deviation Definition and 402 Threads

Hello, Upon following advice from BvU I'm starting a new thread to request help on a concrete issue I have. I have a container with 12x8 wells. Each well contains a roughly equal amount of bacteria. The bacteria are fluorescent, and I am trying to quantify their fluorescence as precisely as...

Homework Statement A business owner makes jars with weights that follow a normal distribution with a standard deviation of 8 pounds. In a random sample of 64 jars what is the probability that the sample mean differs from the population mean by no more than 1 pound? Homework Equations...

Hello, I have an experiment that I'm trying to conduct where I measure quantity A and normalize by quantity B. I then want to report normalized quantity A with error bars showing standard deviation. Quantity B is obtained via a standard curve that I generated (8 data points measured once each...

Hi, I've made a "probability" histogram for my data and it's based on 14000 datapoints in total, BUT each bin is not the same (e.g. bin 1 might be composed on 200 total datapoints while bin 50 is only 3 data points). You can find it in image 1. Now, based on those relative frequencies, I...

-3 SD -2 SD -1 SD 80 +1SD +2 SD +3 SD mean 65 70 75 85 90 95 The test has...

The book I am reading, Smith Van Ness Abbott has several figures of Pressure vs Composition for Vapor Liquid Equilibrium of a Binary system. It often includes a dashed straight line to represent Raoult's Law. What confuses me is that only the liquid phase ( P-x1 ) is said to exhibit...

My teacher of General Relativity has proposed a demonstration of the geodesic deviation equation based on normal coordinates, the problem is that for me the procedure is wrong, could you help me to find the problem? Suppose to have a differentiable manifold M of dimension 4, and two geodesics x...

In 2 dimensions, is the geodesic deviation equation governed by a single scalar, independent of the direction of the geodesics? That is, if ξ is the separation of two nearby geodesics, do we have d^2 \xi/ds^2 + R\xi = 0 where R is a scalar that is completely independent of the direction of the...

This is problem AP3.7 on page 669 of The Practice of Statistics, 5th AP Ed., by Starnes, Tabor, Yates, and Moore. A certain candy has different wrappers for various holidays. During Holiday 1, the candy wrappers are 30% silver, 30% red, and 40% pink. During Holiday 2, the wrappers are 50%...

When tossing a fair coin 1000 times a player correctly predicts 532 outcomes. Then I think I am right in saying that result is about + 2 Standard Deviations from the mean. sqr root 1000 x .5 x .5 = 15.81. 32/15.81= 2.02.However, if the results of the coin toss are given by a Net Gain/ Loss...

Homework Statement Minimal angle of deviation δm of light after passing through prism is connected with index of refraction n and inner angle of prism Φ: If index of refraction and inner angle of prism are directly measured, determine minimal angle of deviation, n=(1.52 ± 0.04) Φ=(30 ±...

Hi all, I have a question from a tutorial sheet that I'm stuck with. The question is Estimate the pressure at which a gas of argon atoms, at a temperature of 300 K, will begin to show deviations from the ideal gas behaviour due to the finite size of the atoms. Answer: Of order 10^9 Pa. So I...

Taken from my lecturer's notes on GR: I'm trying to understand what goes on from 2nd to 3rd line: N^\beta \nabla_\beta (T^\mu \nabla_\mu T^\alpha) - N^\beta \nabla_\beta T^\mu \nabla_\mu T^\alpha = -T^\beta \nabla_\beta N^\mu \nabla_\mu T^\alpha Using commutator relation ## T^v \nabla_v...

Homework Statement I am stuck on the last problem. Homework Equations Just the error propagation equations The Attempt at a Solution I initially used the multiplication error propagation formula. So the average force would be the impulse divided by the time, the same thing as the impulse...

In the last paragraph in Wald p. 224, he states that if one considers a timelike geodesic ##\gamma## with tangent field ##\xi## and ##p \in \gamma## and now looks at the congruence of geodesics passing through ##p##, then every Jacobi field which vanishes at ##p## is a deviation field for this...

I'm trying to understand the derivation of the expression for the random Brownian force on a particle in a medium with coefficient of viscosity η. It turns out it is gaussian over some timescale, with a standard deviation that depends on the temperature and the viscosity. I'd like to read a...

Homework Statement "Consider a standard uniform density. The mean for this density is .5 and the variance is 1 / 12. You sample 1,000 sample means where each sample mean is comprised of 100 observations. You take the standard deviation of the 1,000 sample means. About what number would you...

Homework Statement Write down the Newtonian approximation to the geodesic deviation equation for a family of geodesics. ##V^\mu## is the particle 4-velocity and ##Y^\mu## is the deviation vector. Homework Equations D = V^\mu\nabla_\mu \\ V^\mu\approx(1,0,0,0) \\...

Homework Statement A bullet (3.40g) has a velocity of 160m/s perpendicular to Earth's magnetic field 5x10^-5 T . The bullet has a charge of 13.5 x 10^-9 C.With what distance will it be deviated from its trajectory after it has traveled 1.00km? Homework Equations...

Given a one-dimensional Gaussian distribution, distributed as following: f (x) = exp (-x ^ 2 / (2q)) / q / √ (2pi) proof which q is the standard deviation Thanks !The standard deviation is defined by: http://www.mathsisfun.com/data/standard-deviation-formulas.html

I did the problem but none of my answers match up with the answer choices so I'm obviously doing it wrong. Can someone show me how to do these two problems. I have a test coming up and I am so behind For women aged 18-24, the systolic blood pressure (in hg mm) are normally distributed with a...

Homework Statement in the first photo , the direction of x-ray and the atomic plane are shown. whereas for the 2nd photo , the the direction of x-ray and the atomic plane are not shown... so i would assume the glancing angle = 0 . beacuse the atomic plane is parallel to the x-ray ...but in the...

Say if I have a sample space 2,3, and 5. I want to find by what percent points deviate from the mean. So I would take the standard deviation as follows. 2+3+5 / 3 = 3.33 (2-3.33)^2 + (3-3.33)^2 + (5-3.33)^2 / 3 = 1.55 (1.55)^(1/2) = 0.775 So we get a standard deviation of 0.775. So how do I...

Homework Statement How does skew and range affect the standard deviation; does one affect it more than the other? Homework Equations None The Attempt at a Solution It seems as though if the range increases, the standard deviation increases because the SD is a measure of how spread apart...

hi (Wave) know its a big jump from calc 3 down to stats but i can't remember how to get the standard deviation. I am given this table and I am asked to find the standard deviation. can i please get a step by step solution? thanks (Blush)

Homework Statement There are 55 independent normal observations with mean 100. The first 50 observations have variance 76.4 and last five have variance 127. Calculate the probability that ##\bar{x}=\frac{1}{55}\sum_{i=1}^{55} X_i## is between 98 and 103. Homework Equations The Attempt at a...

On the surface of a unit sphere two cars are on the equator moving north with velocity v. Their initial separation on the equator is d. I've used the equation of geodesic deviation...

Light traveling transverse to a massive body (e.g. Sun) is deviated by an angle twice the amount predicted by Newtonian gravitational theory. This is predicted by GR and proven experimentally. What would be the deviation of a matter particle traveling near c transverse to a massive body...

I need to prove that $$std(x+c) = std(x)$$ I have been trying to use the properties of the mean such as $$mean(x+c) = mean(x) + c$$ I am confused on the following property of the mean, is this statement correct? $$\sum\limits_{i=1}^{i=N}(x_i - mean(\{x\}))^2 = mean(\{x\}) \\$$ If that is...

Long time no post... I am very much disturbed after my research of measurement errors and corresponding norms, because I find so few results. There are mainly two ways to specify errors of measurement instruments. Standard deviation with its siblings and maximum error. I am a great fan of...

Hello, I don't know how the figure on the image posted works. If a grade is averaged at a B, which does this figure indicate my letter grade is? Is each box a standard deviation?

Definition/Summary Where two particles very close together have the same velocities, their two geodesics are parallel, though only instantaneously, and so the gap (a 4-vector, of time and distance) between them has zero rate of increase, but has non-zero acceleration. The acceleration (a...

my question is on part ii, my range ( as shown in the photo), is between 4.52 and 16.28, so my working would be (6+10+4+4)/(6+10+4+4+1) X100% ... the answer given is 72% which is differnt form my answer? which part of my working is wrong ?

Consider an inertial frame where an electric current is flowing in upward direction, a magnetic field is created and its direction is determined by the right hand rule. In the frame of reference of the electric charges which they are at rest, how can the observer in that frame explains the...

I've been meaning to ask this for some time, and now I've plucked up the courage! It is puzzling to me that many fundamental relationships in GR are explained in terms of euclidean space. Taking for example the geodesic deviation equation, it occurs to me that if defined in 3+1 spacetime there...

What is the significance of the standard deviation (equal to the mean) in an exponential distribution? For example, as compared to the standard deviation in the normal distribution, which conforms to the '68-95-99.7' rule? thanks

1. Dear all Hello My name is Shamim and I am a student in high school and having 15 years old. I am a newcomer in this forum. I have found this great forum from internet while I was searching into that. I am really interested too much to physics and actually trying to learn more about that. I...

If thermodynamic temperature can be interpreted as the average kinetic energy in a system, is there a quantity defined as the standard deviation? For example, let's say you poured some hot water into a cup of cold water. The instant you poured it the standard deviation of the system would be...

Homework Statement Here is a slide in my notes: I am kind of confused about mean and standard deviation. So in my notes it says X1 to Xn are independent measurements. Then it says each independent measurement has a mean μ. But how is this possible, if they are independent measurements (in...

In some textbooks ##\Delta \hat{x}## is called dispersion of coordinate ##\Delta \hat{x}=(\langle \hat{x^2} \rangle-\langle \hat{x} \rangle ^2)^{\frac{1}{2}}##. For me that is standard deviation. What do you think?

Homework Statement For a certain random variable X, P(X≤500)=.5 and P(X>650)=.0227, find σ. Homework Equations μ=expected value=mean Variance=∫(X-μ)2fx(X)dx evaluated from -∞ to ∞ σ=√Variance The Attempt at a Solution I'm not sure what the relationships between the...

After filling out the table, I used it to finally calculate the standard deviation as 0.105. Just to make sure, I ran it through Microsoft Excel and got 0.942809042. I put two together and figured I'm doing something wrong after the xw column because Excel agrees that the mean is also 1.7...

Hello, PF! [My question pertains to a non-rigorous, undergraduate introductory Probability and Statistics course. I'm no math major, so please correct me if I've mishandled any terms or concepts as I try to express myself. I'm always eager to learn!] * * * In a discussion of the...

Phase modulation is a system in which the amplitude of the modulated carrier is kept constant, while its phase and rate of phase change are varied by the modulating signal. By the definition of phase modulation, the amount by which the carrier phase is varied from its unmodulated value, called...

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...

Hi,,,can u please explain me how to calculate standard deviation and standard error for a binomial distribution when you have several samples? For exapmple: I don't know the population size. I take a sample of 10 and check for a particular characteristic. Let's say number of successes for this...

I had this problem on a quiz and obviously got it wrong, I am confused about how to set this question up and what to solve for: In a large city, the average retail price of a pound of grapes is $1.79, with a standard deviation of 18 cents. Between what values must be the price of at least 15/16...

I'm having an issue in comprehending the minimum deviation offered by a prism. The fact that we could use the symmetry argument about the angle of incidence and angle of emergence being equal for minimum deviation make sense to me but I couldn't understand why we can be so sure of exactly 1 such...

Hi guys, I hope someone is able to help me with this, I'm currently stuck on a problem. 1. I was given some data (in continuous, grouped form) regarding phone call times for a call center agent and asked to represent the data using the most accurate form of average. I initially calculated...

Hi guys, I hope someone is able to help, I'm currently stuck on a problem. I'm having trouble justifying which representation is more accurate for my data; either mean with standard deviation or median with IQR. I've calculated both averages for the my data, however I was advised by someone...