Class 6 EMTM 601 Gregg Vesonder University of Pennsylvania Penn Engineering - Computer & Information Science ©2013 Gregg Vesonder 1 Roadmap • Finish Lecture 5 • On Programmers • Clouds • Light Weight Methodologies • Open Source Software • Brooks in Summary • Reliability, Fault Tolerance, Trustworthy Systems • Software Archeology • Outsourcing • Best Practices -> Default Good Practices • $1000 viewgraph(s) • Take Home Final • Reading this session: S Chapter 3, 11 & 12, finish Brooks 2 Log Book • The Monkey and the Elephant • Yours? 3 TQM 4 ISO Quality System • ISO set up a series of standards for quality management • ISO 9001 most suited for software - model for quality assurance in design, development, production, installation and servicing • ISO 9004-1 contains guidelines for individual elements of various standards • ISO 9000 process includes third party auditor, with audits every 6 months and reregistration every 3 years - expensive • Necessary for some customers 5 Software Quality Assurance • Basic idea: improve quality by monitoring software and its development process – Ensure compliance with established standards – Ensure that inadequacies are brought to the managements attention and fixed – They review and audit and must be separate from production – Support of management, have go/no go authority – Must be technically competent • IEEE 730 provides a framework for Quality Assurance plan • IEEE 983 is a complement to 730 and offers further guidelines including implementation, evaluation and modification. 6 NSA and Assurance • Brian Snow - http://www.acsa-admin.org/2005/papers/Snow.pdf • Some highlights – Very strong use of formal methods, SEI level 5,TSP and PSP – Mutual suspicion – modules auditing and alarming each other’s behavior – same with developers! • Hardware assist, e.g, isolated processor and address space for assured operations • Third party testing and certification programs • A flavor: “No single component, module, or person knows enough about the overall transaction processing system to be able to mount a successful attack …” 7 Reality Check • The business is software, danger of a shift from developing software to developing processes, but … • Quality is recognizable 8 Pirsig • Zen and the Art of Motorcycle Maintenance: An Inquiry Into Human Values, Bantam Books, 1974. ISBN:0-535-27747-2 What I (and everybody else) mean by the word quality cannot be broken down into subjects and predicates[…]If quality exists in an object, then you must explain why scientific instruments are unable to detect it[…]On the other hand, if quality is subjective, existing only [in the eye of] the observer, then this Quality is just a fancy name for whatever you’d like […] Quality is not objective. It does not reside in the material world[…] Quality is not subjective. It does not reside merely in the mind. – Robert Pirsig 9 Software Factories • Applying factory techniques to software development emphasizing process, measurement and reuse (Toshiba’s view) • Software Workbench - integrated environment that supports all workers in factory - includes programming, debugging, configuration, test, requirements, documentation. Project management, quality assurance and reuse • Uses waterfall model • Project is divided into unit workloads with daily and weekly status, tracking actual vs expected, provides feedback and identifies issues • Heavy Quality emphasis • Reuse is the single most critical issue in improving quality and productivity • Quality circles - voluntary groups of works that focus on improving quality, process, … 10 Our Context • User Experience Design is neither linear nor rigid! HCI Overview • Motivation for HCI the Benefits • Definition of HCI • Current view of Cognitive Science • User Centered Design • Evaluation • Heuristics Lecture 5! 12 Why spend effort on the UI? • Increased efficiency • Improved productivity • Reduced errors • Reduced training - strive for game like training • Improved acceptance 13 Definition • This definition emphasizes the benefits • US Military Standard for Human Engineering Design Criteria (1999): – Achieve required performance by operator, control and maintenance personnel – Minimize skill and personnel requirements and training time – Achieve require reliability of personnel-equipment/software combinations – Foster design standardization w/in and among systems 14 Yet Another Definition • But then there are other approaches and motivations • Raskin: An interface is humane if it is responsive to human needs and considerate of human frailties – Boot up - that the user should not be kept waiting unnecessarily is an obvious and humane design principle • Note recent efforts to improve – Users should set the pace of interaction – Windows - hitting start to shutdown • Asimov paraphrase: “A computer shall not harm your work or, through inaction, allow your work to come to harm” • A computer should not waste your time or require you to do more work than is strictly necessary 15 Asimov’s Laws of Robotics • (A soon to be recurring motif that the best interface may be none, with precautions) • 0. A robot may not injure a humanity or, through inaction, allow humanity to come to harm. • 1. A robot may not injure a human being or, through inaction, allow a human being to come to harm, except where that would conflict with the Zeroth Law. • (old 1. A robot may not injure a human being or, through inaction, allow a human being to come to harm.) • 2. A robot must obey orders given it by human beings except where such orders would conflict with the First Law. • 3. A robot must protect its own existence as long as such protection does not conflict with the First or Second Law. 16 Approach to UI • So how do we get there? • The user interface is the system to the user- not a novel approach, also known as User Centered Design – Cognitive sciences (including “humanities”) * – Artistic Design – Ergonomics * • User Interface is the point of view of the user! Includes hardware and software. Most modern view is USER EXPERIENCE • Do not separate design of functionality from design of interface - remember “User manual first” (combines functionality and interface) attitude to interface development • Overlearning is powerful - sometimes RPN is the right thing! • Mental model (desktop) vs. conceptual model/design model - have to be closely related • First a bit about ourselves 17 The Human Information Processing System - INPUT Atkinson and Shiffrin Sensory Store Short Term Memory Repetition Displacement/ Decay Decay/ Displacement Long Term Memory Interference 18 Conscious vs. Unconscious (from Raskin, 2000) PROPERTY CONSCIOUS UNCONSCIOUS Engaged by Novelty, Emergencies, Danger Repetition, Expected events, Safety Used in New circumstances Routine situations Can handle Decisions Non-branching tasks Accepts Logical propositions Logic or inconsistencies Operates Sequentially Simultaneously Controls Volition(free will) Habits Capacity Tiny Huge Persists for 10ths of seconds Decades (lifelong?) Conscious ≈ STM, Unconscious ≈ LTM 19 Saturated Yet? 20 Stroop Test Interference between the memory systems What color are the words? 21 Stroop 2 22 Psychological principles • Working memory (STM) is only around 5 - auditory tasks depend on working memory • Long Term Memory is slow and things may be available but not accessible - multiple coherent cues make it easier • Attention can be overloaded and depends on the state of the individual • Recognition is easier than recall • Remember issues of Just Noticeable Differences, JNDs • Expert Novice distinctions are a factor in enjoyment of the system 23 More Principles • Humans receive more information through visual system and store it spatially -- mental rotation studies, the more rotation, the longer to respond • Humans tend to structure what they see to form cohesive patterns -- 5 Gestalt laws: – Proximity - we tend to group things together that are close together in space – Simularity - we tend to group things together that are similar – Continuation - we tend to perceive things in good form – Closure - we tend to make our experience as complete as possible – Figure and ground - we tend to organize our perception by distinguishing between a figure and a background 24 Proximity Thanks to Psy280 notes from Toronto! 25 Continuation http://peace.saumag.edu/faculty/kardas/courses/ 26 GPWeiten/C4SandP/continuity.GIF Figure - Ground 27 Maslow’s PYRAMID Needs needed SELF to be met - ACTUALIZATION ideas for reinforcers, Self esteem needs given situation Love & belonging needs Safety & security needs Basic physiological needs 28 Still More Principles • Multimodal information is easier to use than single mode (text + image + sound) increasing the richness of memory -- similar to mnemonic tricks such as the method of loci – “depth” of processing • From theory to practice, onto Design 29 PAR • Is your experience up to PAR? • Perception • Attention • Retention © 2010 Gregg Vesonder Knowledge in the World and in the Head DESIGN MODEL USER’S MODEL DESIGNER USER SYSTEM IMAGE •Gulf of execution - mismatch between users intention and allowable actions “the user and the designer •Gulf of evaluation - mismatch communicate only through the SYSTEM between systems representation system itself” and user’s expectations 31 Task Analysis • Analyze task within context of use: – The users – The tasks – The equipment (hardware, software, materials) – The social environment – The physical environment 32 The Users: Groupings -1 • Pre school • Grade school • Middle/High School • College to Post Grad • Adult - business