托福考试

【分析解答题】

SamplingError
Often, students or employees will be asked to draw a conclusion from a huge amount of datA、That’s when a sample is introduceD、When a sample is accurate, it can represent the whole group.But when it is wrong, sampling error would occur. In statistics, sampling error or estimation error is caused by observing a single sample instead of the whole population. Sampling error can be found by subtracting the value of a parameter from the value of a statistiC、Generally, there are two methods of reducing sampling error: increasing the sample size, and ensuring that the sample can adequately represent the entire population.
Question: The professor uses one experiment to illustrate the definition of "sampling error".Explain how this example is related to the reading passage.
网考网解析：
试题答案： 答案解析：The passage talks about a statistics term "sampling error", which is caused by observing a single sample instead of the whole population. If the sample is inaccurate, sampling error might appear. The lecture cited one experiment to illustrate the term. A researcher intended to conduct an experiment to calculate the amount of fish of different sizes in one pond. The researcher scooped out one net of fish to be his statistic sample. To his surprise, there were only big fish and middle-sized fish in his net. Finally, he figured out that small fish had already escaped from his big-mesh fishing net. [听力原文] M: Well, so you may have ideas of sampling error now. As what we just learned, the accuracy of the sample has an influence on the analysis of the whole group. If the sample is inaccurate, sampling error might appear. A researcher conducted an experiment to calculate the amount of fish of different sizes -- big fish, middle-sized fish and small fish. Because it was impossible to calculate every fish in the pond, the researcher just scooped out the fish with a fishing net and obtained one net of fish as his statistic samples. It turned out that there were only big fish and middle-sized fish in his net, which made him wonder why there weren’t any small fish in the pond. After observing that some small fish did exist in the pond, he started to search why he could not obtain one sample of small fish. Finally, he figured out that this was because small fish had escaped from his big-mesh net. You see, ineffective research tools can cause sampling errors during our statistics studies. document.getElementById("warp").style.display="none"; document.getElementById("content").style.display="block"; 查看试题解析出处>>