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How to force R to use a specified factor level as reference in a regression?
... the relevel() function. Here is an example:
set.seed(123)
x <- rnorm(100)
DF <- data.frame(x = x,
y = 4 + (1.5*x) + rnorm(100, sd = 2),
b = gl(5, 20))
head(DF)
str(DF)
m1 <- lm(y ~ x + b, data = DF)
summary(m1)
Now alter the factor b in DF by use of th...
What is the purpose of Verifiable() in Moq?
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answered Nov 13 '09 at 10:49
Ruben BartelinkRuben Bartelink
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How do you list the active minor modes in emacs?
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answered Oct 2 '09 at 21:02
PhilPhil
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Using current time in UTC as default value in PostgreSQL
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303
A function is not even needed. Just put parentheses around the default expression:
create temp...
Best practice for nested fragments in Android 4.0, 4.1 (
I'm writing an app for 4.0 and 4.1 tablets, for which I do not want to use the support libraries (if not needed) but the 4.x api only therefore.
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How to update a git clone --mirror?
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ralphtheninjaralphtheninja
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MySQL Results as comma separated list
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250
You can use GROUP_CONCAT to perform that, e.g. something like
SELECT p.id, p.name, GROUP_CONCAT...
How to: Define theme (style) item for custom widget
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208
Yes, there's one way:
Suppose you have a declaration of attributes for your widget (in attrs.x...
generate model using user:references vs user_id:integer
...un the migration. In rails console, you can see that this is the case:
:001 > Micropost
=> Micropost(id: integer, user_id: integer, created_at: datetime, updated_at: datetime)
The second command adds a belongs_to :user relationship in your Micropost model whereas the first does not. When...
How to kill zombie process
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edited Mar 11 at 13:00
answered Jun 5 '13 at 16:17
Wi...