Why are null and alternative hypothesis mutually exclusive?
335961
They have to be by definition.  One is the assumed hypothesis (null) and the other is an alternate (what is true if the null hypothesis isn't).  By the very definition of the terms, they can't both be true.  So H0: X= N goes with the alternatve H1: X IS NOT EQUAL to N.
923495
You can use a z-test for a population proportion.  The test statistic is\n\n(phat-p)/sqrt(p(1-p)/n).\n\nHere phat = 34/66, p = 0.5 under the null hypothesis that the coin is fair, and n = 66.  Compare this test statistic to a standard normal to determine if you would reject the null or not.  I would not suspect hat you would reject though.\n\nIt is appropriate to use this test when the number of successes and the number of failures are greater than or equal to 5, which is the case here.
712323
p is a probability. So you're almost right - the question is, can you have a p value of 0 or 1?\nAnd the answer is yes. Although nearly every single statistical test you will use will never give 0 or 1, it is theoretically possible.
180525
Hypothesis testing means assesing, with a degree of confidence, whether an hypothesis (an assumption) is correct or not. Applications for these techniques just fluorish once you have a grasp on it. For example, you can test whether your clients are satisfied or not, whether a given change in a service protocol changed the desired answer, etc.).\nA good introductory text is H.D Brunk Introduction to Mathematical Statistics ISBN: 0471008346 or (in spanish) INTRODUCCIÓN A LA ESTADÍSTICA MATEMÁTICA in Editorial Trillas; I'm sorry I don't have the ISBN for this).\nHOwever, any stastics text will do just fine.
985241
The answer is:\n\ne) You have no supporting evidence for any of the above conclusions.
803485
I think it's p=problem, i=infere' g=gather info? t=test e=expirement\n           good luck
112461
Aha! The liar paradox rears its ugly head again....\n\nThe asnwer is - neither true nor false. The propositional content and the semantic content of the statement contradict each other.\n\nTo unpick this paradox, you have to separate the statement from the proposition it contains. \nNote that the proposition has a positive truth value - it claims that "[yadda yadda] IS [bladiblah]"\n\nNow...\n\nIf the statment is true, the proposition that it contains is rendered false, leading to a self-contradiction.\nSo [This statement is false.] is false.\nBut if it is false that the statement is false then the proposition it contains is rendered true, and again the statement is rendered self-contradictory.\n\n(Repeat ad nauseum)\n\nIf you got that, ponder this one. It's a doozy:\n\n"This staitmennt contaynes three mistakes"
629585
not C or B, so it come to A, or D, a pvalue between 0.01-0.05 is generally considered strong evidence for alternetive hupothothes and against null hypotheses, A says same thing as choice C so D is the right anwer
815085
Not every problem should be solved with an elephant gun.\nJust ask yourself a different question. What is the probability that x2 is closer to x1 than to x3. since the answer to that question is the same as the question you ask and the only 2 possibilities are certain\nand mutually exclusive, the answer should be the same, 1/2.\n\nWhat about if x2 is exactly in the middle you ask?\n\nIt's like asking what is the probability that a random number in an interval is the midpoint. 1/infinity=0
245200
Proof by contradiction: Assume A or B.\n\nIf not B then not A\nalso not C (because of not B) so neither A nor C which contradicts our assumption. Therefore B.
268650
It is the assumption that nothing happened; that the treatment had no effect.\n\nFor example, suppose you were testing a headache relif.  You give on group sugar pills and the other group the medicine.  The null hypothesis is that the results for the sugar pill group were the same as the results for the medicine group (same number of headaches).  The alternate hypothesis is that the medicine group had a better result (fewer headaches).
524303
So X is dependent on TSOUT (the source of universal truth)\n\nAnd the TSOUT is dependent on X.\n\nThat, my friend, is circular logic, and as such, is a false proof.
929935
variations matter greatly in interpreting data.  Something might seem like it is returning significantly different results than the control but stat evaluation may show that the variations are minimal at best
238723
Because it's the only way to determine the veracity of a hypothesis.  The reason crackpot theories exist is because no one tests them.  I know people today who think that hot water will freeze faster than cold, even though common sense will tell you that the refrigerator will need to remove heat from the hot water to reach the same state as that of a tray of cold water.  Simple research will find that hypothesis is not true.
902600
Both statements are FALSE
176780
I have a different point of view to the post above. If the probability of the given event occuring is 0, the the probability P(A|B) is a nonsense sentence and undefined, in the same manner as division by 0. There's nothing wrong with the existence of meaningless statements.\nThe aforementioned probability being zero is only enforced if you change the probability space to that of P(A AND B) which can easily be argued to be zero.
1039620
Well, hypothesis is a possible prediction made from your observation.\n\nWish you all the best!