What is Significance: Definition and 278 Discussions

In statistical hypothesis testing, a result has statistical significance when it is very unlikely to have occurred given the null hypothesis. More precisely, a study's defined significance level, denoted by


{\displaystyle \alpha }
, is the probability of the study rejecting the null hypothesis, given that the null hypothesis was assumed to be true; and the p-value of a result,


{\displaystyle p}
, is the probability of obtaining a result at least as extreme, given that the null hypothesis is true. The result is statistically significant, by the standards of the study, when



{\displaystyle p\leq \alpha }
. The significance level for a study is chosen before data collection, and is typically set to 5% or much lower—depending on the field of study.In any experiment or observation that involves drawing a sample from a population, there is always the possibility that an observed effect would have occurred due to sampling error alone. But if the p-value of an observed effect is less than (or equal to) the significance level, an investigator may conclude that the effect reflects the characteristics of the whole population, thereby rejecting the null hypothesis.This technique for testing the statistical significance of results was developed in the early 20th century. The term significance does not imply importance here, and the term statistical significance is not the same as research, theoretical, or practical significance. For example, the term clinical significance refers to the practical importance of a treatment effect.

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  1. L

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    Can anyone explain the meaning behind a mobius strip? Basically just a means to travel on both sides of a flat surface? It's still a 3D object though since it uses 3D space for the twist to be possible?
  2. James1238765

    I What is the significance of the T - V Lagrangian of a system?

    Let E be a fixed immutable quantity. E can be freely exchanged between T and V, as long as $$T + V = E$$ 1. What does the quantity $$\int_x T - V $$ signify? What is the importance of this quantity? -------------------- Let E now be the budget of a factory. E can either be spent on T or V in...
  3. D

    A What is the significance of the Poincaré conjecture?

    Namely, what does Perelman’s proof of it imply?
  4. A

    A Significance of CMB anomalies?

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  5. L

    I Significance of double slit experiment?

    What is the significance of the double slit experiment? When I first learned about it I thought the human observer decided the outcome. But I guess a human observer isn't even needed and therefore a conscious mind is just as irrelevant. What does it prove that an outcome is neither one thing or...
  6. F

    I Significance of (1+1/x)^x as x->-inf

    Any practical or scientific significance of (1+1/x)^x as x->-inf?
  7. G

    Superdeterminism ruined the significance of DCQE experiment

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  8. patric44

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  9. R

    I Is there any physical significance to Wave Amplitude?

    I am studying Quantum physics and I'm having some problems to understand what is the Wave Amplitude since I can't find a physical significance to it. Does anyone ever heard something that come close to a physical significance?
  10. mfb

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  11. Hamiltonian

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  12. P

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  13. Hamiltonian

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  14. entropy1

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  15. Grinkle

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  16. S

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  17. T

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  18. sophiatev

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  19. M

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  20. cnh1995

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  21. Nathan Warford

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  22. S

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  23. C

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  24. Prof Sabi

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  25. P

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  26. I

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  27. dRic2

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  28. A

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  29. Muhammad Usman

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  30. Kostik

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  31. rishi kesh

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  32. R

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  33. S

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  34. Wrichik Basu

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  35. T

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  36. V

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  37. M

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  38. K

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  39. Mind----Blown

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  40. N

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  41. N

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  42. S

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  43. T

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  44. K

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  45. L

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  46. F

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  47. F

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  48. S

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  49. S

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  50. V

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