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How to force R to use a specified factor level as reference in a regression?
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See 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 ...
How to get a list of installed android applications and pick one to run
...ng with a server. Is there any guidelines?
– dowjones123
Jun 30 '15 at 20:07
1
@dowjones123 Did u...
Using “like” wildcard in prepared statement
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PreparedStatement ps = cn.prepareStatement("Select * from Users where User_FirstName LIKE ?");
ps.setString(1, name + '%');
Try this out.
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What is meaning of boolean value returned from an event-handling method in Android
... TAG = "TAG"
@SuppressLint("ClickableViewAccessibility")
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
setContentView(R.layout.activity_main)
findViewById<LinearLayout>(R.id.linearlayout_root).setOnTouchListener { v, e...
Grep characters before and after match?
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3 characters before and 4 characters after
$> echo "some123_string_and_another" | grep -o -P '.{0,3}string.{0,4}'
23_string_and
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ValueError: invalid literal for int() with base 10: ''
...answered Apr 23 '19 at 3:21
Brad123Brad123
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Sorting a list using Lambda/Linq to objects
... answered Jan 2 '13 at 16:32
gls123gls123
4,89922 gold badges2424 silver badges2626 bronze badges
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Easiest way to compare arrays in C#
...or tuples via using StructuralComparisons type:
object[] a1 = { "string", 123, true };
object[] a2 = { "string", 123, true };
Console.WriteLine (a1 == a2); // False (because arrays is reference types)
Console.WriteLine (a1.Equals (a2)); // False (because arrays is reference types)
IStruct...
Using an integer as a key in an associative array in JavaScript
...ered Mar 24 '14 at 12:51
Jesuslg123Jesuslg123
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Why should I use a pointer rather than the object itself?
... using a pointer (regardless of how it was allocated) because you want the function to which you're passing it to have access that that specific object (not a copy of it). However, in most situations, you should prefer reference types to pointers, because this is specifically what they're designed f...