Self-study
Journalist: Support Newspapers generally report on only those scientific studies whose findings sound dramatic. ████████████ █████████ ███████ █████ █████ █████████████ ████████ █████ ███ ████████ ███████████ ███ ████ ████████ ████ █████████ ███████ █████ █████ ██████████ ███████ █████ ████████ ████████ ██████████ █████████ ██████████ █ █████ █████████████ █████ ████ ██ ████ ██████ ██ ████ ████████ ████████ ████ █ █████ ██████████ ██████
The Journalist's Reasoning
The journalist observes that newspapers generally report only on studies with dramatic-sounding findings. She also observes that there are more newspaper stories about small observational studies than about large randomized trials. From these two observations, the journalist concludes that a small observational study must be more likely to have dramatic findings than a large randomized trial.
In other words, the journalist's reasoning is: newspapers favor dramatic findings, and small studies get more newspaper coverage, so the rate at which small studies produce dramatic findings must be higher than the rate for large trials.
Identifying the Flaw: Rate v. Amount
The journalist's conclusion is about rates. She's claiming that any given small observational study is more likely to produce dramatic findings than any given large randomized trial. But the evidence she cites is about raw numbers of newspaper stories. More stories about small studies doesn't necessarily mean that a higher percentage of small studies have dramatic findings.
To see why, imagine there are 1,000 small observational studies conducted and only 20 large randomized trials. Suppose 10% of each type produce dramatic findings. That gives us 100 small studies with dramatic findings but only 2 large trials with dramatic findings. Newspapers would then write far more stories about small studies, not because small studies are more likely to have dramatic findings, but simply because there are way more small studies out there. So you can view the journalist as committing a percent (or rate) v. amount flaw. To reach a conclusion about comparative rates of having dramatic findings, we'd need to know something about the total numbers of small studies and large trials.
Another framing of the flaw is that the journalist overlooks an alternate explanation for the phenomenon she observes (a greater number of stories about small studies than large trials). She jumps to the explanation that small studies must have a higher rate of dramatic findings. But the real explanation could just be that there are far more small observational studies than large randomized trials.
20.
Which one of the following ████ ██████████ █████████ █ ████ ██ ███ ████████████ ██████████
a
It casts doubt ██ ███ ███████████ ██ █ █████ ██ ███████████ ███ ███████ ██ █████ █████████ ███
The journalist never questions anyone's motives. Although the journalist mentions that newspapers tend to report only on dramatic findings, this is presented as a factual observation about what newspapers do, not as a challenge to anyone's motives or reliability.
b
It fails to ████████ ████ ████ ██ █ ███████ ████████ █████ █████████ ███ ██████████ ████████ ███ █████ ████████ ███ ██ ███████
The journalist isn't concerned with whether the scientific evidence behind dramatic findings is strong or weak. Her conclusion is about which type of study is more likely to have dramatic findings, not about the quality of the evidence those findings rest on. So whether dramatic findings can also have strong evidence behind them doesn't affect her reasoning.
c
It confuses a █████ █████ ██████████ ███████ █████ ████████ █████ ████████ ████ █ ███████ █████ █████ █████ █████████████ ████████
The journalist doesn't mix up any claims. She treats the first premise (newspapers report only on dramatic findings) and the second premise (stories about small studies are more frequent) as separate observations that she then combines to reach her conclusion. She may draw the wrong conclusion from those observations, but that doesn't mean she confuses one claim with the other.
d
It overlooks the ███████████ ████ █████ █████████████ ███████ ███ ███ ████ ██████ ████ █████ ██████████ ███████
This identifies the flaw. The journalist concludes that small observational studies have a higher rate of dramatic findings, based on the fact that there are more newspaper stories about them. But if small observational studies are far more common than large randomized trials, then we'd expect more newspaper stories about them even if both types produce dramatic findings at the same rate. For example, if there are 1,000 small studies but only 20 large trials, and both types have dramatic findings 10% of the time, newspapers would still write about small studies far more often. The journalist jumps to a conclusion about rates without considering a difference in the total number of studies conducted.
e
It fails to ████ ███ ███ ███████████ ████ █ ███████ ██████ ████████ ████ █████ ████████ ██ ██ ██████ ██████ ████ █ █████ ██ ███ ███████ █████ ████████ ███
This suggests that maybe being reported on causes a study's findings to sound dramatic, rather than dramatic findings causing the study to be reported on. But the first premise tells us that newspapers generally choose to report only on studies whose findings sound dramatic. In other words, the dramatic findings come first, and the newspapers then pick which ones to report on. So the possibility (E) raises is ruled out. Reporting on a study wouldn't happen in the first place if the study didn't already have dramatic findings.