Testing Definition and 589 Threads

Homework Statement Given that 8 person vote for Mr Tan , i can't understand why the probability is sum of 0 people vote for him until 8 people vote for him. Why not the probability = 22c8 ( (0.6)^8 )( (0.4)^14) ? Homework EquationsThe Attempt at a Solution

Hi I'm working on something where the sample size is less than 10 and I know the population mean and standard deviation. When using the T test most of the examples I find calculate the standard error from the sample standard deviation but these are cases where the population standard deviation...

I had a piece of box section steel tubing, 400mm long, 5 x 10cm section, 3mm thick. It has a foot welded to the bottom which stabilises it at the floor (this is in red). It is a weight lifting bench. I needed to shorten the length, so I cut it in two and overlapped a join, then fixed it with 3...

Y: 51 32 30 74 42 35 39 33 55 61 Y-hat: 49 35 29 72 44 32 38 36 57 60 Null hypothesis: mean y-hat = mean y Alternative hypothesis: not null hypothesis So I got as a t test 0 and I was wondering if I did something wrong because I never has this case happened to me.

I read that I can use the hypothesis testing technique for proportions to decide whether the number of levels for a design variable could be reduced. In literature the following typical test was used: Ho: pi=0 Ha: pi
\neq0 where pi is the proportion of class i (level i ) within the...

greetings to all, I'm a member of the quality department of a company in the automotive industry. We test all kinds of materials related to welding and we are required to perform serten tests according to standards... we have however a functional problem during testing of the torque on...

Thought experiment: Alice, Bob, and the planet Zolan. Alice is floating in space 10 light seconds from the planet Zolan (Z) with a radio emitter and detector. She and planet Z are in the same rest frame. Bob has the same devices as Alice but is on planet Z. Bob then accelerates from...

This may be a stupid question, but have the various gravitational wave observatories around the world been tested by seeing if they can detect man-made gravitational waves, and thus work as expected? Or would it be too unfeasible to make them, even given the extreme sensitivity that the...

Hello everyone. I am trying to use a Faraday cup constructed by myself to measure the electrostatic charge presence in particles of a fluidized bed reactor. I am trying to test if it works properly but I am having some problems. I am tried to apply a voltage of 1.5 V till I obtain that...

Depending on who one asks and their interpretation of QM, entanglement seems to be either: a) No problem at all. It's just a matter of information. If you knew one entangled electron was spin up, then the other must have been spin down by inference of the prepared state of the system. b)...

Deta Elis are a Russian company which provide well being devices based on the work by Paul Schmidt and Royal Raymond Rife. They have clinical studies and patents. Does anyone know of a low price resonance frequency analyser which could read the frequencies emitted and possibly test these devices?

Hello :) I am Jon and I am conducting an experiment with Quartz Crystals to test their piezoelectric properties. I wanted to ask you a question about my experiment set up. Which type of force is required to be applied for voltage to be produced? Could I apply a compressive force with...

Hello there, I am having a discussion with a co-worker about a pressure drop test. I have two different 'boxes' for which I don't know the pressure drop. What I want to know is the difference in pressure drop between the two 'boxes'. Knowns 1) PA1 = PA2 = PA = Inlet Pressure for...

I have a drag car I'm wanting to do some testing on . Would anyone mind giving me some insight. A Pm or on here is fine. thanks.

Hello Guys, I have been doing Charpy tests for the past couple of months and notice that I can't get rid of the water that keeps freezing and sinking to the bottom of the my chiller. It's becoming more of a hassle that my agitator stops due to the water freezing at the bottom of the chiller...

Homework Statement For example in my notes in class the prof went over an example with the following null and alternative hypothesis: I feel like you can switch them around but I am not too sure. I have been trying to figure out when to use greater than or less than for the null...

Hi guys, So say I want to perform tensile tests on a bolt, but want to see what the effect of applying the load at various angles to the axis of the bolt would be. It's kindabutnotreally a shear test... I realize that if I had complete knowledge of the material properties of the bolt I...

Can someone please give me a bit of advise. I was dealing with impact toughness of materials today, which I haven't dealt with since uni days. I was involved in charpy testing. I understand the concept of finding the impact toughness from the test [ m x g x (h2 - h1) ]. But what I can't get my...

Something I've wondered about the Double Slit Experiment is what happens to photons which fail to pass through either slit, and what is their behavior? Why not put some detectors on the source side of the slits during a double slit experiment to try to determine whether the photons are...

I was a member here years ago and recall the excellent quality of the brain trust present and I need some brain power to give me some understanding of the situation I find myself in. Through a series of unfortunate events, the woman I was seeing had a brief encounter with another man. Here were...

Hi, What I know: In a hypothesis test for the mean, we compare a sample mean with a hypothetical sampling distribution of means. And depending on how far it is away from the mean of the sampling distribution, we attribute it the probability of getting that value purely by chance. What I...

Hey guys. I have some trouble understanding how the F-test is used for testing the viability of a regression model. Before I delve into the background/question, just wanted to post a link that discusses the topic briefly: http://www.stat.yale.edu/Courses/1997-98/101/anovareg.htm So, coming...

Hi there I want to come up with an experiment to test two accelerometers to see how much they vary. I was thinking about dropping them each from a height but I am unsure how I could then work out what values I should be getting. Also does it matter what height I drop them from as I realize it...

Homework Statement By considering its divergence, test whether the following vector field could be a magnetic field: F=(a/r) cos∅ r Where a is constant. NOTE( the 'r' has the hat symbol ontop if it, unit vector i think) Homework Equations You may use that is cylindrical...

In a sample of 100 people. 50 people like ice cream, of those 50 people, 25 like chocolate. Calculate with 95% confidence, that over 60% of people like his chocolate ice cream. H_0= mu > 0.60 H_1=mu < 0.60 25/50=0.50% of people like chocolate ice cream (0.50-0.60)/...

How much is it feasible for us to send some probe/s to the event horizon of a black hole? Perhaps Voyager will arrive at the centre of our galaxy, where if I remember correctly there's a massive black hole. How much time will that take? Probably Voyager will collapse way before arriving at...

So I took an elective in environmental science and the professor puts stupid trivia questions on her tests/quizzes to prevent people from getting 100 on her course. For example from one of her online quizzes: she asks what percentage of air pollution is caused by motor vehicles. Or another...

Homework Statement I am trying to make sure I am using the Weierstrass test correctly. So, on the following expression: $$f_n(x) = \frac{x}{1+nx^2}, -1 \le x \le 1$$ I looked at it this way. First I checked to see what happens at -1 and 1. The "plug in" test gets me a limit of 1/2 at x=1...

I have an absolute love for chemistry particleurly analytical and organic. my problem is I'm not the greatest when it comes to math as i never was granted the opertunity for higher level math classes in grad school. I'm the first in my family to actually graduate high school. I tested into math...

I have a verilog code for a simple 8-bit counter. I'm trying to build a testbench but for some reason it doesn't work. I'm using xilinx and when I run the simulation, the inputs work but the output doesn't work. It stays as XXX. Here is my verilog code and testbench. module counter(enable...

Homework Statement I'm looking through some example problems that my professor posted and this bit doesn't make sense How do you come up with the values underlined? Homework Equations The Attempt at a Solution Upon researching it, I find that you should use α/2 for both...

Kochen-Specker rules out non-contextual hidden variable theories and Bell's theorem rules out local theories. I thought this was an interesting paper, particularly the authors' conclusions: Simultaneously testing the Kochen-Specker and Bell theorems http://arxiv.org/pdf/1308.6336.pdf

I have an electrochemical cell I need to get testing done on (namely cyclic voltammetry). Problem is, I have no idea where to go? Any suggestions? I was thinking of contacting the local State University Chemistry department but I doubt it if they would do testing for someone who is not a...

What is a good test for hypothesis testing of a complex deterministic model? What I'm doing: I have a complex system of nonlinear differential equations. I must solve them numerically. There are about 22 input parameters that I have rough physiological ranges for and I use a genetic...

Take for example a human being inside a wooden crate. One can not see, taste, touch, smell or hear the human inside the crate, or whatever it is being tested against. We know roughly the outer dimensions of the crate giving an upper limit to the size of the human being within plus or minus a...

Testing for chaos in data I have data for 3 variables ,each with respect to the discrete time values. How do I check for the existence of chaos for this discrete 3D system?(I don't have the analytic eqs.,just the data.) MY IDEAS ON CHECKING FOR CHAOS FROM DATA:(which of these are feasible...

Hey guys, I know what polynomials are but what I really don't understand is the way you are able to find the equation to a set amount of points. I don't understand why you have to have a certain amount of points to find different degrees of functions. For example, why are only three points...

Here is my circuit I'm trying to double the frequency of my input to my output. k = 1/10 V For example: input is VmSin(2\pi1000t)/10 Vo = (VmSin(2\pi1000t))^2/10 Output should be Vm^2/20 + Vm^2cos(2\pi2000t)/20 My oscilloscope isn't picking up on the doubling, so I know my circuit is...

I'm testing an algorithm to find the global mimina of a function. Can someone give me a few examples of optimization test functions in 2 or 3 dimensions, like the Rastrigin function. I'm hoping to find functions with several local minima.

Hi, I am trying to teach myself how to test hypotheses for any distribution, but am having some trouble. X=number chosen each year θ=Mean number chosen in the population H0: θ=.5 h1: θ>.5 The random sample of n=4 is 0,1,3,3 Test the Hypotheses at α≤0.05 assuming X is a...

Hi, I'm looking at a question which asks how one can test for ammonia in [NH4]2Fe[SO4]2 The answer says that you add sodium hydroxide, and get [NH4]2Fe[SO4]2 + 2 NaOH -> [NH4]2Fe(OH)2 + 2 NaSO4 This is what I don't get: it then says you test the ammonia gas with litmus paper, or with HCL...

What is the difference between ESD and EFT compliance testing. EFT is continuous and ESD is not?

Linear Model topic: Given that we have a crossed fixed model w/o interaction, how would I go about testing for the main effects using extra (seq) sum of squares? I know I am supposed to somehow use the F test and get the non centrality parameter but I don't know how to start... Thanks!

I had read that water is essential for any acid. When HCl is dissolved in water, it produces H+ ions which cause the litmus paper to change it colour! But if HCl gas is liquidified and then tested with liquid, what would be the results? As wel as this pure liquid HCl is corrosive or not?

Homework Statement We sample a population 50 times with replacement, with all individual sampled equally likely. We survey the gender and quality of life. The counts are: Male: 13 high quality, 11 low | female: 18 high, 8 low. Let P_M, P_F, P_H, P_L to denote these population proportions for...

This is the question: Suppose that X1...Xn form a random sample from the Bernoulli Distribution with unknown parameter P. Let Po and P1 be specified values such that 0<P1<Po<1, and suppose that is desired to test the following simple hypotheses: Ho: P=Po, H1: P=P1. A. Show that a test...

Hi, i have been doing a science project about radiation of smartphone functions. I have tried to use a EM wave receiver to measure the frequency of RF but it didn't work.How can i measure it (in hertz)?

Homework Statement The Electric field lines in an X-Y plane are given in the attached image. The field is defined as E=αi(vector)y at x=0 and x=some distance along the positive X axis. α is a positive constant. Test for charges in the X-Y plane Homework Equations N/A The Attempt...

How can you test an area for radium cheaply, and how can you test your body for exposure. In other words how would you test a room? And what types of tests could you get yourself?

Homework Statement This is not a homework problem, rather it is a conceptual question. I am wondering if the below is an accurate illustration to explain why I reject the null hypothesis. Such that H_{0}: \mu=\mu_{0} H_{a}: \mu\ne\mu_{0} By relating the reasoning with the diagram...