1. Mission to Mars – A Study on Naming and Referring Michael Weigend University of Münster, Germany

2. Outline 1.Introduction: Naming and referring 2.Design of the Study “Mission to Mars” 3.Mission 1 4.Mission 2 5.Mission 3 6.Conclusion Michael Weigend, WWU Münster: Mission to Mars 2

3. Introduction Michael Weigend, WWU Münster: Mission to Mars 3

4. Names Functions: Identifying (making it distinguishable) Addressing (making it accessible) Michael Weigend, WWU Münster: Mission to Mars 4

5. Types of Names explicit - implicit direct - indirect Mom E player_1 My brother’s daughter’s dog flight.passengers[0] sqrt(2) Michael Weigend, WWU Münster: Mission to Mars 5

6. Naming and Referring to name = to create a name to refer = to use a name person = flight.passengers[i] … print(person) Michael Weigend, WWU Münster: Mission to Mars 6 Constructing an indirect name implies referring. Creating a name includes anticipating its usage.

7. Working Memory Baddeley (1974, …, 2006) Michael Weigend, WWU Münster: Mission to Mars 7

8. Naming and Reduction of Working Memory Load Michael Weigend, WWU Münster: Mission to Mars 8 flight.passengers[i].name[0] person = flight.passengers[i] first_letter = person.name[0] print(first_letter) if first_letter in "ABCDE":... Split

9. Mathematical Modeling in Science Michael Weigend, WWU Münster: Mission to Mars 9 “Let c 0 be the concentration of the hydrochloric acid in the beaker…”. E = mc² Naming conventions Short direct names instead of long indirect names

10. Design of the Study “Mission to Mars” Michael Weigend, WWU Münster: Mission to Mars 10

11. Question To what extent are students without former informatics education able to use naming techniques, when they have to write algorithms? Michael Weigend, WWU Münster: Mission to Mars 11

12. Workshops Briefing Phase 1: Interpret given instructions Phase 2: Write instructions Phase 3: Exchange instructions Phase 4: Compare the results Debriefing Michael Weigend, WWU Münster: Mission to Mars 12

13. Mission 1 Naming and Referring Michael Weigend, WWU Münster: Mission to Mars 13

14. Phase 1 – the Model Michael Weigend, WWU Münster: Mission to Mars 14 (1) Draw a five point star. One of the tips points upwards. Write the letter A in the middle of the star. (2) Draw a four point star with four beams a little bit below star A. One tip of the new star points upwards. Write the letter B at the star. (3) Mark star A. Mark star B. direct name Name of an activity

15. Phase 1 – the Model Michael Weigend, WWU Münster: Mission to Mars 15 (4) Draw circles around the tips number 1, 2 and 5 of star A. (6) Put your finger on the circle, which is at tip number 5 of A. Draw a second circle left to this circle. (9) Write the word Sauerstoff (oxygen) next to the right hand side of the circle, which is at tip number 2 of A. indirect name implicit name 62% no mistake 23 % one mistake.

16. Phase 2 – Writing Instructions Michael Weigend, WWU Münster: Mission to Mars 16 8 different problems of equal complexity At a table each student has a different problem

17. Some Results Michael Weigend, WWU Münster: Mission to Mars 17 105 students, grade 9, average age 15.3 years, 57 male, 47 female (one person did not tell ) Naming Conceptpercentage Explicit direct names (like A, B)32% Indexing66% Implicit name (like “put your finger at …”)9% Define a separate procedure (like “ to mark a polygon”) 17%

18. Discussion Michael Weigend, WWU Münster: Mission to Mars 18 Most students tend to avoid to create direct names, especially for activities. Indexing (numbering) things is easier than creating explicit direct names.

19. Mission 2 Naming Activities Michael Weigend, WWU Münster: Mission to Mars 19

20. Phase 1 – The Model Michael Weigend, WWU Münster: Mission to Mars 20 To draw a Mars habitat (1) Draw a living unit in the middle of your paper. Call it W1. (2) Draw a second living unit below W1. This new living unit is called W2. (3) … To draw a living unit … To draw a laboratory … To draw a tank (1) Draw a circle. Procedure call Procedure definition

21. Phase 1 – Solution Michael Weigend, WWU Münster: Mission to Mars 21 75% no mistake 12 % one mistake

22. Phase 2 – Writing Instructions Michael Weigend, WWU Münster: Mission to Mars 22 8 different problems of equal complexity Three instances of an aggregrat (highlighted)

23. Some Results Michael Weigend, WWU Münster: Mission to Mars 23 52 students, grade 10, average age 16.1 years, 32 male, 19 female (one did not tell). Conceptpercentage Defining procedures4% Subheadings (like “First part of the habitat”)29% Numbering the instructions (1), (2), …73%

24. Discussion Michael Weigend, WWU Münster: Mission to Mars 24 Students avoid structured programming (using procedures). Why? Avoid a split attention situation (Sweller). Extra effort to create a (and rehearse) new holistic concept of activity. Easier to use an existing concept of activity (like numbering corners).

25. Mission 3 Referring to Entities within a Complex Geometry Michael Weigend, WWU Münster: Mission to Mars 25 49 students, grade 9

26. Phase 1 – the Model Michael Weigend, WWU Münster: Mission to Mars 26 (1) The pyramid in the right corner of the platform is called corner pyramid. Write number 1 on the corner pyramid. (100% correct) Explicit direct name

27. Phase 1 – the Model Michael Weigend, WWU Münster: Mission to Mars 27 (5) When you move from the corner pyramid along the edge of the platform to the left, you reach a cube. Write 6 on this cube. (92% correct) Path-oriented reference

28. Phase 1 – the Model Michael Weigend, WWU Münster: Mission to Mars 28 (5) A Cylsphe is a cylinder with a sphere on top. Write a 5 on the cube, which is on top of the Cylsphe, which is in front of a pyramid. (92% correct) Name for a type of aggregates

29. Phase 1 – the Model Michael Weigend, WWU Münster: Mission to Mars 29 (8) Put your finger on the big sphere in the middle of the platform. At this sphere there is an arrow pointing to a pyramid. Write an 8 on this pyramid. (100% correct) Implicit direct name

30. Phase 2 – Writing Instructions Michael Weigend, WWU Münster: Mission to Mars 30 Different structure. Parts with numbers must be replaced. Write instructions! Different sets of 6 parts.

31. Some Results - Naming Michael Weigend, WWU Münster: Mission to Mars 31 ConceptPercentage Some kind of naming (including implicit)47% Introducing and using explicit entity name (like corner pyramid or X) 6% Number of an entity (“Put your finger on part 3 …”)10% Using corner pyramid (phase 1) without introducing it24% Implicit naming (“Put your finger at …”)27% Introducing and using new aggregate types (“Würzel”/”Cuder” for cube/zylinder) 6%

32. Some Results - Referring Michael Weigend, WWU Münster: Mission to Mars 32 ConceptPercentage Attribute oriented references “The cube is glued at a cylinder, which is on top of a bigger grey cube, which stands upon four white cylinders. Additionally there are two white pyramids on top of the big cube.” 55% Path-oriented references “The arrow points to a small cube. This is in front of a bigger cube. On the bigger cube there is a sphere. Write number 5 on this sphere.” 90% Aggregate-oriented references “You see a row of cubes. On top of each cube there is a sphere. Beside one cube with a sphere on top there is another sphere. Write number 6 on the sphere, which is on top of this cube. 57%

33. Some Results - Referring Michael Weigend, WWU Münster: Mission to Mars 33 ConceptPercentage Attribute oriented references “The cube is glued at a cylinder, which is on top of a bigger grey cube, which stands upon four white cylinders. Additionally there are two white pyramids on top of the big cube.” 55% Path-oriented references “The arrow points to a small cube. This is in front of a bigger cube. On the bigger cube there is a sphere. Write number 5 on this sphere.” 90% Aggregate-oriented references “You see a row of cubes. On top of each cube there is a sphere. Beside one cube with a sphere on top there is another sphere. Write number 6 on the sphere, which is on top of this cube. 57%

34. Conclusion Michael Weigend, WWU Münster: Mission to Mars 34

35. Conclusion Michael Weigend, WWU Münster: Mission to Mars 35 Thank you for your attention! Students (grades 9 and 10, without specific training) avoid creating explicit and direct names. Naming and referring are essential facets of modeling, algorithm development and communication. For this competence we need informatics education!

36. Reste (please ignore the following) Michael Weigend, WWU Münster: Mission to Mars 36

37. Algorithm Comprehension Michael Weigend, WWU Münster: Mission to Mars 37 Weigend 2009 149 children, 3rd and 4 th grade (age 9-10), “Draw thing number Ups + 1 in the middle of Main Road.” 53% correct 7 questions

38. Phonological Loop – Word Length Effect Number of stored items = Number of Items that can be articulated in 2 secs Baddeley 2003: Recall of a five-words-sequence: One syllable each: 90% Five syllables each: 50% Ellis & Hennelley 1980: Digit span of Welsh speaking children is lower. Welsh digits (385ms) take longer to articulate than their English equivalents (321ms) Michael Weigend, WWU Münster: Mission to Mars 38

39. Phase 1 – the Model Michael Weigend, WWU Münster: Mission to Mars 39 (3) A Threesphe consists of three spheres, which are connected vertically. One of the Threesphes has got a dark sphere in the middle. Write number 3 on the cube, which is beside this Threesphe on the platform. (96% correct) Names for types of aggregates Aggregate-oriented reference

40. Naming and Typing A name may be connected to a type  inducing semantics Java int add(int a, int b) { int r; r = a + b; return r; } Everyday life Mister Jones A streetcar named Desire Michael Weigend, WWU Münster: Mission to Mars 40