= Bolt Tutorial, Part III: Analytics =

== Micro-experiments ==

Suppose you have two alternative lessons for a given concept.
They may be completely different,
or they may differ in appearance.
Which is better?
Or is each better for some identifiable subset of students?
To investigate, create a '''micro-experiment'''
in which students are randomly shown one lesson or the other,
and then perform an exercise.
{{{
function show_lesson() {
    return select(
        name('show_lesson'),
        valuator('rand'),
        lesson(
            filename('lesson1.php')
        ),
        lesson(
            filename('lesson2.php')
        ),
    }
);

return sequence(
    name('course'),
    show_lesson(),
    exercise(
        filename('exercise.php')
    )
);
}}}

This uses a new control structure, '''select()'''.
This takes a 'valuator' function (in this case, random)
and a set of units.
It shows the unit for which the valuator function has the largest value.

== Lesson comparison ==

After a number of students have passed through the micro-experiment,
you may have enough data to conclude something about your lessons.
To do this, go to the course Control Panel
and click Lesson Compare.

== Course maps ==