Keeping in mind that we're looking at an information channel with information coming in, information being transmitted, and information coming out, there are two ways in which all of this could screw up. Noise. Output information would not be identical with the input information. Another way: lose information at the source.

DIAGRAM: Venn Diagram Model of Information Transmission.

We've got:

- stimulus information - response information

Red area shows information in both. The larger the area, the better everything is. More of what's in the input is getting through the output. Anything that's in the output that's not in the red area is in this area, and that represents the noise. Anything that's in the blue circle that's not in the red area represents information that's lost. We can look at the total amount of the information by looking at the union.

H(X/Y) - H of X given Y - equivocation H(Y/X) - H of Y given X - noise

I don't like when you use the word "memorizing", because it's almost nothing.

Only thing you'll probably memorize is the weighted sum of the log of probabilities.

You don't need to memorize anything because the formulae come directly from the diagram.

Matrix of stimulus and response. Once they get off the diagonal, then they're making errors.

DIAGRAM: Contingency table representation of experimental data

P(x_i) = n_i / N p(x_i, y_j) = n_ij / N

Interesting: Objective probability. Some of the time, you may have to think about the probabilities in your source.

If the dispersion is large, then the intersection is small.

IF YOU ARE CONSISTENT, IT'S POSSIBLE TO COMMUNICATE. Weakness of approach: Mathematically, we could have everyone saying Yes instead of No and No instead of Yes, and have everyone live normally. In human terms, we would have to adapt to that.

DIAGRAM: Fundaments of models of the human operator as a limited information channel

Uses a Mac.

- Humans in a control loop. Anesthetist controls the system.

- Very complex system controlled there. Bringing live human being to

the threshold of death.

- More complicated now. Quality control. Quality of outcome. As few

side effects as possible.

- Will be able to ask questions - Going to Western.

- Teaching hospital, so you have residents doing all the work. chief

surgeon, etc. watching over the residents. You can talk to them.

- Get some sense of the interaction between these guys. Training

expertise is also an issue that's part of this course. first-hand example of one expert training another expert.

- sensory input: visual and audio - trying to sort out what's important and what's not. prioritize. attention - driver's doing some prediction - comprehension and planning (ex: black ice ahead, must think of detours) - memory processing going on - decision-making: different options of what you're going to do - motor control. manual control is the result of decisions. needs information processing as well.

- Simplest model - I make a noise, nobody's expecting it, you get startled, and jump. - Information comes in as external stimuli - Cognition to figure out what it is - Response - Really basic model. Tells us what we already know. Not much new insight.

- Human: Perceived information - Human: Information processing and decision making - Human: Motor responses for control activation - Human-machine interfacez - Machine: Control devices - Machine: System - Machine: displays

The system could be anything: hardware, software, peopleware.

The human's effectors control that system or influence that system through different mechanisms. Steering wheel, gas pedal, joystick, keyboard, whatever. You can't control the system unless you have some kind of feedback. Displays are not just visual; they can also be auditory or other stuff. For example, a flight simulator, a motion simulator, etc.

This is a generic model. It doesn't give us a lot of insight.

We'll be seeing this model over and over. This is what drives the course.

Model: representation. There are toher ways of representing such a complex system. this is the one that's proposed by the authors of your textbook. The authors of your textbook are Chris Wickens and Justin Hollands. Chris Wickens just retired this year. Aviation lab, human factors department, Illinois. Huge HF factory down there, very very well known. He lives in Toronto, he works at defense R&D. Guest lecturer next Tuesday!! We really have to admt that this is Chris Wickens' model because he had it before Justin coauthored.

Added SCR framework there just to show that even if there are different models, they have something to do with each other. In general, when we look at the left side, we're looking at sensing. center: cognition. r: response.

psychological model, not an engineering kind of model. If any of you have taken control engineering, then there's a different kind of a focus: mathematical, formulae, equations. here, the focus is not on quantitative representations, but functional representations. human information processing functions. you can't make a plot of the different control groups. nevertheless, psychological model, recognizes most basic concept of control engineering: feedback.

wwen we talk about inputs, we're talking about sensing: receiving information. what do we do when we sense something? you are probably sensing your elbow on your desk right now, but it doesn't mean anything to you... if somebody were to be touching you from behind, you would first detect it, and then you decide whether or not it means something: identifying. coding and classifying. different kinds of input tasks.

cognition: thinking about. making decisions, manipulating, solving problems, planning ahead, things like that.

effect something, influence environment...

categories of errors you could be making. NOTE: Diagram. Output: Chaining: sequential chaining effects?

Model itself. STSS: Short-term sensory storage. BIG DEAL. One insight is that we've got many arrows going from going into processing. We are continually assaulted by many kinds of sensory input, but it's only the important ones that make their way fthrough our IP system. we have stuff coming in whether we like it or not. you could be receiving information without perceiving it. All sorts of stuff coming in whether you like it or not. Cognitive work. Boundaries are vague as you get toward the center. Perceive information. You identify it's there, you start attributing meaning to it.

Working memory, cognition: CPU. This is where all the work goes on. Arrows down to one.

Attentional resources. This model is telling us that hovering abve all of this SCR is attention. It's your attentional capabilities which determine what you're going to attend to (obvious) because you're limited. You can't do many many things at onece. tHat's the primary theme of the course. We are limited by the amount of information and the rate at which we can process information.

Arrow from attention rsources to our sensory processes as we select whilat we perceive. over here (STSS( we have no arrows. an interesting message from this is that there are information processes that are going on athat are pre-attentive. You take them in even if you're not consciously trying to. You can't process information unless you understand what it means. You have to have long-term memory. If you're reading a book in Armenian, but if the words don't mean anything to you, you can't process the book.

Long-term memory: storage. You can't do anything with your CPU unless you have RAM: working memory. Computation, translations, comparisons, etc.

And your attentional resources affect whether you're going to attend to something. Which of the many things you're going to attend to, whether you're going to attend to, how you put your priorities in your working memory, it's going to influence your long-term memory, deciding what to put in your long-term memory. long-deciding what to store for later. You're going to respond. Selectingi: I(A lot through eyes and head motion for communication). Have to execute that. So if I start stumbling over words, then having problems in haining and inserting and misordering in terms of response execution. Declining in performance in total information processd.

I'll be bringing this back during the course to show whow what we're talking about relates to the model.

Chatpure 1: Stuff about history not covered because most people have heard it before, but should read anyway.

Modeling the human as an information processing channel: information theoretic models.

We're going to look at more global models. The first part of the course is more quantiative than the first part of the course. We're going to look at actual quantitative modeling, all of which is concentrated in chapter 2. Chapter 2 talkes about information theory and signal detection theroy. comm engg should have an easier time with this. the rest haven't, so i spend an inordinate amount of time trying to explain it slowly.

information theory models. can we quantitatively model or characterize, typify human information processing. Yes, for some tasks. Let's look at what that means.

First: human as information processing channel / system. Quantifying. hat do we mean about quantifying informaiton.

The basic principle of modeling a human operator: the human operator is a LIMITED CAPACITY NOISY COMMUNICATION SYSTEM.Limit to amount of information we can absorb. Limit to rate of absorbing information. We are noisy because there are imperfections in our ability to perceive visual, auditory information. We are a communication systems is the sense of having different kinds of input and we're trying to match the outputs to the inputs. We're trying to influence our environment in accordance to the information coming in. Which is what we do when we're faced with the stovetop burners. Input: which one. Output: action.

• Reduction: Internet searching, summarizing. for example, what you're doing what now.
• Trasmission: If you're copying down everything I'm showing you, that's a transmission task. If you're transcribing written text into typed text...
• Elaboration: Example: 3000 word essay on my shirt. Efforts to show the same kind of information theory modeling for just the physical information processing in our body. The message here is the size. At the sense organs, you get 1 gigabit/s. Nerve junctions: 3 megabits. Conscious awareness: 16 bits. Lasting impression: 0.7 bits / second. _ Check out these numbers to see if they make sense What's important: less than one bit per second. goldfish 7 seconds, every time it swims around the bowl, it's seeing things for the first time