Human Sciences, Statistics, and R

January 6, 2013

The use of statistics has long been important in the human sciences. An early example is an analysis by William Sealy Gosset (alias “Student”) of biometric data obtained by Scotland Yard around 1900. The heights of 3,000 male criminals fit a bell curve almost perfectly:


Histogram © A. H. Dekker, produced using R software

Standard statistical methods allow the identification of correlations, which mark possible causal links:


XKCD teaches us that “Correlation doesn’t imply causation, but it does waggle its eyebrows suggestively and gesture furtively while mouthing ‘look over there.’”

Newer, more sophisticated statistical methods allow the exploration of time series and spatial data. For example, this project looks at the spatial distribution of West Nile virus (WNV) – which disease clusters are significant, and which are merely tragic coincidence:


Distribution of significant clusters of human WNV in the Chicago region, from Ruiz et al.

SPSS has been the mainstay of statistical analysis in the human sciences, but many newer techniques are better supported in the free R toolkit. For example, this paper discusses detecting significant clusters of diseases using R. The New York Times has commented on R’s growing popularity, and James Holland Jones points out that R is used by the majority of academic statisticians (and hence includes the newest developments in statistics), R has good help resources, and R makes really cool graphics.


A really cool graph in R, using the ggplot2 R package (from Jeromy Anglim’s Psychology and Statistics Blog)

An increasing quantity of human-science-related instructional material is available in R, including:

Through the igraph, sna, and other packages (and the statnet suite), R also provides easy-to-use facilities for social network analysis, a topic dear to my heart. For example, the following code defines the valued centrality measure proposed in this paper:

library("igraph")
valued.centrality <- function (g) {
  recip <- function (x) if (x == 0) 0 else 1/x
  f <- function (r) sum(sapply(r, recip)) / (length(r) - 1)
  apply (shortest.paths(g), MARGIN=1, f)
}

This definition has the advantage of allowing disconnected network components, so that we can use these centrality scores to add colour to a standard plot (using the igraph package within R):


Social network diagram, produced using R software, coloured using centrality scores

– Tony

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Lollies or Poison

October 16, 2012

Human factors covers many facets of human behaviour and interaction with the natural and constructed environment.  The issue of how to ensure that these environments remain safe for the younger and older members of our society is a case in point.Post image for Product Confusability: Tide Pods

Recently, a dishwashing detergent was packaged so that even adults could easily mistake them for food.  Young children have ingested these dangerous chemicals as the packaging is very colourful and resemble candy or lollies.  The harm done to these children and the increasing toll on the health system would surely outweigh the financial benefit to the manufacturer of this product, who obviously either didn’t think or was blissfully unaware of the consequences.  Perhaps the unwanted publicity of the dangers of this product, especially if there is an impact on their bottom line, may encourage them to design their products with more care in future.

All too often, human behaviour is not taken into account in the design of products.  No amount of urging customers to “be careful” will eliminate the danger posed by badly designed or labelled goods.  It is better business to design them properly in the first place.

When I was involved in training service and police dogs, there were five principles which used to guide us.  Firstly, Knowledge was required – if you didn’t know what you were doing, it made it difficult for the canine to know what was required.  Secondly, Repetition showed the required behaviour.  Thirdly, Patience in attaining the goal was essential.  Praise and Correction were the final principles, the former being more desirable and effective.  It seems that in the case of the design of the products described above, the first fundamental principle was lacking, as is commonly the case in many other applications where the knowledge and expertise of the human scientist is not sought or ignored.

This translates to the whole range of human applications.  Human scientists can provide critical knowledge but this fact is not often understood and can have great impact, both in terms of time and budget when ill informed decisions are made, and especially when the younger and older members of society are involved.

As has been previously posted, the initial BMW iDrive was a product which was installed in vehicles that the older demographic was more likely to acquire, which compounded the problems of poor initial design.  The older drivers did not have the digital savvy or knowledge that their offspring or grandchildren had and therefore the whole concept was flawed from the outset as it did not take into account the basic metrics of the human operator.  Of the five principles that I listed above, Patience is in short supply when you are battling traffic!

Which leads to the point made by the authors of the pieces – consideration of the special needs of the younger and older demographic is central to good design and outcomes going forward.


The future world of neuroscience

October 3, 2012

English: Drawing of the human brain, from the ...

Just read a post on the increasing ability of neuroscientists to image and understand the brain.  The author, Kathleen Taylor makes a very interesting observation that perhaps in the future the research of the brain will surpass the physical sciences in importance.  She is probably biased given her neuroscience background but I feel that she has highlighted some fundamental questions with regard to how humans will interact with the world (or perhaps the universe?) and with each other in the future.

She makes the point that the physical sciences have largely been insulated from how the knowledge gained from research in this area is used, given that there is no human input into their experimentation.  The research is largely introspective or governed by mathematics or similarly prescriptive methods.  The potential consequences of the research is not addressed at any time (at least in a formal sense) as there is little input from others apart from peers and supervisors with a similar research background.

The difference between the physical and social sciences has been commented on in previous blog posts.  Physical scientists, although brilliant in their own field, tend to make assumptions as to how humans fit into their models and how their research can be applied.  Human behaviour is commonly included as a probability which then influences the remainder of the postulated model to provide results which do not necessarily reflect what actually happens in the real world.  However, either these discrepancies are ignored, or assumed to be just part of a distribution of human behaviour.  A system is then designed using such flawed thinking and typically, it is the poor old human operators who have to adapt and make up for such sloppy design when they have to make things work.

Alternatively, these operators are seen as the problem when the system is subsequently audited as the ‘brilliant’ system design is hardly ever tested and/or seen to be at fault.  At last there are glimmers of hope as safety management systems are identifying that these ‘brilliant’ systems are more often than not the cause of many failings, not just from the operator perspective.  So the ‘human error‘ which historically has almost always been attributed as the cause of an accident is sheeted home to where it belonArachnoidgs in the first place – the arrogant human who designed the system who was either unaware of or was permitted to ignore the fact that an inherent part of the design process is to understand how the human operator thinks and acts when interfacing with their system.

On the other hand, social scientists and human scientists in particular have a core theme that human behaviour is far more complex and determined by sensory and perceptual aspects initially, then modified by cognitive processes which are also subject to change.  These factors need to be addressed when modelling how a human operates with a machine or amongst themselves to make decisions etc.  As discussed in Kathleen’s article, the brain is such a complex organ and it is subject to a massive range of inputs that we are only now becoming aware of how it works, and how to manipulate it.  Perhaps in the new millennium, neuroscience may have similar advances as occurred in physics (relativity, quantum mechanics and understanding of atomic and sub-atomic structure for example) during the last.

Kathleen highlights that the ethics of operating on the neural and molecular scale within the human brain and the resultant impact it may have on the individual concerned will be a central theme going forward.  This is especially pertinent when entities such as commercial or government interests will be in a position to manipulate these factors and it is therefore something which needs to be addressed well prior to this particular genie escaping the bottle.

Which leads back to KathleEnglish: Computer tomography of human brain, f...en’s major point.  She contends that neuroscience may overtake the physical sciences as the whole consciousness experience will determine how the human species develops into the future.  The social/psychological/physiological sciences understand these aspects and, most importantly, understand the need for an ethical framework when addressing these matters.  So at least we will be better placed than the current situation, where the physical scientists, who have neither of these fundamentals, seem to determine how technology develops and is applied.  Perhaps we will then have a more level research field where social and human scientists are included at the very beginning and can (heaven forbid!) inform how technology is developed and applied to best advantage for the human user who will ultimately directly interact with it.


(Religion) Lost in Space

September 24, 2012
Luna 9 :*Denomination: 2 Forint

Luna 9 :*Denomination: 2 Forint (Photo credit: Wikipedia)

The concept that any future interstellar exploration be free of organised religion has recently been discussed.  Some have expressed the view that religion is toxic for human interaction and cooperation as is evidenced in many unsavoury incidents throughout history and is currently being witnessed with respect to the YouTube video denigrating the prophet Mohammed and subsequent reaction to it.

Humans have many attributes which may be positive or negative depending on the context.  Adaptability and imagination are very valuable human abilities, but these skills are not required nor perhaps desirable in a situation that requires heuristic thinking.  Conversely, applying a flawed or inappropriate heuristic can have disastrous consequences, or prevent a more appropriate paradigm from being developed.

A human will always be influenced in how they act and think by their prior experience. Even the application of the scientific method cannot eliminate these influences. The ability to assess complex data for example can be affected by education, training, aptitude and a host of other factors, which can vary according to the information being assessed.  It probably explains the range of specialities within a discipline, for example, in medicine, physics, chemistry, engineering and psychology.  With regard to future space exploration, the various TV program depictions such as Star Trek portray a range of specialists in the crew, making the assumption that all of these skills will be required to fully comprehend the magnitude and complexity of space.

Given that previous experience or belief systems are an inherent part of the human condition, it seems logical that a religious aspect will also then be represented within the crew of any intergalactic mission if it is to be truly representative of the human species.  And as bigoted or fundamentalist religious views are by definition extreme values within a normal population, it is highly unlikely that these would be represented to any significant statistical level.

With regard to positive and negative attributes, religion has been blamed for many ills, many of which can be justified.  However, religion should also be recognised for its many positive aspects, such as altruistic value systems, beneficence, the intrinsic value of individuals regardless of race, social standing or wealth, the existence and importance of a fundamental natural order and the concept of stewardship and responsible use of resources that then derive from it. Many advances in science were made possible by the religious systems of the time, such as astronomy and mathematics, although some of the authorities subsequently disputed the findings for whatever reason.  Is it so different to what is currently occurring where the evidence supporting climate change is disputed by certain sections within a secular society without any obvious underlying religious philosophical rationale?  It seems that belief systems generally, not just religious ones, are the root cause of disagreement.  This can be beneficial in the search for scientific truth and the progression of understanding – perhaps conflict is a positive human attribute as long as it is confined within an intellectual framework.So the discussion regarding the crew mix for future space exploration missions should expand to include all human experience and belief systems.  Perhaps religion can help unlock the mysteries of the human mind and the continuing quest of the species to explore and understand the universe.  All of which relates back to human science.