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How to force R to use a specified factor level as reference in a regression?
...e 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 t...
Generate random numbers with a given (numerical) distribution
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answered Nov 24 '10 at 12:15
Sven MarnachSven Marnach
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Calculate a Running Total in SQL Server
...pdate, if you are running SQL Server 2012 see: https://stackoverflow.com/a/10309947
The problem is that the SQL Server implementation of the Over clause is somewhat limited.
Oracle (and ANSI-SQL) allow you to do things like:
SELECT somedate, somevalue,
SUM(somevalue) OVER(ORDER BY somedate
...
Django filter queryset __in for *every* item in list
...NDed Q objects would not work:
In [9]: from django.db.models import Q
In [10]: Photo.objects.filter(Q(tags__name='holiday') & Q(tags__name='summer'))
Out[10]: []
In [11]: from operator import and_
In [12]: Photo.objects.filter(reduce(and_, [Q(tags__name='holiday'), Q(tags__name='summer')]))
Out...
Python debugging tips [closed]
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share
edited Feb 4 '10 at 14:57
community wiki
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How to see top processes sorted by actual memory usage?
...ldsarnold
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Using group by on multiple columns
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answered Mar 10 '10 at 23:24
SmasherySmashery
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Performance of FOR vs FOREACH in PHP
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110
My personal opinion is to use what makes sense in the context. Personally I almost never use f...
How to prevent moment.js from loading locales with webpack?
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Tobias K.Tobias K.
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Best way to find if an item is in a JavaScript array? [duplicate]
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edited Mar 10 '19 at 21:14
awendt
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a...