Statistics Definition and 998 Threads

Let me preface this by saying that economist Gregory Clark argues in "A Farewell To Alms" that one of the factors for the success of the industrial revolution was evolutionary in nature: disease killed off poorer members of the society and their position was taken over by sons of the wealthy who...

Homework Statement Hi, I'm having some problem with one of my final exam study questions, and I'm hoping someone can help me out a little. here is the problem: Let Y_{1},Y_{2},...,Y_{n} denote random samples of numbers from a uniform distribution on the interval [0,1]. Denote the...

[SOLVED] Quantum Statistics question Homework Statement Electrons in a metal are considered as free electron gas where (a) Fermi energy is (h^2/2m)[3N/8*pi*V]^(2/3) (b)Average energy of the free electrons at absolute zero is E(0)=(3/5)E_f where E_f is the Fermi energy (c)Pauli...

i was put in this class and I am 14 and i seriously need some help on this topic Die A has four 9's and two 0's on its faces. Die B has four 3's and two 11's on its faces. when either of these dice is rolled, each face has an equal chance of landng on top. two players are going to play a...

Springfield Football Club plan to field a team of 3 forwards, 4 mid-fielders and 3 defenders and a goalkeeper. Assuming they have 8 forwards, 6 mid-fielders, 5 defenders and 2 goal- keepers on their books how many teams can they make? i tried doing: (8C3) x (6C4) x (5C3) x (2C1) but...

Homework Statement Basically the garbage information summed up: a truck is transporting a bunch of batteries, with lots of different brands. The truck crashes and the batteries and scrambled. Suppose the number of pairs of batteries is n. Each pair is a different brand. If 2r batteries are...

Sir Kindly arrange to provide the detailed notes for the following questions. 1. When is it appropriate to use the uniform distribution to describe a random variable X? 2. Why do we compute values when using the normal table? Explain. 3. Explain the meaning of the height of a...

I have the data set # of freights - probability 1 - .075 1.5 - .025 2 - .425 2.5 - .150 3 - .125 3.5 - .100 4 - .050 5 - .025 6 - .025 The question is, what is the probability that at least 5 of 6 families purchased more than four freights. I started with making a graph of the...

1. Homework Statement (I forgot to write out the problem statement in previous post) How do California H.S. students compare to students nationwide in their college readiness, as measured by their SAT scores? The national average scores for the class of 2003 were 507 on the verbal portion...

Homework Statement a. Do the data provide sufficient evidence to indicate that the average verbal score for all California students in the class of 2003 is different from the national average? Test using alpha = .05. b. Do the data provide sufficient evidence to indicate that the average math...

Suppose we have particles of kind B, that consist of two fermions of kind F. Now the particles B satisfy the Bose statistics. But what precisely does this mean? If we have four F particles, the system is described by a wave function \psi(x_1,x_2,x_3,x_4) Suppose the particles 1 and 2...

based on the data from the census bureau, when a woman over the age of 25 is randomly selected, there is a 0.218 probability that she has a bachelor degree. if a woman over the age of 25 is randomly selected, find the probability that she does not have a bachelors degree help this. Thankyou

how many distinct positive integer- valued vectors (x1 , x2 , . . . , x6) satisfying x1+ x2+. . .+x6 = 12 if 2 of xi must be = 1 ? please help this question book: A First Course in Probability (7th) by Ross

My friend came up with some solutions but I have doubts about them and was wondering if someone could help a bit. Homework Statement A committee of 4 people is randomly selected from 5 married couples. What is the probability that a husband and wife do not belong to that committee? The...

The problem goes as such; The scale of scores on an IQ test is approximately Normal with mean 100 and standard deviation 15. The organization MENSA, which calls itself "the high-IQ society," requires an IQ score of 130 or higher for membership. What percent of adults would qualify for...

Hello, I'm looking for some sort of velocity time graph/table, which illustrates how a car accelerates in a range of 5 seconds or so. I'm trying to figure out at what point the car's acceleration will be higher than a runners acceleration. (It's only a matter of time before the car can overpower...

Homework Statement A telephone survey is planning a marketing survey of its 760000 customers. For budget reasons, the company wants a sample size of about 250. a) Suggest a method for selecting a systematic sample.? b) What expense do you think is most likely to limit the sample size...

Where can I find a very detailed statistics about graduate school (Including books or websites), which includes the average GPA, GRE Scores of the entering applicants (Major wise), the population, available majors, etc.

These are some of the most entertaining and interesting presentations on world poverty I've seen. I think most if not everyone here would find them quite fascinating. http://www.ted.com/index.php/talks/view/id/92 http://www.ted.com/index.php/talks/view/id/140 enjoy.

In what kind of experiments does the fermi statistics show? What kind of experiments have been carried out to verify that electrons obey fermi statistics? This fermi statistics stuff has been quite theoretical only in texts I have encountered so far.

Homework Statement I'm absolutely desperate for help on this. The image supplied below is an image of a frequency histogram for the V-band Tycho photometry data (from the Tycho Epoch Photometry Annex). What I've done is this: 1. I've converted the V-band magnitudes into flux so that it is...

1. A study of zinc-deficient mothers was conducted to determine whether zinc supplemnetation during pregnancy results in babies with increased weight at birth. The weights are measured in grams. Use a 0.05 significance level to test the claim that zinc supplementation does increase weight at...

Hi, I'm taking a distance learning course in statistics so there are a few concepts that are not clear to me. First I was wondering if it was possible to add up Z scores. I have a problem in which two students have two different z scores on two exams. Peter has 1,69 on the first one and -0,13...

I was just curious if anyone here knew the statistics on the average time it takes to get an engineering degree?

I am having an interesting discussion on a newsgroup (alt.assassination.jfk) regarding the single bullet theory (SBT) from the JFK assassination. The problem with the SBT is that it conflicts with much of the evidence. The current SBT to which most SBT adherents subscribe (e.g Gerald Posner in...

Back in 2002, Lubos Motl wrote a paper on Title: An analytical computation of asymptotic Schwarzschild quasinormal frequencies Lubos Motl, Adv.Theor.Math.Phys. 6 (2003) 1135-1162 Recently it has been proposed that a strange logarithmic expression for the so-called Barbero-Immirzi parameter...

out of me being too poor/cheap to buy my stats txt book, I'm running out of problems to do while studying for exams. anybody know of any good websites that may have some practice problems for a second year engineering stats course. we just covered the basics. distributions, likelihood...

Homework Statement The problem: An airline always overbooks, if possible. A particular plane has 95 seats on a flight and the airline sells 100 tickets. If the probability of an individual not showing is 0.05, assuming independence, what is the probability that the airline can...

I have some statistics on a test from my biology class and I was wondering if there is enough information provided by the stats to be able to calculate the average of the top 5% of scores. I have used a graph in mathematica to get a pretty good idea of what the top 5% average is, but I was...

Homework Statement Evaluate the integrals (eqns 5.108 and 5.109) for the case of identical fermions at absolute zero. Homework Equations 5.108 N=\frac{V}{2\pi^{2}}\int_{0}^{\infty}\frac{k^2}{e^{[(\hbar^{2}k^{2}/2m)-\mu]/kT}+1}dk 5.109...

Homework Statement The bank is opened from 9:00 to 17:00. From 9:00 to 10:30 the average client count who come into bank is 32/hour, from 10:30 to 15:30 it is 26/hour and from 15:30 to 17:00 it is 50 clients per hour. I have to test the hypothesis that the average count of clients who...

Homework Statement In a recent survey, 80% of the community favored building a police substation in their neighborhood. If 15 citizen are chosen, what is the standard deviation of the number favoring the substation? Homework Equations I know that my mean is 15 and the probiblilty is 80...

Homework Statement Suppose that a dietitian has 3 groups of foods, having 5 items in the first group, 7 items in the second group and 2 items in the third group. 1. How many meals are possible containing one food from each food group? 2. How many meals are possible containing 3 foods from...

Hi all, I was just wondering which would be the more beneficial first year uni subject to take given that I would like to major in either chemistry or physics - Discrete Mathematics or Statistics. The Discrete maths course "focuses on the enumeration of the Catalan Numbers" and is an...

I've been curious as to why Bose-Einstein statistics are always derived using the grand canonical partition function. Yes, I know it is easier, but there must also be an expression for the canonical ensemble. However, I was suprised that I have been unable to find it in the standard sources -...

Homework Statement This is my data: 42.4, 65.7, 29.8, 58.7, 52.1, 55.8, 57.0, 68.7, 67.3, 67.3, 54.3, 54.0 I need to find the standard deviation of this list of data. 2. Homework Equations standard deviation= : s^2=\frac{\sum_{i=1}^n(x_i -\overline{x})}{n-1} Actually the standard...

Just read http://www.alertnet.org/thenews/newsdesk/N19303337.htm", which conveys the message that the war in Iraq is going so badly, that the suicide rate has doubled. However, this is simply a Poisson distribution, and the values they list do not seem to indicate that the mean value has...

Homework Statement (a) Find the average energy per photon for photons in thermal equilibrium with a cavity at temperature T. (b) Calculate the average photon energy in electron volts at T = 6000K.Homework Equations u(E)dE = \frac{8 \pi}{(hc)^3} \frac{E^3 dE}{e^{E/k_B T} - 1}The Attempt at a...

Homework Statement Harley-Davidson motorcyles make up 14% of all the motorcyles registered in the United States. You plan to interview an SRS of 500 motorcyle owners. a) what the approximate distribution of the proportion of your sample who owns harleys? b) Is your sample likely to contain...

I've got nine sets of data (three people each took ten measurements of three different distances), and I need to find an estimate of the accuracy to which each person measured each distance. I've already calculated the mean and standard deviation for each set of data, but I don't know how to...

30) A special roulette wheel has seven equally likely outcomes: 0, 1, 2, 3, 4, 5, 6. If you bet that an odd number comes up, you win or lose $10 according to whether or not that event occurs. If X denotes your ‘net’ gain, X=10 if we see 1, 3, or 5, and X = -10 otherwise. Suppose that you play...

Homework Statement Consider a classical particle moving in a one-dimensional potential well u(x). The particle is in thermal equilibrium with a reservoir at temperature T, so the probabilities of its various states are determined by Boltzmann statistics. Show that the average position of the...

I guess this should properly go in the Programming forum, but I think I might get a better response here. My question is with respect to statistics (context of machine learning) about "over-searching" error. You have a search space S of all possible models, from which you choose a subset K...

alright i juz want to say I am stucked in examples problem, the question is: A semiconductor is said to be degenerately doped when n>-Nc or p>-Nv. assuming Maxwell Boltzmann statistics, determine the values of Nd and Na needed to obtain degenerately doped N- and P- type silicon. Where is the...

Is there a good statistics book that is the equivalent of Stewart for Calculus in terms of level and theory? I am probably going to retake stat in the math department at some point (or not), but want to know if such a book exists. By and large, the stat books I have thumbed through are garbage.

For a sample of 100 wheat fields, the mean yield was 10 tons/acre and the standard deviation 2. Approximately how many fields out of the 100 should have yields in the 8 to 12 ton range? Show work.

Just curious what people's campus crime statistics are this is from UAF in Fairbanks, Alaska http://www.uaf.edu/police/crime.html Alaska has a liquor problem, no?

Hi there, This question is giving me some trouble... 1.1-6 A game consists of rolling a pair of dice and moving a game piece the number of spaces according to the total number of dots on the dice. In order to move the game piece on a player's first turn, the player must roll a 1 or a 6...