Projects: TEEMSS2 : notes on representing large and small numbers on the data collector graph
This page last changed on Aug 20, 2008 by ehazzard.
Currently the data collector graph switches to scientific notation for large and small number, e.g., 12000 is displayed as 12E3, and .0036 is displayed as 3.6E-3. This is hard for kids to grasp. It arises mainly with light (large numbers possible) and millivolts (small numbers possible), but also with time if one gets careless with the scrolling or does long-term experiments.
There are several other options. Perhaps an author should be able to choose one, but the best option should be chosen as the default.
1. leave as is. Explain scientific notation in every activity where it may arise. OK for HS, sort of OK for MS, problematic for elementary.
2. Change the label by adding E3 or E-3, or alternatively X 10exp3 or X 10exp-3, or alternatively with the superscript exponent. So when a high light level is measured, the Y-axis label will change from Light (lux) to Light (lux) x E3 automatically, and the numbers on the graph will switch accordingly. This could be confusing if the student doesn't notice the change in label, but it's less confusing than 3.5E3.
3. automatically change the text of the units, e.g. from Light (Lux) to Light (kilolux) or Light (megalux); from Voltage (Volts) to Voltage (milliVolts) and so forth. The range of the graph stays within .010-900 before switching (that's how it currently works).
3a. It would be ideal if the x-axis switched automatically from sec to min to hr. I don't think days are needed.
4. A more modest improvement: change the point at which it switched to E3 from full scale = 999 to full scale = 9999. This would help in common situations measuring light.
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