Reading Room Material: Luke Cage & Expertise

Editorial Note: One of the goals for my blog is to connect educators with Cognitive Science. To make that connection, I try bring in real-world examples. I've been mildly successful in doing so, but I feel like there's something missing. I feel like there's more I can do. 

With today's post, I am going to start publishing a new type of blog called Reading Room Material. The goal is to share examples of Cognitive Science from the outside world. The focus isn't necessarily to define a technical term from the field, like my traditional posts. Instead, the goal is to connect Cognitive Science to our daily lives. 

Luke Cage: Season 1, Episode 2 "Code of the Streets"

Luke Cage is a Netflix television show that's based on a Marvel comic. The titular character works at a barbershop, and it is owned by a man everyone lovingly refers to as, "Pop." Like barbershops of old, Pop offers a straight-razor shave. Cornell Stokes (a.k.a. "Cottonmouth") is one of Pop's oldest associates; however, he has somewhat lost his way. 

In this particular episode, Cornell comes in for a shave so he can chat with Pop about a missing person. Here's a snippet of their dialog [1]: 

Stokes: The clippers are idiot-proof. That's what's missin' nowadays, Pop. Attention to detail. Everyone wants things fast, quick. Me? I like to take my time.
Pop: Time is a luxury most working class men cannot afford.
Stokes: True. Time is precious. Shouldn't be wasted. Mmm A good razor shave is like a vacation to me. It's incredible how few people take advantage.
Pop: It's a lost art.
Stokes: Exactly. That's the problem with these youngsters. They want it all. But they don't want to put in the work. They'll rob lie, cheat, steal, just to get what they want. Damn shame if you ask me.
Pop: Yeah.
Stokes: Shame.
Pop: Mmm-hmm.

There's definitely some subtext here. So what are they really talking about? Some may disagree, but what I think they're really talking about is deliberate practice [2]. Students just aren't willing to put in the 10,000 hours of deliberate practice to become experts! Moreover, the vanguard seem to lament that fact. 

Whether a person is a gangester or a violinist, they have to put in the time. There is no free lunch when it comes to expertise!


Share and Enjoy!

Dr. Bob

More Material

[1] Here is the full transcript of the episode.

[2] Ericsson, A., & Pool, R. (2016). Peak: Secrets from the New Science of Expertise. Houghton Mifflin Harcourt.

The Downside of Expertise: Part 2

Editorial Note: This is the second installment of The Downside of Expertise. In Part 1, we introduced the idea that experts can get stuck in a rut. They have a hard time ignoring their expertise when it comes to things riding a bike, swinging at a pitch, or generating creative solutions to a problem. In Part 2, we explore how this line of research got started, and how it might connect to education. Go find your chessboard, and we'll get started! 

Check and Mate!

As it turns out, much of what we know about expertise began with studying those who play chess — a lot of chess. To simulate the methodology that the early studies used, let's start with two chessboards. For one of the boards, we've caught the players in the middle of a game. For the other board, the pieces are scattered randomly about the board. Can you tell which board is an actual game and which one is random [1]?

Chessboard A

Chessboard B

Now that we've determined which board is which, what if I asked you to memorize the configuration of the pieces on the board? Do you think you could do it? How long would you have to study the board until you memorized all of the pieces? How many pieces do you think you could get right after studying the board for one minute?

Let's up the ante one more time. Suppose that we pitted your board memorization skills against a chess master. Amazingly, a master can reproduce an entire chessboard in about 5 seconds [2]. In a controlled laboratory experiment, scientists compared asked a chess master, a class A player, and a chess novice to memorize a mid-game or randomly scattered board [3]. For a mid-game board, the chess master was able to remember more pieces than either the class A player or the novice. He was able to memorize the spatial configuration of approximately 25 pieces because he was able to chunk them into higher-level patterns of positions one might expect during a chess game. Given what we know about well-developed retrieval structures, the master's performance comes as no surprise. 

But how did the chess expert fair with the random board? As it turns out, his performance was reduced to a novice, despite the fact that he had an extremely elaborate schema for chess positions. Because the positions didn't make any sense in the random configuration, he was forced to fall back to brute-force memorization, which carries with it all of the standard limitations of working memory. In fact, the novice slightly outperformed him!

The same principle of expertise holds for chess masters and Major League Baseball batters: Expertise is highly narrow. Once you depart from the patterns that experts expect, they perform at novice levels.

The STEM Connection

There are definite downsides to expertise when the situation completely violates an expert's deeply engrained schema or mental model. But what, if any, are the downsides for education? A master teacher is an expert in a particular content area (e.g., how to solve algebraic problems) and owns a vast repertoire of pedagogical content knowledge (e.g., how to teach algebra). 

Like the creativity study, can content knowledge get in the way of teaching? One way that it might be harmful is when teachers forget what it is like not to know something. Or, stated differently, experts might not remember the developmental sequence that a student must undergo when learning something new. When this forgetting takes place, educational researchers call it the expert blindspot.

In a series of studies [4-6], Mitch Nathan and his collaborators demonstrated the conditions under which expert teachers are blinded by their expertise. They asked teachers with different levels of content knowledge to rank-order six math problems that varied along two dimensions. For the first dimension, the unknown (x) was placed either at the beginning (e.g., x • a + b = c) or the end (e.g., [c - b]/a = x) of the problem. The start-unknown problems were essentially algebraic problems because the student had to apply the inverse of the operators to compute the unknown value. The end-unknown problems were essentially arithmetic problems because they could be solved by applying each operator in the prescribed order. 

For the second dimension, problems were stated either symbolically (e.g., x • 6 + 66 = 81.90), as a word equation (e.g., "Starting with some number, if I multiply it by 6 and then add 66, I get 81.90. What did I start with?"), or as a story problem (e.g., "When Ted got home from his waiter job, he multiplied his hourly wage by the 6 hours he worked that day. Then he added the $66 he made in tips and found he earned $81.90. How much per hour did Ted make?"). Take a moment to figure out which problems you think are the most difficult:

1. Start-unknown; story problem
2. Start-unknown; word equation
3. Start-unknown; symbolic equation
4. End-unknown; story problem
5. End-unknown; word equation
6. End-unknown; symbolic equation

All teachers agreed that the end-unknown problems were easy because they basically tell the student what to do. The surprising result was that students found the verbal problems (i.e., the story problem and word equation) to be easier than the symbolic equation for the start-unknown problems. The reason why is that the format of these problems prompted students to fall back onto various problem-solving patterns that were logic-based. In other words, students have been reasoning verbally for much longer than they have symbolically, and this became evident when they were faced with challenging, algebraic problems. 

Expertise is typically a great thing to aspire to, and I highly recommend it. So I don't want to give the impression that you should avoid becoming an expert. But I do want to make explicit some of the misconceptions that people might have about what experts can and can't do. As the authors of Freakonomics are fond of saying, there's a "hidden side to everything" [7]. For expertise, the hidden side is a difficulty in suppressing one's own expertise.


Share and Enjoy!

Dr. Bob

For More Information

[1] Chessboard A is an actual mid-game; whereas Chessboard B is a random assortment of pieces. There are multiple ways to figure it out, but one piece of evidence is that there are two black bishops on the same colored squares, which can never happen in an actual game.

[2] de Groot, A. D. Thought and choice in chess. The Hague: Mouton, 1965. 

[3] Chase, W. G., & Simon, H. A. (1973). Perception in chess. Cognitive psychology, 4(1), 55-81.

[4] Nathan, M. J., & Koedinger, K. R. (2000). An investigation of teachers' beliefs of students' algebra development. Cognition and Instruction, 18(2), 209-237.

[5] Nathan, M. J., & Koedinger, K. R. (2000). Teachers' and researchers' beliefs about the development of algebraic reasoning. Journal for Research in Mathematics Education, 168-190.

[6] Nathan, M. J., & Petrosino, A. (2003). Expert blind spot among preservice teachers. American Educational Research Journal, 40(4), 905-928.

[7] Dubner, S. J., & Levitt, S. D. (2010). Freakonomics: A Rogue Economist Explores the Hidden Side of Everything. HarperCollins.

The Downside of Expertise: Part 1

Editorial Note: I am so excited about the next topic that I had to split it across two posts. For Part 1, I introduce the idea that, while expertise is great, there is a cost associated with it. In Part 2, I will talk about the origin of research on expertise and its educational implications. Let's jump in with a real mind scrambler!

The Backwards Brain Bicycle 

Grab a junky bike and pull the handlebars and stem out of the steerer tube. Next, weld one gear onto the steerer tube and another gear onto the stem (the stem is the piece connected to the handlebars). Once you're done, it should look like this:

Due to your modification, when you turn the handlebars to the right, the front wheel pivots to the left (and vice versa). Before you embark on your maiden voyage, what do you suppose will happen? If you're not sure, take a look at this fascinating video.

What happened to this poor engineer? Why did it take him eight months to learn how to ride his "backwards brain bicycle"? The answer to that question is related to why a softball pitcher can reliably strike out the best batters from Major League Baseball (MLB).

"Swing and a miss" --Harry Doyle

In MLB, there is a distance of exactly 60.5 feet between the pitcher's mound and home plate. When a pitcher throws a 95 mph fastball, the ball arrives in a little less than half a second (.43 seconds, to be precise). That means the batter needs to decide whether he should swing (or not) in about a quarter of a second. Otherwise, the ball will blow past him as he stands there and ponders whether he should swing. 

Because it truly is a split-second decision, the batter must look for an edge. One place to find an edge is to move upwards in the stream of events and find a reliable cue for swinging. One of the cues that batters use is the pitcher's grip on the ball. If they hold it with two fingers over the top, then it is a fastball. If they put more distance between their forefinger and the thumb, then it will be a curve ball. The other cue that batters look for is the spin on the ball, which transmits itself as a certain "color" of pitch. 

MLB players log thousands of hours behind the plate trying to hone their batting ability. In effect, they become experts in watching, categorizing, and reacting to a variety of different pitches. So if they truly are expert batters, then why can softball pitcher Jennie Finch strike out batting legends Barry Bonds and Albert Pujols? [1]

The explanation is fairly simple. Expertise is highly narrow. When faced with a typical softball pitch, MLB batters are watching for something that will never come. They've essentially wired their brain to perceive and react (without much conscious intervention, mind you) to a highly narrow band of stimuli. Because overhand pitches used in MLB tend to fall, the batter watches for a ball that starts high and gets pulled to the ground. A softball pitcher throws underhand, so the ball starts low and has the possibility of rising. They also are watching for the aforementioned cues of the pitcher's grip and the spin on the ball, but the grip that a softball pitcher uses is completely different. By changing the narrow band of stimuli that a batter is trained to read, you can essentially reduce and expert batter to a novice, or possibly even worse.

But let's stop talking about muscular expertise. What about conceptual expertise? Are there any hidden costs there?

Looking in All the Wrong Places

Another way in which expertise can steer a person wrong is by biasing her to look for solutions within the prescribed content area of her specialty. Consider the following experiment [2] where baseball experts were given a creativity test called the Remote Associates Test (RAT). Their job was to look at a list of three words and figure out what single word binds them together. There were multiple experiments and conditions in the original study, but the one relevant to the current discussion was between lists of words where the domain knowledge was relevant and applicable and a different list of words where the domain knowledge was irrelevant and misleading. 

To make this concrete, suppose you are a baseball expert, and I give you the following three words: 

Baseball-Relevant:     WILD     DARK       FORK

What word connects these three? A baseball expert might answer PITCH (e.g., wild pitch, pitch dark, and pitch fork). The word "pitch" comes straight out of baseball, and it is therefore relevant to the solution to this RAT problem. When solving baseball-relevant problems, baseball experts had an accuracy rate of about 38%. This was roughly the same accuracy rate among baseball novices, who identified the connecting word 40% of the time.

But then the experimenters switched things up and gave baseball experts and novices a list of words that seemed like they might be connected to baseball, but ultimately they were not connected. Here is an example: 

Baseball-Irrelevant:     PLATE     BROKEN       SHOT 

What single word connects these three [3]? The first two words seem to hint at HOME (e.g., home plate and broken home), but then HOME doesn't really go with the last word (what is a home shot or a shot home?). How do you think the experts did? Their performance plummeted. Their accuracy rate dropped by over half, to 15%. Baseball novices didn't show the same drop in their performance; in fact, they showed the same accuracy rate of 40% on the baseball-relevant and irrelevant tasks. 

What's going on? Why can't baseball experts suppress their knowledge? Even when the experimenters warned them that baseball knowledge was irrelevant, they still couldn't turn it off. They seemed to be biased towards looking for solutions that are aligned with topics that they know a lot about, which actually interfered with performance when the solution was not aligned with their area of expertise. What may also be surprising is that the experts, at least for this task, did not out-perform their novice counterparts. In my next post I will explore situations in which being an expert can help, or hinder, performance, depending on the task at hand.

That concludes Part 1 of The Downside of Expertise. Check back next week for the conclusion and the connection to education!

Share and Enjoy!

Dr. Bob

For More Information

[1] Why MLB hitters can't hit Jennie Finch and science behind reaction time. Sports Illustrated, Volume 119, Issue 4. (July 29, 2014) [link] [video]

[2] Wiley, J. (1998). Expertise as mental set: The effects of domain knowledge in creative problem solving. Memory & Cognition, 26 (4) 716-730.

[3] The word that binds PLATE, BROKEN, SHOT together is GLASS.