標題: 求教!請大蝦們出手指教! [打印本頁] 作者: 牧童 時間: 2007-5-5 23:26 標題: 求教!請大蝦們出手指教! 如下兩句話
請高手給翻譯成漢語!先謝謝!
Are inferences to be made about levels not included in the experiment? If yes, then perhaps this factor should be random.
Were the levels of a factor determined in a nonrandom manner? If yes, then perhaps this factor should be treated as fixed.
In the traditional "frequentist" approach, fixed and random factors need to be distinguished. In a Bayesian approach there is no such distinction and all factors are random variables associated with some sort of distribution function.
Fixed factors are factors in which the classes comprise all of the possible classes of interest that could be observed. For example, the sex of an animal is either male, female, sterilized male, or sterilized female. If the number of classes in a factor is small and confined to this number even if conceptual resampling were performed an infinite number of times, then the factor is likely fixed. Other examples are age classes, lactation number, management system, cage number, and breed class. Usually if the sampling were to be repeated a second time, those factors which maintain the same classes between the two samplings would be fixed factors. For example, a growth trial on pigs using two diets would probably need to use the same housing facilities, the same age groups of pigs, and the same diets, but the individual pigs would necessarily have to be new animals because an animal could not go through the same growth phase a second time in its life. Pig effects would be considered a random factor while the other effects would be fixed.
Random factors are factors whose levels are considered to be drawn randomly from an infinitely large population of levels. As in the previous pig experiment, pigs were considered random because the pig population of the world is large enough to be considered infinitely large, and the group that were involved in that experiment were a random sample from that population. In actual fact, however, the pigs on that experiment were likely sampled from those relatively few pigs that were available at the time the trial started, but still they are considered to be a random factor because if the experiment were to be repeated again, there would likely be a completely different group of pigs involved.
Another way to determine if a factor is fixed or random is to know how the results will be used. In a nutrition trial the results infer something about the diets in the trial. The diets are specific and no inferences should be made about other diets not tested in the experiment. Hence diet effects would be a fixed factor. In contrast, if animal effects were in the model, inferences about how any animal might respond to a specific diet may need to be made. There should not be anything peculiar about the animal on the trial that would nullify that inference. Animal effects would be a random factor.
In general, a few questions need to be answered to make the correct choice of fixed or random factor designation. Some of the questions are
1.
How many levels of the factor are in the model? If small, then perhaps this is a fixed factor. If large, then perhaps this is a random factor.
2.
Is the number of levels in the population large enough to be considered infinite? If yes, then perhaps this factor is random.
3.
Would the same levels be used again if the experiment were to be repeated a second time? If yes, then perhaps this factor is fixed.
4.
Are inferences to be made about levels not included in the experiment? If yes, then perhaps this factor should be random.
By studying the scientific literature, a researcher should be able to get some help in this decision process. If in doubt, then the assistance of an experienced statistician should be sought.
In a Bayesian context, a prior distribution needs to be assumed about each of the factors. For random factors, typically these might be assumed to have a Normal distribution with a particular mean and variance. For fixed factors, an uniform distribution may be assumed or a prior distribution in which the factors are proportional to a constant. In a Bayesian context, even the variances need to have an assumed prior distribution. The prior distributions are combined to derive the distribution of the observations, and then are used with the distribution of the data to arrive at a posterior distribution from which inferences may be made.
上面加了漢字的是想請大家?guī)椭g的
我拿不準啊
所以才拿來這里求教的
謝謝兩位了!
[ 本帖最后由 牧童 于 2007-5-7 23:54 編輯 ]作者: 牧童 時間: 2007-5-7 23:57
我只所以不把自己的翻譯拿出來,就是怕大家受錯誤的暗示
現(xiàn)在拿出來,主要是想給大家提供一些專業(yè)詞匯,免得大家去查字典了作者: 矮子 時間: 2007-5-8 00:37 Are inferences to be made about levels not included in the experiment? If yes, then perhaps this factor should be random.
Are inferences to be made about levels not included in the experiment? If yes, then perhaps this factor should be random.
試驗之外的水平是否由推論而出？如果是，那么該因子或許是隨機的 5.
Were the levels of a factor determined in a nonrandom manner? If yes, then perhaps this factor should be treated as fixed.
一個因子的水平是否由非隨機方式?jīng)Q定？如果是,那么該因子也許是固定的 作者: 矮子 時間: 2007-5-8 01:30
Are inferences to be made about levels not included in the experiment? If yes, then perhaps this factor should be random.
Are inferences to be made about levels not included in the experiment? If yes, then perhaps this factor should be random.
試驗之外的水平是否由推論而出？如果是，那么該因子或許是隨機的
Were the levels of a factor determined in a nonrandom manner? If yes, then perhaps this factor should be treated as fixed.
一個因子的水平是否由非隨機方式?jīng)Q定？如果是,那么該因子也許是固定的作者: 牧童 時間: 2007-5-9 11:33
在這兩句英文里的should該翻譯為"也許"還是該翻譯為"應該"?它跟句中的單詞"perhaps"是什么關系啊?請各位繼續(xù)指點!
4.
Are inferences to be made about levels not included in the experiment? If yes, then perhaps this factor should be random.
5.
Were the levels of a factor determined in a nonrandom manner? If yes, then perhaps this factor should be treated as fixed.作者: jy02281190 時間: 2007-5-11 12:35 標題: 對should問題愚見 我認為這里的should be是虛擬語氣，不需要翻譯出來，贊成矮子的翻譯作者: mzscym 時間: 2007-5-11 19:48
矮子譯的不錯，想不到還真有高手!不過牧童用來教學生，學生可能難以接受。作者: 牧童 時間: 2007-5-12 01:59
:'( :'( :'(作者: 在路上 時間: 2007-5-17 14:04
有點難，學習學習吧！作者: cheng_zhang 時間: 2008-2-4 14:02 標題: 我不同意這個翻譯 這種數(shù)學生統(tǒng)的筆譯很費時的： Are inferences to be made about levels not included in the experiment? If yes, then perhaps this factor should be random. 試驗之外的水平是否由推論而出？如果是，那么該因子或許是隨機的