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    A What is first and Second order Dependence?

    Can someone please explain to me what it means what they say a model is "first and second order dependence?"
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    A What do significant autoregressive coefficients mean?

    I am building a business cycle index, which include 4 variables that drive the index. Each variable I also include autoregessive coefficients that are all significant and negative. I was wondering what is the significance of this? In other words, what is the significance of have autoregessive...
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    Testing of two means

    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.
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    Magnetic forces and particle of mass

    A particle with mass 1.81×10−3kg and a charge of 1.22×10−8C has, at a given instant, a velocity v =(3.00×104m/s)j^. produced by a uniform magnetic field B =(1.63T)i^+(0.980T)j^ Find the value of the expression qvB/m (the magnitude of a when v is perpendicular to B ), where q is the magnitude...
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    Magnitude and direction of Electric field

    Homework Statement Calculate the magnitude of the electric field E = (-11i^+14j^)N/C ∣∣E⃗ ∣∣ = _______ N/C Calculate the direction (relative to the +x-axis ) of the electric field E = (-11i^+14j^)N/C. θ =_________∘ counterclockwise from the +x-axis Homework Equations...
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    Book push Forces problem

    Homework Statement A 0.407 kg book rests at an angle against one side of a bookshelf. The magnitude and direction of the total force exerted on the book by the left side of the bookshelf are given by: Force Left = 2.17 Newtons and θ=59 degrees What must the magnitude and direction of...
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    Newton's Laws direction and acceleration

    Homework Statement Two forces are acting on a 0.250-kg hockey puck as it slides along the ice. The first force has a magnitude of 0.405 N and points 25.0° north of east. The second force has a magnitude of 0.565 N and points 75.0° north of east. If these are the only two forces acting on the...
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    Newton's second law clarinet problem

    A clarinetist, setting out for a performance, grabs his 3.41-kg clarinet case (including the clarinet) from the top of the piano and holds it in the air with an upward force of 31.8 N. Find the case\'s vertical acceleration. Indicate an upward acceleration as positive and a downward one as...
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    Projectile Problem

    Your gun's muzzle is at coordinate (0,1.12) meters and Your projectile hit the ground at coordinate (1.03,0) meters Compute muzzle velocity (vx): This is all I'm given to figure out the muzzles velocity, so I know I'm given a height and how much it moved horizontally. But I'm getting...
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    Motion's frequency

    A electric model train travels at 31.7 cm/s around a circular track of radius 1.73 m. How many revolutions does it perform per second, i.e, what is the motion\'s frequency? ______ Rev / s Find the train\'s period of revolution. ______ s This is how I worked out the problem: v^2/r = rw^2...
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    Initial value differential

    Problem: Find the solution to the initial Value problem (differential equations)? y'=-y+e^-2x y(0) = 3 Attempt: y' -y = e^(-2x) ----- (1) Linear equation of first order of form y' + y p(x) = q(x) p(x)= -1 q(x) = e^(-2x) Find the integrating factor e^∫p(x) dx = e^∫ - dx = e^-x Multiply...
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    Concept to differential equations

    Question: Explain why you cannot solve the ordinary equation? x^2y'' + xy' + (x^2-1)y = 0 My attempt: I don't need to solve it, but just simply state why I can't with just differential equations So my answer is, This differential equation does have a solution, it's just not expressable in...
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    Poisson Distribution Statistics

    Homework Statement If the number of complaints a dry cleaning establishment receives per day is random variable having the Poisson distribution with λ = 3.3, what are the probabilities that it will receive: (a) Five complaints altogether on any two given days. (b) at least 12 complaints...
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    Statistics! The gamma distribution

    Homework Statement Find the probabilities that the value of a random variable will exceed 4 if it has a gamma distribution with (a) \alpha = 2 and \beta = 3 (b) \alpha = 3 and \beta = 4 [b]3. The Attempt at a Solution [/b} how would I even attempt this question?
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    Unions and Intersections

    Homework Statement A and B are independent, P(A) = 0.30, P(B) = 0.50. Compute P(A U B) and P(A' intersect B). The Attempt at a Solution P(A U B) = 0.30 + 0.50 = 0.80 P(A' intersect B) = 1 - 0.30 = 0.70 this is obviously wrong
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    Probability Distribution

    Homework Statement Consider the experiment of tossing a fair coin 4 times. What is the probability distribution of the number X of heads? The Attempt at a Solution I got (0.5)(0.5)(0.5)(0.5) = 0.0625 but its wrong and I don't know why
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    Expressing the binomial coefficients

    Homework Statement Expressing the binomial coefficients in terms of factorials and simplifying algebraically, show that (n over r) = (n-r+1)/r (n over r-1); Homework Equations The Attempt at a Solution I honestly don't even know how to come about this problem...I really need help in this...
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    Matrix Algebra Transformation

    Homework Statement Let T: R3 → R3 be a linear transformation such that T(1, 1, 1) = (1, 0, –1), T(0, – 1, 2) = (–3, 3, –1), and T(1, 0, 1) = (1, 1, 0). Find the following expression. (Enter each vector as a comma-separated list of its components.) what is T(2, –1, 1)? The Attempt at a...
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    Parameterization of the Circle

    Homework Statement Consider the following parameterization of the circle: a) x1 (t) = (cost, sint) b) x2 (t) = (cos3t, sin3t) c) x3 (t) = (sint, cost) How long does it take point a particle to go from (1,0) to (0,1) for each parameterization. Homework Equations The...
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    Parameterizing a line

    Homework Statement Parameterize a line, L, such that is crosses through the point P=(3, -5) and direction v=(2, 8). Now, using this parametrization determine the following points belong to L: P1=(73, -180) and P2=(5, -14) Homework Equations The Attempt at a Solution I really need...
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    Parametrization question for my Intro. to Higher Math Class

    Two objects A and B are traveling in opposite direction on a straight line. At t=0 A and B are at positions P(A)=(-40, -20) and P(B)=(190, 980), respectively. If additionally, their paths are parameterized by directions V(A)=(3,5) and V(B)=(-24, -40), respectively. Then, a) find the point...