Question

researchers used anonymized location data from the us and côte divoire to document peoples daily patterns of mobility, using these results to test the efficacy of the researchers predictive computer model. in each country, unidirectional cycles among two, three, or four locations were empirically the most common pattern types; the graph shows each of these pattern types as a proportion of all instances found for that country (e.g., the measured value for cl 3 in the graph, 0.12, indicates that the three - location pattern constituted 12% of all pattern instances in the côte divoire data).
which choice most effectively uses data from the graph to illustrate the researchers conclusion?
a) under the assumption that density is more salient than preferences, the us 2 and cl 2 proportions are approximately 0.65 and 0.85, respectively, significantly higher than the values predicted under the other assumption and thus farther than those predictions from the measured values.
b) under the assumption that preferences are more salient than density, the two - location patterns (us 2 and cl 2) were predicted to be most frequent in the data even though neither proportion was projected to exceed 0.5, well below the proportion predicted under the other assumption.
c) under the assumption that preferences are more salient than density, the us 2 and cl 2 proportions were predicted to be in the range of 0.3 to 0.5, placing them farther from the measured values than were those predicted under the other assumption.
d) under the assumption that preferences are more salient than density, the us 2 and cl 2 proportions were predicted to be approximately 0.45 and 0.35, respectively, both below the measured values, whereas under the other assumption, the model overestimated the proportion for us 2 and overestimated that for cl 2.

Explanation:

• Analyze each option:
• Option A: Mentions "density is more salient than preferences" which is not relevant to the researchers' conclusion about testing the model with measured vs predicted values under the "preferences are more salient than density" assumption (as per the problem context).
• Option B: The measured values (from the graph) for US 2 (two - location pattern in the US) and CI 2 (two - location pattern in Côte d'Ivoire) are well above 0.5 (the measured US 2 proportion is around 0.7 and CI 2 is around 0.8). If under the "preferences are more salient" assumption, the predicted values are well below the measured values (as the model is being tested), this option aligns with using the graph data to illustrate the researchers' conclusion.
• Option C: The measured values for US 2 and CI 2 are much higher than the range 0.3 - 0.5. But the key is that the measured values are above 0.5 and the predicted (under the "preferences" assumption) are below, not just the range.
• Option D: The description of over - estimation and under - estimation is incorrect as per the graph data (measured values are higher than predicted under the "preferences" assumption).

Answer:

B. Under the assumption that preferences are more salient than density, the two - location patterns (US 2 and CI 2) were predicted to be most frequent in the data even though neither proportion was projected to exceed 0.5, well below the proportion predicted under the other assumption.