If you think that your data is distributed normally (stat 414 uses nomral probability plot to check that), you can enter your series into the left window (spaces, including newlines, and comma separated values are supported). This will compute the mean and variance and redirect you to the tscore calculator 
A road to injustice
Saturday, September 24, 2016
Student's t confidence interval
This calculator computes sample mean for the tscore calculator.
Rotating the distribution
There are two ways to represent a distribution. Normally, you do it like on the left diagram, with vertical bars (a histogram, pd.f.) which stands on the (Xaxis) value and whose height is proportional to the likelihood/probability. It is lends nicely itself for integrating the probabilities to get into a range of values. It is however not suitable for finding the average. To find the average, you need to rotate the plot 90 degrees so that bar height is proportional to the value and bar width is the probability to get into it, like it is on the right.
Specify the distribution in [value, likelihood] format below:
I started to think however that if we make the height of the bar proportionally to the density on the interval, that is count of occurrence per interval length, then histogram becomes suitable for average computation. What is the difference with the right diagram them? We compute the average density whereas right diagram still computes the average value?
Specify the distribution in [value, likelihood] format below:
Thursday, September 22, 2016
Why invention is different from discovery? [duplicate]
This question already has an answer here:
You say that discovery discovers something preexisting (in the world) whereas inventor comes up with a new idea. But, don't you discover the ideas?
As I understand, there is an abstract world of ideas, where all abstract notions, i.e. ideas, live in. You just discover one or another. They usually tell you how to get from A to B in an optimal way. One way is bad, another is good. And what you do when solve a problem, you find those ways. Mathematicians know very well that solutions are not arbitrary. They exist before you discover them (nobody needs arbitrary solutions as nobody needs garbage). Is desired solution a discovery or an invention? Why do people, particularly academists, insist that there is a distinction between invention and discovery, once you realize that inventors just discover the ideas from the ideal world of ideas/solutions?
 
marked as duplicate by Camil Staps♦, Dave, John Am, commando♦, Eliran H Aug 4 at 14:16
This question was marked as an exact duplicate of an existing question. If this question is different, please edit itto explain how it is different or ask a new question.
deleted by Community♦ Sep 10 at 0:51 (RemoveDeadQuestions)
This question was automatically deleted. Please see the help center for more information.
 

Giving advises in individualist society [closed]
I see that our society has transformed into individualist society and every individuals around me are quite individualistic. People are quite efficient at the work but their spendings at the private time, when I see them, is crazy. Yet, when I try to fix it with my deepest affections, they prefer to wound me to display that they need the money from me, not the advises. They are ready to listen only from the rich people.
Should I start explaining them anything by my initiative when I feel that I need to? This answer raises also in case when the initiative is theirs, when they ask me anything to explain. I need to decide how deeply should I go in the answer. I can give a short answer, which hardly explains anything or go into the details that I feel critical and important. But, they are not even informed about such nuances ever exist and, therefore, do not ask about them. Should I start telling them something on my own initiative?
Suppose now that one of them goes blindly to fall out of the window. Should I stop them, telling what they are essentially doing? I ask because I see a contradiction here. I should stop them from the ethics point of view, but, I should not from the individualist point of view. From individualist point of view I should silently let them to fall. This is their wish after all for me to keep my mouth shut to let them do quietly what they want to.
Another contraction arises if their action harms me. For instance, you know that you must buy a household and a car(s). It is a must individualist lifestyle. Yet, it destroys the environment. The individualist lifestyle of the dream not only pumps out their budget, it also drains the oil reserves and destroys the planet that I live on. So, on one hand, I must defend my interest and tell them what they are doing. On the other hand, I should shut up and enjoy whatever they do. How to resolve this contradiction?
 
closed as unclear what you're asking by virmaior Jul 31 at 23:18
Please clarify your specific problem or add additional details to highlight exactly what you need. As it's currently written, it’s hard to tell exactly what you're asking. See the How to Ask page for help clarifying this question.If this question can be reworded to fit the rules in the help center, please edit your question.
deleted by Community♦ Aug 10 at 3:00 (RemovedAbandonedClosed)
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Await.result is faster than pure Futures
I tried
def fibAwait(grainSize: Int) = {
def seqF(n: Int): Int =
if (n < 2) n else seqF(n1)+seqF(n2)
def parF(n: Int): Int = if (n < grainSize) seqF(n) else {
val flist = Future.sequence(List(1,2) map
(i => Future{parF(ni)})
Await.result(flist, Duration.Inf) sum ;
}
parF(45)
}
vs
def fibFuture(grainSize: Int) = {
def seqF(n: Int): Int =
if (n < 2) n else seqF(n1)+seqF(n2)
def parF(n: Int): Future[Int] =
if (n < grainSize) future{seqF(n)}
else {
val flist = List(1,2).map(i => parF(ni))
Future.sequence(flist) map (_.sum)
}
Await.result(parF(45), Duration.Inf)
}
Both compute fib(45) where bottom 42 levels are computed sequentially and upper levels 45 downto 43 start a parallel computation. Benchmarking gives time in centiseconds (1/100 of a second). Both end up in around 67 seconds but first seems to show lower time (needs to be proved with statisitcal test):
(1 to 10) foreach (_ => println(List(fibAwait _ , fibFuture _). map (f => timeit(f(42))._2)))
List(664cs, 696cs)
List(634cs, 707cs)
List(725cs, 738cs)
List(653cs, 702cs)
List(644cs, 680cs)
List(557cs, 684cs)
List(667cs, 683cs)
List(638cs, 765cs)
List(751cs, 700cs)
List(654cs, 688cs)
def fibAwait(grainSize: Int) = {
def seqF(n: Int): Int =
if (n < 2) n else seqF(n1)+seqF(n2)
def parF(n: Int): Int = if (n < grainSize) seqF(n) else {
val flist = Future.sequence(List(1,2) map
(i => Future{parF(ni)})
Await.result(flist, Duration.Inf) sum ;
}
parF(45)
}
vs
def fibFuture(grainSize: Int) = {
def seqF(n: Int): Int =
if (n < 2) n else seqF(n1)+seqF(n2)
def parF(n: Int): Future[Int] =
if (n < grainSize) future{seqF(n)}
else {
val flist = List(1,2).map(i => parF(ni))
Future.sequence(flist) map (_.sum)
}
Await.result(parF(45), Duration.Inf)
}
Both compute fib(45) where bottom 42 levels are computed sequentially and upper levels 45 downto 43 start a parallel computation. Benchmarking gives time in centiseconds (1/100 of a second). Both end up in around 67 seconds but first seems to show lower time (needs to be proved with statisitcal test):
(1 to 10) foreach (_ => println(List(fibAwait _ , fibFuture _). map (f => timeit(f(42))._2)))
List(664cs, 696cs)
List(634cs, 707cs)
List(725cs, 738cs)
List(653cs, 702cs)
List(644cs, 680cs)
List(557cs, 684cs)
List(667cs, 683cs)
List(638cs, 765cs)
List(751cs, 700cs)
List(654cs, 688cs)
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