Threshold Definition and 131 Threads

The electoral threshold, or election threshold, is the minimum share of the primary vote which a candidate or political party requires to achieve before they become entitled to any representation in a legislature. This limit can operate in various ways. For example, in party-list proportional representation systems an electoral threshold requires that a party must receive a specified minimum percentage of votes (e.g. 5%), either nationally or in a particular electoral district, to obtain any seats in the legislature. In multi-member constituencies using preferential voting, besides the electoral threshold, to be awarded a seat, a candidate is also required to achieve a quota, either on the primary vote or after distribution of preferences, which depends on the number of members to be returned from a constituency.
The effect of an electoral threshold is to deny representation to small parties or to force them into coalitions, with the presumption of rendering the election system more stable by keeping out fringe parties. Proponents note that simply having a few seats in a legislature can significantly boost the profile of a fringe party; and that providing representation and possibly veto power for a party that, say, receives only 1% of the vote, may not be appropriate. However, critics argue out that in the absence of a ranked ballot system, supporters of minor parties are effectively disenfranchised and denied the right of representation by someone of their choosing.
Two boundaries can be defined—a threshold of representation is the minimum vote share that might yield a party a seat (under the most favorable circumstances for the party) while the threshold of exclusion is the maximum vote share that could be insufficient to yield a seat (under the least favorable circumstances). Lijphart suggested calculating the informal threshold as the mean of these.

View More On Wikipedia.org
  1. K

    What is the Threshold Energy of a Proton Beam to Produce 100 GeV Pions?

    Homework Statement I am trying to find the minimum energy for a proton beam to make pions that have 100Gev of momentum. The proton beam is hitting a fixed target. Homework Equations p + n -> n + n + ##π^{+}## The Attempt at a Solution In the centre of mass frame, there is zero...
  2. O

    Find energy threshold from a proton collision

    Homework Statement Two photons collide and create an electron-positron pair: y1+y2 -> e-+e+ If the wavelength of y1 is 1 mm calculate the energy threshold for photon y1 to produce the electron-positron pair. Suppose E(y1)=hc/\lambda2 where \lambda2 =1.1 mm Hints: In the center of...
  3. E

    Photon + proton collision & threshold nrg

    Could anyone guide me through this problem? https://www.physicsforums.com/showthread.php?t=348863 Just need to get started. Note that this would need to be solved in the proton rest frame.
  4. M

    MHB Inflection Point of the Threshold Equation

    Hello all, This is probably a simple question, but for some reason no matter how much I fight these figures I can't seem to make it work out correctly. $$y' = -r(1-\frac{y}{T})y$$ $$y' = -ry + \frac{ry^2}{T}$$ $$y'' = -ryy' + \frac{2ryy'}{T}$$ $$0 = -ryy' + \frac{2ryy'}{T}$$ $$ryy' =...
  5. J

    Extremely energetic photon threshold

    Does anyone have any information regarding if a photon will at some point obtain mass at huge energy amounts? Let's say perhaps the photon gains so much energy that it's wavelength reaches Planck's length, is it possible that it would gain mass? Is there any information regarding this inquiry...
  6. U

    Relativistic collisions - different frames, threshold energy

    Homework Statement (a) Show that E2 - p2c2 is a Lorentz invariant, where E is the total energy, p is the momentum, c is speed of light. (b) In the lab frame, an utlra-relativistic electron with γ = 100 collides head-on with a photon of energy E. Find the threshold energy E required to...
  7. T

    Does intensity of photons affect threshold frequency?

    If energy is kept constant and intensity of photons is increased, will the threshold frequency be lowered? I ask because I'd like to understand this graph - http://www.flickr.com/photos/coachrobbo/3909285882/ "lower intensity same frequency" causes stopping voltage to be lowered, thus...
  8. Greg Bernhardt

    News Should the US drunk-driving threshold be lowered?

    Sounds ok to me. If I have more than two drinks, I don't drive. When I'm out on a weekend I see far to many people get behind a car when they shouldn't. We also need to make the punishments more severe. I hear of many reports of people with 3-4-5 DUIs still with a license or still driving...
  9. A

    Threshold, proton-proton-collision

    Hello, I regard a proton-proton collision. (Target at rest.) Here accrues a K^{+}(494) -meson. I want to callculate the threshold energy. But I think for callculating the threshold I have to know all participant of the product. Can i assume, that the protons will not be destroyed...
  10. K

    How Far Can You Hear the Siren at 2400 Hz?

    The sound level from a siren emitting sound with a frequency of 2400 Hz is 75.0 dB at a distance of 47.0 m from the siren. Assume that the intensity of that sound obeys the inverse square law. Calculate how far from the siren a person, with a threshold of hearing of 36.0 dB at that frequency...
  11. G

    Sound Intensity and Threshold of hearing

    My textbook says that in the equation β= 10log(I1/I2), I1 in most cases is the threshold of hearing (1.0x10^-12). Just out of curiosity, when is I1 not the threshold of hearing?
  12. J

    Testing Signals Above Threshold Voltage Non-Programmable

    Greetings, I have two signals, I need a way of testing whether they go above certain threshold voltages for a period of 0.5 seconds. This must be non programmable. I am a bit stumped o how to do it. I thought of having these signals go into an AND gate and then have that AND gate feed into...
  13. O

    Threshold voltage dependence on Vdb

    Why does the Vth of MOSFETs depends on Vsb and not Vdb even though MOSFETs are symmetrical devices? Is it a convention to choose Vsb over Vdb or am I missing out on something more fundamental?
  14. U

    Calculate the velocity of the centre of mass at threshold

    Homework Statement A high-energy photon γ1 of energy 261 GeV collides with an infrared photon γ2 of energy 1eV to produce an electron-positron pair via the reaction γ1 + γ2 → e- + e+ The Attempt at a Solution Conservation of momentum: p1 - p2 = (0.5)pe...
  15. E

    Threshold frequency and wavelength of electrons in the photoelectric effect

    Homework Statement Electrons are emitted from a metal as a consequence of their absorption of energy from a light beam. Find the threshold frequency of the metal and the wavelength of emitted electrons. Wavelength of incident light λ = 500 nm Work function of the metal \phi = 2.1 eV Homework...
  16. A

    Inelastic Collision: Threshold Energy

    Homework Statement A thin target of lithium is bombarded by helium nuclei of energy E0. The lithium nuclei are initially at rest in the target but are essentially unbound. When a Helium nucleus enters a lithium nucleus, a nuclear reaction can occur in which the compound necleus splits apart...
  17. S

    Nuclear Photo Reaction + Threshold Energy

    Homework Statement I am given a scenario where a photon and a nuclei interact and create two daughter nuclei/particles. I won't bother with the full scenario as it would be nice to solve this generally, but we may assume we know the mass of all nuclei involved. The question is then what...
  18. O

    Threshold frequency of metals

    Is there fixed data for the threshold frequency of metals? For example, is it possible to find out the threshold frequency of iron or copper? OR does threshold frequency vary so greatly that with 2 blocks of iron, the theshold frequency could differ between them? Depending on the...
  19. B

    Finding Threshold Energy for Electrons to Produce Cerenkov Radiation

    Homework Statement Determine the threshold energy for electrons to produce Cerenkov radiation in glass (refractive index n=1.52). The Attempt at a Solution The only equations given in my notes are: cos \theta_{C}=1/\betan for \beta>1/n and...
  20. G

    Energy Threshold for 2 proton -> 2 proton 1 Pion

    Homework Statement When a beam if high-energy protons collides with protons at rest in the laboratory, pions are produced by the reaction p + p --> p + p + ∏. Compute the threshold energy of the protons in the beam for this reaction to occur. Homework Equations (mc^2)^2 = E^2 - (pc)^2...
  21. I

    Threshold temperature { Failure of delong petit law}

    Homework Statement Hi all, I have been trying to go over this problem for sometime now.. yes I have easily browsed over +200 articles, lectures , etc on google. The question is related to delong petit law and wants me to find out the temperature at which it fails i.e when quantum effects...
  22. J

    How to calculate threshold frequency of a metal

    Homework Statement Determine the threshold frequency of a metal with a work function of 7V Homework Equations Threshold frequency 'f'=W/h where w=work function, h=planck's constant The Attempt at a Solution This is such an easy question, but I am hung up on how to treat a work...
  23. L

    Photoelectric Effect ~ threshold frequency dependent on incident light?

    Homework Statement True/False: In the photoelectric effect, the cut-off (threshold) frequency depends on the intensity of incident light. Homework Equations hv = W + 1/2mv^2 v = W/h The Attempt at a Solution The threshold frequency depends on the wavelength of incident light...
  24. C

    Threshold speed in wind turbine. Is it dependent on frictional resistance?

    hey! Wind turbines have got certain threshold speed of wind (of about 6-7 m/s) which acts as a mechanical resistance to its rotation. Is this mechanical resistance a result of frictional resistance in bearings alone, or it is also a result of its own weight? If yes, approximately how much...
  25. C

    Calculating the threshold ionization intensity for hydrogen gas.

    Homework Statement Calculate the threshold ionization intensity for hydrogen gas. The attempt at a solution The way I tried to work it out was to use the field intensity of air which breaks down at, 3x10^6V/m. The ionization potential of oxygen is 13.618ev, 14.534ev for nitrogen and 13.598ev...
  26. K

    What Is the Threshold Energy for Lithium-Helium Nuclear Reactions?

    Homework Statement A thin target of lithium is bombarded by helium nuclei of energy E0. The lithium nuclei are initially at rest and are essentially unbound for this high-energy collision. A nuclear reaction can occur in which 4He + 7Li → 10B + 1n −2.8 MeV The collision is inelastic, and...
  27. M

    Single photon interference time threshold (double slit experiment)

    In the paper (AIP Conf. Proc. 810 (2006), 360): Mardari outlines three predictions of quantum self-interference, all of which empirical evidence is presented that appear to refute all three. The implications of the paper is interesting but of these I am particularly interested in the...
  28. A

    Help finding Maximum Depolarization of the membrane above threshold.

    Homework Statement We will deal here with a certain identified synapse in the CNS of the mooncalf (Bos lunaris). The post synaptic cell has voltage-sensitive channels like the squid axon-- a rapidly depolarizing, inactivating channel which conducts only sodium ions, and a slowly depolarizing...
  29. W

    What Would You See at the Threshold of the Expanding Universe?

    Say you were at the very edge of the universe and moving with it at the expansion rate and you look out to the "nothingness" what would you see? I personally think that the "Ganzfield Effect" would take place, when some of your perceptions are shut then your mind compensates. So I was...
  30. C

    Would an object appear frozen while crossing into the threshold

    Just as a note I am new to these forums and this is my first post after reading for a little while, I have no technical expertise and am a complete layman. So any advice on posting is welcome. From reading threads on these forums discussing properties of black holes and event horizons as I...
  31. D

    The Secrets of Nuclear Threshold Concepts: A Comprehensive Guide

    I want to know all about nuclear thresholds...where can i learn about them...? (e.g threshold energy and how particles behave under them...different types of threshold energy and their behavior)
  32. B

    Webpage title: How can I measure the threshold voltage for my muon experiment?

    Hi, Im currently doing an experiment with muons : detection, measuring lifetimes, mass etc. Im currently struggling with a basic measurement. I have a standard NIM crate setup, with discriminator, delay, coincidence units etc, and an oscilloscope. I have no user manuals for any of the units...
  33. D

    What are the different types of thresholds in particle collisions?

    I want to know about the thresholds of particles observed when colliding two matter particles together in fermilab or CERN i.e the pion production threshold is 290 MeV, what other thresholds are there? What is the complete list of thresholds according to the energy provided? "Is there a...
  34. ApexOfDE

    [Laser] Inversion number above and below threshold

    Homework Statement Consider a 3-level laser. Give the occupation numbers N1(R), N2(R), the inversion \DeltaN(R)/N = [N2(R) - N1(R)]/N and the flux below and above the threshold as a function of pump rate R. F - the photon flux Homework Equations The Attempt at a Solution I have...
  35. B

    Reduce relativistic KE threshold to a nonrelativistic form.

    Homework Statement Show that equation 14.13 reduces to equation 13.14 in the nonrelativistic limit. Homework Equations (14.13) K_{th} = -Q \frac{m_1 + m_2 + m_3 + ...}{2m_2} (13.14) K_{th} = -Q ( 1 + \frac{m(x)}{M(X)} ) The Attempt at a Solution For equation 13.14 m(x) is the...
  36. J

    What is the threshold energy for a neutrino reaction with a proton?

    Im a little confused about how to calculate threshold energies. The threshold energy is when the energy is as low as it can possibly be and still do what it has to do, yes? So when a neutrino is detected its speed is refracted by water and so it slows down. If at the threshold the neutrino speed...
  37. S

    Find Threshold Energy to Generate a Pion

    Homework Statement A high speed proton of rest mass M collides with a proton at rest in such a way that not only do the two protons emerge from the collision, but also a pion of mass m. Find the threshold kinetic energy of the incoming proton for such a pion to be generated. Show that the...
  38. K

    What is the threshold wavelength for this surface?

    Homework Statement A surface of a substance has a work function of 2.24 eV. (a) What is the maximum kinetic energy of ejected electrons if the incident radiation is of wavelength 419 nm? eV (b) What is the threshold wavelength for this surface? nm Homework Equations E=hf...
  39. M

    Adding a threshold in numerical codes

    Hi, I noticed such a strange behavior in my code every time I add a threshold: little oscillation around the threshold value itself. For example f(x) = g(x), x > x_c f(x) = 0, x <= x_c \frac{dx}{dt}=f(x) I solve the last equation and I find this oscillation. Can they be removed?
  40. S

    What is the threshold energy for gamma+e→3e and gamma→e⁺e⁻ reactions?

    Can someone help me out with this problem(not homework ofcourse).. Find the threshold energy of gamma quantum required to form - an electron-positron pair in the field of a stationary electron; - a pair of pions of opposite signs in the field of a stationary proton.. Thank you for reading
  41. S

    Is There a Safe Threshold for Ionizing Radiation?

    I've heard talk of this safety threshold for ionizing radiation, whereby if the dose is sufficiently low enough, it would produce no harmful side-effects. Can someone explain to me the reasoning behind this? The way I see it, every single ionizing particle that passes through a cell has a...
  42. R

    FREQUENCY: Radio to Infrared threshold

    Hi folks, EM radio signals range in frequencies from a couple Hz up to approximately EHF (30-300GHz)... As we exceed the 300GHz threshold, we begin to approach the infrared section of EM spectrum, and furthermore into the visible light area of the spectrum. My question is, what happens...
  43. S

    Diode clipping at a given threshold

    First post, after tinkering with electronics so long I just had to join a physics oriented forum. I'm trying to work out how I can get an input voltage to "clip" at a certain level. I start by imagining an ideal diode (no current on reverse bias, infinite current on forward bias). My setup...
  44. C

    Finding MOSFET threshold voltage

    Homework Statement I have a MOSFET with a Si/SiO_{2} interface. I need to find the threshold voltage. I'd also like to know whether this puts the transistor in the "on" state or "off" state (I know this is simple; I'd just like a little verification). I know the values for \Phi_{ms}, Q_{i}...
  45. E

    How is the threshold for Cerenkov counters calculated?

    Hi everyone, I have a problem with the following equation that is related to Cerenkov counter. You can find it at page 56 of "Introduction of High Energy Physics" by Perkins. The equation is the following: sin ^{2} (\theta _1)=1-\frac{1}{\beta...
  46. 0

    Pain Threshold - Reducing Intensity

    Homework Statement At a distance of 30 m the noise from the engine of an jet has an intensity of 130 dB. At this level, you will be in pain and your ears will hurt. That's why this intensity is know as the "pain threshold". How far do you have to be from a jet (total distance), in...
  47. T

    Calculate the kinematic threshold energy of a proton

    Homework Statement Given the reactions: p + 9 Be --> 10B + "gamma" p + 9 Be --> 9B + 1n p + 9 Be --> 9Be + 1p p + 9 Be --> 8Be + 2H p + 9 Be --> 7Be + 3H p + 9 Be --> 6Li + 4He Calculate: a) Q-value b) kinematic threshold energy of the proton...
  48. S

    Physical properties & threshold frequency

    What effects do the physical properties (size of atom etc.) of an elemental metal have on the threshold frequency for that metal? I haven't been able to find a correlation between a physical property and the size of the threshold frequency myself; maybe I haven't looked hard enough, or maybe...
  49. J

    Stack Effect in CMOS Design: Threshold Voltage Impact

    What is stack effect in cmos design and how would it affect the threshold voltages?
  50. M

    Photon energy threshold for γ+p→p+π, question *interpretation*

    Homework Statement Calculate the photon energy threshold for the reaction γ + p → p + π. Assume that the initial state proton is stationary. <thats really it> Homework Equations < unknown, but suspects include: standard special relativity equations > -- other useful relations: proton rest...
Back
Top