1.5 Exercises

i2ds: Exercises

1.5.1 Create a summary in R Markdown

Create a R Markdown document (i.e., with the extension .Rmd):

  • Add an appropriate header (with a title, your name, and the current date).
  • Structure the document (with headings) to reflect the sequence of these exercises.
  • Save your document as i2ds_ex01_YourName.Rmd (with YourName actually indicating your name).

Regularly knit your .Rmd document into an .html output document — and submit the latter as your exercise solution.

1.5.2 Create a data file

In Section 1.2.1, the term data was explained by describing a file of health records. Create such a file (e.g., by inventing some patients, their characteristics, diagnoses, etc.) and answer the following questions:

  1. What are the observations, variables, and values of your file?

  2. In which form did you arrange the observations and variables? Can you use alternative forms to record the same information?

  3. What type of variables (e.g., numbers vs. text) did you use? Can you think of alternative ways of expressing the same information?

  4. Which health-related aspects of the patients could not be recorded in this file?

  1. Which tools (e.g., software programs) did you use to create your file? Can you think of alternative tools?

1.5.3 Data vs. representations

Please answer the following questions in a few sentences (ideally in your R Markdown document from Exercise 1.5.1).

  1. How could you record and store the data of a particular news report on TV? How would you quantify the information contained in it?

  2. Describe the similarities of and differences between mental and external representations for an example (e.g., concepts, numbers, music).

  3. Why do we find it more difficult to do mental arithmetic in a foreign language? How does this differ from calculating in a different number system (e.g., using the Roman numerals)?

  4. Teresa wants to save a record of a conversation on her mobile phone. She takes screenshots of all associated messages and stores them on an online server. Describe the potential benefits and costs of this transformation in terms of data formats and future uses.

  5. Reflect upon a mobile phone as a tool. Which tasks is it designed for? Which other functions does it provide? How does its ecological rationality vary as a function of its user?

1.5.4 Representing music

Consider different ways of capturing and representing music.

  • a sinfony as a notation on sheets vs. a performance by an orchestra
  • recording on vinyl vs. in digital (e.g., .mp3) format
  • reporting experience on Likert rating scale (e.g., to rate enjoyment and emotional impact)

Which of these mark different representations of different things (melody vs. experience of music) vs. of the same thing (sound waves).

1.5.5 Conceptual summary

Summarize one of the key concepts of Section 1.2. At this point, your.Rmd document does not yet need any code chunks, but it should:

  • use headings to structure your document (of at least two levels);
  • add paragraphs of text, with some words in italics or bold fonts;
  • include one or more lists (with bullets or numbers);
  • include an image (e.g., reading in our course logo or Figure 1.4);
  • include a list of references (with links to additional resources).

Regularly knit your .Rmd document into an .html output document — and submit the latter as your exercise solution.