Question 63·Hard·Command of Evidence
Self-Reported Versus Measured Smartphone Battery Health and Resulting Performance Issues
| Age group | Average self-reported battery health (% of original capacity) | Average lab-measured battery health (% of original capacity) | Incidence of unplanned shutdowns (per 100 users per month) |
|---|---|---|---|
| 18–29 | 91 | 78 | 5.4 |
| 30–49 | 88 | 82 | 3.1 |
| 50–64 | 85 | 83 | 2.7 |
| 65+ | 80 | 79 | 2.5 |
After surveying more than 4,000 smartphone owners, a consumer-electronics research group concluded that younger users tend to overestimate the health of their phone batteries, and this age group also has the highest rate of unexpected device shutdowns among the age groups surveyed.
Which choice best describes data from the table that support the researchers’ conclusion?
For “Which choice best describes data that support the conclusion?” questions, underline the conclusion’s required elements (the group, the comparison/trend, and any outcome). Then locate the single row(s) in the table that satisfy all elements at once (here: largest self-reported minus measured gap and highest shutdown incidence) and pick the option that reports those exact figures without swapping in numbers from a different row.
Hints
Track the conclusion’s two required pieces
The conclusion requires evidence for both (1) overestimation (self-reported vs. measured) and (2) the highest shutdown rate—and they must refer to the same age group.
Compute the overestimation gap
For each age group, compare self-reported battery health to lab-measured battery health by subtracting measured from self-reported.
Verify the shutdown value for that same row
After you identify the age group with the largest gap, check the shutdown incidence in that exact row and confirm it is the largest in the shutdown column.
Step-by-step Explanation
Restate what the question is asking for
The researchers’ conclusion makes two claims:
- Who? Younger users.
- What pattern? They overestimate their battery health more than others, and this age group also has the highest rate of unexpected shutdowns.
So the correct answer must describe data showing both big overestimation for younger users and the highest shutdown rate for that same group.
Find which age group overestimates battery health the most
Compare self-reported vs. measured battery health for each age group by finding the difference (self-reported minus measured):
- 18–29: percentage points
- 30–49: percentage points
- 50–64: percentage points
- 65+: percentage point
The youngest group (18–29) has by far the largest gap between what they report and what the lab measures, so they overestimate the most.
Find which age group has the highest shutdown rate
Now compare the "Incidence of unplanned shutdowns" column:
- 18–29: 5.4
- 30–49: 3.1
- 50–64: 2.7
- 65+: 2.5
Again, the 18–29 group has the highest shutdown incidence, matching the second part of the conclusion.
Match the correct data description to the answer choices
We need the choice that (1) focuses on the 18–29 group, (2) states that their self-reported battery health is much higher than the measured value (a 13-point gap), and (3) notes that they have the highest shutdown incidence (5.4 per 100 users). The choice that does all of this is:
Users aged 18–29 report 91% battery health versus 78% measured, a 13-point overestimate, and they also have the highest shutdown incidence at 5.4 per 100 users.