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Y=, Tables, and Lists

Try prototype

  

Design Overview

  • Table of values and Stat lists separate.
  • All graphs and plots are organized in the Y= screen.

Motivation

  • 14 teachers cover scatterplots and linear regression.
  • 0 of 14 students could use the TI-73 to make a scatterplot without assistance.
  • At least 12 button presses to create a scatterplot using TI-73.
  • 5 teachers mentioned kids have problems with long command sequences.
  • 6 teachers expressed confusion about the stat menus organization.
  • 6 teachers found statistics menu organization confusing.
  • 8 teachers cover basic statistical graphs (pie chart, bar chart, box and whisker).
  • 13 teachers use calculators for statistics.

Past Iterations and User Tests

Evolution of Prototypes

 

Design Background

We wanted to address the confusing parts of the the current TI table and stats interface, as well as the complicated procedures necessary to create plots. We had learned from our teacher interviews that the table of numbers generated from graphing an equation, and the table used to enter statistics data were often confused. This is not surprising, considering that they are visually very similar. Also, some of the TI calculators have ambiguously named menu items for retrieving the name of a list, versus editing the list. To edit a list on a TI-73, one presses the "List" button. However, under the menu for "Stat", there is a list of the different list names.

Our primary strategy for coming up with new designs was to simplify. Our first design allowed users to enter in scatterplot data directly into the table used for viewing generated numbers from graphed equations. This completely eliminated any other setup necessary for creating a scatterplot, it also introduced a new set of problems.

Look at evolution of prototypes to see how this evolved into our final design.

Design Walkthrough

1.

Create functions and plots from the Y= screen.
2.

Users can input data for a scatterplot from within the Y= screen. The association between the graph and the Lists have been removed.
3.

Table view includes plot tables and the table of values for equations, separated from the statistical lists.
4.

To adjust a linear equation dynamically, the user may use the left/right keys to move between the slope and the y-intercept fields, and they can use the up/down keys to increase or decrease the parameter in focus. Fractions, though not prototyped in this interface due to time constraints, would be a part of the design for future work.
5.

To view the corresponding table of values, the user can press on the “Table” button.