line.
Presented by Rebecca Pillinger
Measuring Dependency (voice-over with video and slides You may require Flash player plugin)
View transcript
We use multilevel modelling when we have dependent data, i.e. there is similarity between observations from the same group (for example, heights of children from the same family).
This presentation explains how to measure the dependency using the variance partitioning coefficient (VPC). We explore the interpretation of the VPC through example graphs. We also see that the VPC shows how much of the variance is due to each level of the model, and thus gives some insight into what extent the response is determined at each level.
Presented by Rebecca Pillinger
Covariance and Correlation Matrices (voice-over with video and slides You may require Flash player plugin)
View transcript.
We use multilevel modelling when we have dependent data, i.e. there is
similarity between observations from the same group (for example, heights
of children from the same family). An obvious question is: just how does
the multilevel model take this dependency into account? In this
presentation, we examine the structure of the model: we see what the
correlation is between each pair of level 1 units in our dataset. This
allows us to see how the relation between different observations from the
same group is specified by the model. We contrast this to a single level
model, for which we see there is no correlation between different
observations from the same group.
Presented by Rebecca Pillinger
Significance Testing (voice-over with video and slides You may require Flash player plugin) Presented by Kelvyn Jones
- Tests for coefficients of individual variables: eyeballing standard errors
- Wald tests
- Calculating p-values using the tail areas screen in MLwiN.
- Tests for comparing models: the Likelihood Ratio Test and the Deviance Information Criterion
Random slope models (voice-over with video and slides You may require Flash player plugin)
View transcript.
Random slope models allow us to explore the possibility that the
relationship between two variables may be different in different groups
(e.g. schools or countries). This presentation (based on a slightly older
version of the slides from our Introductory Workshop session on Random
Slope models) covers what random slope models are, what questions they can
answer, what they look like graphically and mathematically, how to
interpret the results of fitting a random slope model, hypothesis testing,
variance partitioning coefficients, and predictions.
Presented by Rebecca Pillinger
Using quantitative data in research
presented by Rebecca Pillinger
Introduction to online course, Module 1
Sample PDF document: Using quantitative data in research - Concepts* (PDF, 0.1 mb)
Introduction to quantitative data analysis
presented by Rebecca Pillinger
Introduction to online course, Module 2
Sample PDF document: Introduction to quantitative data analysis - Concepts* (PDF, 0.1 mb)
What is it and why you should do it (multilevel modelling) (voice-over with video and slides, to view this presentation you will require Internet Explorer and Flash player plugin)
presented by Jon Rasbash
Also available as a free download - jr.zip (zip, 16 mb). Please unzip the file and select 'Start Video'
Slides only: Why use multilevel modelling? (PowerPoint, 0.7 mb)
Global variations in health and mortality (voice-over with video and slides, to view this presentation you will require Internet Explorer and Flash player plugin)
presented by Kelvyn Jones
Slides only: Global variations in health and mortality (PowerPoint, 1.3 mb)
Modelling Social and Educational Segregation (voice-over with video and slides, to view this presentation you will require Internet Explorer and Flash player plugin)
presented by Harvey Goldstein
Slides only: Modelling social and educational segregation (PowerPoint, 0.1 mb)
Audio presentations
- School league tables: what can they really tell us?
- Listen to part of the programme 'The Learning Curve' (mp3, 4.2 mb) broadcast by BBC Radio 4 on 6-Jun-08
- Or download ogg file (ogg, 3.0 mb) or
- Or listen to the complete BBC programme. School league tables are eagerly scanned by parents hoping to find the best school for their child, and by teachers hoping to see their school rise in the rankings. But do they tell parents what they need to know? Harvey Goldstein and George Leckie argue that league tables are not fit for that purpose, and say it is time that their publication should cease. (Download full article from Wiley Online Library)
- Top of the Class:
- Listen to More or Less (Realplayer, 4.4 mb, to download this media player go to http://uk.real.com/realplayer/) broadcast by BBC Radio 4 on 11-Dec-06, featuring: Harvey Goldstein. For nearly 15 years, the league table, and its raw material, performance assessment, has been the driving force behind policy; and nowhere more so than in education. In the beginning, it seemed simple: tell parents how good the local school is. But, as Andrew Dilnot discovered, that ambition began an enduring clash of political will with statistical headache. We have steadily learnt over the years, and through repeated reform, how hard to achieve that simple objective is.
Note: some of the documents on this page are in PDF format. In order to view a PDF you will need Adobe Acrobat Reader
Please note some of these films require the Flash player plugin.
There is a variety of software you can use to unzip files, e.g. WinZip or CAM unZip.
If you experience problems accessing any videos, please email info-cmm@bristol.ac.uk.