Lecture 17

# Greeno 1974 people plan strategy by breaking problem

• Notes
• 63

This preview shows page 59 - 63 out of 63 pages.

Greeno (1974)   People plan strategy by breaking problem into subgoals people paused at points in the problem when they tackled a sub-goal Subgoal advantage subgoal hint: get 3 Orcs across the river no hint = 30 moves with hint = 20 moves sometimes needed to violate the strict difference-reduction strategy

Subscribe to view the full document.

Working Backwards Heuristic: Example
One (painful) way to solve the water lilies problem Initial number of water lilies = 1 double the initial value 90 times Record each of these values Find the value that is 1/2 of the 90th day value. Working backwards: - value doubling every day is equivalent to say that the value is halved each preceding day - the field was full Day 90th - the field was half full on day 89th 1 1 31 1073741824 61 1152921504606850000 2 2 32 2147483648 62 2305843009213690000 3 4 33 4294967296 63 4611686018427390000 4 8 34 8589934592 64 9223372036854780000 5 16 35 17179869184 65 18446744073709600000 6 32 36 34359738368 66 36893488147419100000 7 64 37 68719476736 67 73786976294838200000 8 128 38 137438953472 68 147573952589676000000 9 256 39 274877906944 69 295147905179353000000 10 512 40 549755813888 70 590295810358706000000 11 1024 41 1099511627776 71 1180591620717410000000 12 2048 42 2199023255552 72 2361183241434820000000 13 4096 43 4398046511104 73 4722366482869650000000 14 8192 44 8796093022208 74 9444732965739290000000 15 16384 45 17592186044416 75 18889465931478600000000 16 32768 46 35184372088832 76 37778931862957200000000 17 65536 47 70368744177664 77 75557863725914300000000 18 131072 48 140737488355328 78 151115727451829000000000 19 262144 49 281474976710656 79 302231454903657000000000 20 524288 50 562949953421312 80 604462909807315000000000 21 1048576 51 1125899906842620 81 1208925819614630000000000 22 2097152 52 2251799813685250 82 2417851639229260000000000 23 4194304 53 4503599627370500 83 4835703278458520000000000 24 8388608 54 9007199254740990 84 9671406556917030000000000 25 16777216 55 18014398509482000 85 19342813113834100000000000 26 33554432 56 36028797018964000 86 38685626227668100000000000 27 67108864 57 72057594037927900 87 77371252455336300000000000 28 134217728 58 144115188075856000 88 154742504910673000000000000 29 268435456 59 288230376151712000 89 309485009821345000000000000 30 536870912 60 576460752303423000 90 618970019642690000000000000

Subscribe to view the full document.

Problem-Solving Strategies Individual Differences: Cross-Cultural Comparisons in Problem-Solving Strategies Güss and Wiley (2007) students in U.S., Brazil, India questionnaire on preferences in problem-solving strategies frequency of use effectiveness ease of use
Cross-Cultural Comparisons in Problem-Solving Strategies
• Spring '08
• Quintanna
• Gick, Analogy Approach

{[ snackBarMessage ]}

###### "Before using Course Hero my grade was at 78%. By the end of the semester my grade was at 90%. I could not have done it without all the class material I found."
— Christopher R., University of Rhode Island '15, Course Hero Intern

### What students are saying

• As a current student on this bumpy collegiate pathway, I stumbled upon Course Hero, where I can find study resources for nearly all my courses, get online help from tutors 24/7, and even share my old projects, papers, and lecture notes with other students.

Kiran Temple University Fox School of Business ‘17, Course Hero Intern

• I cannot even describe how much Course Hero helped me this summer. It’s truly become something I can always rely on and help me. In the end, I was not only able to survive summer classes, but I was able to thrive thanks to Course Hero.

Dana University of Pennsylvania ‘17, Course Hero Intern

• The ability to access any university’s resources through Course Hero proved invaluable in my case. I was behind on Tulane coursework and actually used UCLA’s materials to help me move forward and get everything together on time.

Jill Tulane University ‘16, Course Hero Intern