作者allen1985 (我要低调 拯救形象)
站内Statistics
标题Re: [讨论] 关於ancova与T-test的结果
时间Sat Sep 10 21:20:37 2011
※ 引述《gioia000 (我没有要引战啊)》之铭言：
: 想请教版上高手..问到自删
: 实验数据共两次测验分为L1与L2
: 实验组跟对照组 两次测验之间的ANCOVA都未达显着
: 实验组的成对T-test有显着差异 对照组则无
: 所以实验组组内前後测达显着差异 可是组间却没有显着
: 这实验结果是失败了吗?还是应该如何解释比较合理?或者有更好的跑法?
: 感谢回复
: ----
: 回应一楼:
: L1 L2是两次测验的成绩 因为不同班 所以拿段考成绩当作共变数分别跑两次ANCOVA
: 两次测验都没有显着差异 前测平均72.9 VS 78.4 後测79 VS 81
: 段考平均则是夸张的561 VS 634 我以为後测变成2分的差距会有显着差异
: 然後我用相依样本T-test(同一母群) 测出实验组有显着差异 (平均明显进步较多)
: 不知道这样的解释清楚了吗?谢谢...不好意思阿记脑袋不太灵光XD
Frankly speaking, I still cannot understand your question clearly.
First, what is your response (y) ? average grade?
Second, what is your independent variables?
And what is your conti. independent variable and your discrete independent
variable?
Can you write down your linear models?
For example,
ANCOVA
post = beta_0 + beta_1X_1 + beta_2X_2 + error,
where X_1 means different class and X_2 means pre grades.
Besides, the testing result of beta_2 is not significant under alpha%
significant level.
Paired T test
Post - Pre = mu + error
where mu means the average difference between post and pre.
So, the testing result for mu is significant that mu is not equal to 0.
I don't know whether I understand your questions already.
--
※ 发信站: 批踢踢实业坊(ptt.cc)
◆ From: 75.180.59.249
※ 编辑: allen1985 来自: 75.180.59.249 (09/10 21:21)
※ 编辑: allen1985 来自: 75.180.59.249 (09/10 21:23)