| 所在主题： | |
| 文件名: WEIGHTING.pdf | |
| 资料下载链接地址: https://bbs.pinggu.org/a-1697675.html | |
| 附件大小: | |
|
1. Weight matters
This paper deals with weighting, its function in statistical analysis, and its use in SPSS. A typical problem involving weighting can be seen in the following example. A survey has been carried out on the population of a certain region of the United States, to estimate voting preferences in the region for an upcoming national election. A sample of 1000 voters, including 500 African Americans (AA) and 500 Non African Americans (NAA) has been drawn at random, and the result was that 60% of the sample announced they would vote Democratic. The pollster in charge hastily made the prediction that Democrats would win by a near landslide margin. As it turned out, this was a wrong prediction: 55% of voters chose the Republican candidate, and just 45% cast the Democratic ballot. What went wrong with the pollster's prediction is that it failed to take into account the fact that blacks were over-represented in the sample, and at the same time they were very strongly Democratic (about 80%) while whites and other non-blacks were under-sampled and they were also more evenly divided between the two parties. The prediction of 60% Democratic was based, in fact, on 40% of the NAA sample and 80% of the AA intending to vote for the Democratic Party. As the same number of people from each ethnic group was interviewed, the overall simple average was 60% Democratic. But in fact, blacks were not even close to represent 50% of the population. Their share in the region was about 18% of the population. So in fact giving each portion of the sample its proper demographic weight (82% non-blacks, 18% blacks) gives a very different prediction |
|
熟悉论坛请点击新手指南
|
|
| 下载说明 | |
|
1、论坛支持迅雷和网际快车等p2p多线程软件下载，请在上面选择下载通道单击右健下载即可。 2、论坛会定期自动批量更新下载地址,所以请不要浪费时间盗链论坛资源,盗链地址会很快失效。 3、本站为非盈利性质的学术交流网站,鼓励和保护原创作品，拒绝未经版权人许可的上传行为。本站如接到版权人发出的合格侵权通知，将积极的采取必要措施；同时，本站也将在技术手段和能力范围内，履行版权保护的注意义务。 (如有侵权，欢迎举报) |
|
京ICP备16021002号-2 京B2-20170662号
京公网安备 11010802022788号
论坛法律顾问：王进律师
知识产权保护声明
免责及隐私声明
