Wednesday 30 November 2011
Math 215 Class Record
Goal

Understand Test Score Data, with a focus on Standard Error
1. Discuss RIT, CRT, Scale Scores.
2. Have them analyze the data from Grade 5.pdf.
a. If a child got a 212 RIT and got 211 the next time, is it reasonable to
view the child as having decreased his/her knowledge? Why or why
not?
b. If a child got a 212 RIT and got 206 the next time, is it reasonable to be
concerned about the child? Roughly how likely is this to happen? If
you have 30 kids, what is the expected number of kids who would get
outside their test range?
c. NWEA predicted that a MAP score of 219 would correspond to the
borderline between proficient and below proficient. Does your class
data make this seem like a reasonable estimate?
d. Have them plot their grade 5 data on a histogram. Does it look like a
bell curve? What if they plotted a school’s data? A district’s data? All
state data?
3. Use Table 1 and Table 7 to estimate how MAP predicts SBA. Focus on fifth
grade. Here are some questions for them to address.
a. Table 1 estimates the minimum score for proficiency to be 219. Table
7 estimates a child getting this score has about a 50% chance of
scoring proficient. Does this make sense?
b. If a child gets an RIT of 275, are they guaranteed to score proficient on
the SBA?
c. If a child gets an RIT of 170, do they have no chance to score proficient
on the SBA?
d. If a child scores between 215-220, they have about a 50/50 chance of
scoring proficient. What might you say to a parent who complains
about taking the test, saying that they could flip a coin and have just as
good of a predictor of their child scoring proficient.
4. Give them the course evaluation.