Question

in each study, the data collected is what level of measurement? letter grade (a, b, c, d, f): nominal ratio interval ordinal temperature in celsius: nominal ratio interval ordinal number of traffic tickets: nominal ratio interval ordinal

Explanation:

1. For letter grades (A, B, C, D, F), there is an order (A is better than B, etc.), so it is ordinal.
2. Celsius temperature has equal - intervals between values but no true zero (0°C is an arbitrary point), so it is interval.
3. The number of traffic - tickets has a true zero (0 tickets means none), and ratios are meaningful (2 tickets is twice as many as 1 ticket), so it is ratio.

Answer:

1. Ordinal
2. Interval
3. Ratio