lecture 4 - regression Flashcards

1
Q

what do regression tests look at?

A

whether x influences y

an effect

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2
Q

what are the 3 different terms for x?

A
  • independent
  • explanatory
  • predictor
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3
Q

what are the 3 different terms for y?

A
  • dependent
  • outcome
  • criterion
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4
Q

which axis is the x variable always on?

A

horizontal

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5
Q

which axis is the y variable always on?

A

vertical

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6
Q

what is the simplified regression equation?

A

y = a+bx

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7
Q

a =

A

intercept (where the line on the graph starts)

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8
Q

b =

A

the slope
this is the coefficient
tells us how much y changes by with one unit change in x

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9
Q

the larger the value of b…

A

the steeper the line

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10
Q

if b = 0 the line is…?

A

flat

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11
Q

y = a+bx is the equation for?

A

a straight line

simplified regression equation

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12
Q

OLS regression

A
  • works out error

- shows the best place for the line of best fit according to the least amount of error

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13
Q

what does OLS stand for?

A

ordinary least amount of squares

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14
Q

what is error also referred to as?

A

residual

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15
Q

what are the 2 most important elements to consider when assessing b?

A
  1. direction and size

2. statistical significance

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16
Q

what is the extended equation with OLS regression?

A

y = a + bx + u

17
Q

what does u stand for in the extended regression equation?

A

error

18
Q

what is the value of R squared always between?

A

1 and 0

  • 1 is the perfect model and explains the data exactly
  • 0 is doing nothing to explain the data
19
Q

is R squared a proportion?

A

yes - e.g. if it = 0.4, this means it explains 40% of the variance in Y with our X