matlab dummyvar is creating extra binary variable

MB
2019 3 15
1 个回答
回答已采纳
更新时间：2019 3 16
5 次查看（30 天）

0 个投票

Let's say I have a categorical variable with level {'1', '2', '3'}. Now in ideal case, there should be 2 binary variable - b0 and b1 and above categorical variable should be mapped as b0=0,b1=0 for '1', b0=1,b1=0 for '2' and b0=0,b1=1 for '3'.
However, Matlab dummyvar is creating b0,b1,b2 binary variables. How can I get only 2 binary variables and above representation?
cat ={'1','2','3'}'
cat1 = categorical(cat)
result = dummyvar(cat1)
result =
1 0 0
0 1 0
0 0 1

请先登录，再回答此问题。

 采纳的回答

Jeff Miller
Jeff Miller 2019-3-16

0 个投票

I guess there is a typo in your question and you really want ''b0=1,b1=0 for '2'".
Notice that you get what (I think) you want if you just drop the first column created by dummyvar.
This explanation of dummy indicator variables may be helpful: look here

1 个评论
显示 -1更早的评论 隐藏 -1更早的评论

MB
MB 2019-3-16
Yes- thank you. I have corrected the typo and it seems to be matching with my requirement after dropping the first column.
I was just expecting 'dummyvar' to be equivalent to 'asfactor' in R but apparently it's not.

请先登录，再进行评论。

更多回答（0 个）

类别

在 帮助中心 和 File Exchange 中查找有关 Analysis of Variance and Covariance 的更多信息

标签

Community Treasure Hunt

Find the treasures in MATLAB Central and discover how the community can help you!

Start Hunting!

Translated by