Topic 4 - Ergonomics (Human Factors) Flashcards
What study did Brown and Baulton conduct in 1961?
Participants drove in either a residential area or a crowded shopping centre car park while listening to a tape of numbers
What were the two driving environments used in the Brown and Baulton study?
- Residential area - few inputs
- Crowded shopping centre car park - large numver of important inouts
In which driving environment did participants make more errors?
Shopping centre car park
What task were participants required to perform while driving?
Identify changed numbers from a sequence
What conclusion can be drawn about attention from the study?
Participants needed to give more attention to driving, leaving less mental capacity for the number task
Brown and Baulton’s study exemplifies which concept?
Secondary task performance
Fill in the blank: Participants made more errors in the _______ than in the residential area.
shopping centre car park
What was the method of Brown and Baulton’s study?
Participants drove in either:
A residential area - few important inputs
A car park of a crowded shopping centre - large number of important inputs
While doing this they were played a tape containing lists of numbers
They had to identify what numbers changed from one sequence to the next
What were the results of Brown and Baulton’s study?
Participants made more errors in the shopping centre car park than the residential area
Participants needed to give more attention to the stimuli associated with their primary task of driving so had less mental capacity left over for the stimuli associated with the less important number task
This is an example of secondary task performance
What was the Hawthorne studies?
Study carried out in the Hawthorne plane in Chicago in the 1920s
Mayo was investigating effects of the physical environment on productivity levels
Initially they varied light levels for the experimental group and kept the same level for the control group and found that both improved in terms of productivity
Level of light didn’t matter - bright or dull experimental group improved
All changes they made caused an increase in productivity
Explain the conclusions of the Hawthorne studies:
Popular interpretation is that it was the novelty of the situation and fhe fact that the workers knew they were being observed that caused the increase in production
This became known as “The Hawthorne Effect”
Humans performance improves when they know they are being observed
What was the method of Stones study:
Stone studied whether ability to study is affected by:
The setting - open plan or private
Colour of the room - blue white or red
Type of task - reading or maths
144 students assigned to 1 of 12 condition from the combination of colour, setting and task
They were asked to complete a questionnaire that measured mood, satisfaction and motivation
What were the findings of Stones study in an open plan room?
Most positive mood in the blue open plan room
Least positive mood in the red open plan room
Most satisfaction with performance in blue open plan room
What were the findings of Stones study in a private room?
Red brought the most positive mood in private room
Most satisfaction with performance in white private room
What were the overall findings in Stones study?
Little difference in privacy between open plan and private room
Participants performed worse in reading task irrespective of setting if in a red room but better if in a white room
What was the aim of Drews and Doig’s study?
Develop a configural vital signs display to help ICU nurses in the faster detection of physiological changes through graphical data displays and not just numerical displays
What was the sample of Drews and Doig study?
42 nurses (21 nurses per condition)
69% female
All had at least a year of experience in intensive care units
What was the method of Drews and Doig study?
Laboratory experiment - at a university
The study presented each participant with four different scenarios (e.g. septic shock)
participants had to use whichever displays they were given to diagnose the patients in the scenarios in 5 minutes
One group used a traditional ICU numerical display
Other group used the CVS graphical display and this included trend data
For the CVS display shapes & colours were used to increase the speed at which information could be processed
The researchers measured response time and diagnosis accuracy.
What were the results of Drews and Doig’s study?
Participants using the CVS display diagnosed the patients 48% quicker in the septic shock scenario and 38% quicker in the pulmonary embolism scenario
Accuracy of the CVS group was also a third higher than the other group and they reported lower mental demand using it
What was the conclusion of Drews and Doig’s study?
CVS displays are superior to the traditional ICU displays but that further testing and research will need to be done to develop their investigations
What is the magic number proposed by Miller for short term memory?
Miller proposed the magic number 7 plus or minus 2, meaning most people can remember between 5 and 9 pieces of information in their short term memory.
What technique is referred to as the digit span technique?
The digit span technique refers to the method of measuring the limits of short term memory as proposed by Miller.
What happens to information in short term memory if rehearsal is prevented?
If rehearsal is prevented, information can vanish from short term memory in a few seconds.
How can we increase the amount of information held in short term memory?
We can increase the amount of information in short term memory by chunking or grouping items into larger chunks.
What makes chunking more effective?
Chunking can be even more effective if the chunks have meaning.
