chp 4 Flashcards

1
Q

in most cases, the null hypothesis is something researchers hope to prove ____

A

false

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2
Q

results found as extreme as they are is measured by

A

p value

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3
Q

expecting that true groups in an experiment are identical is known as

A

null hypothesis

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4
Q

the p value proves the null hypothesis that results are due to ____ alone

A

chance

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5
Q

why do we want less than 0.05 value?

A

arbitrary; bc we want to REJECT null hypothesis

- say there IS a difference and not by chance

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6
Q

how is statistically significance measured

A

p value - shows there is a difference

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7
Q

define null hypothesis

A

no difference among groups and that observed differences are due to random variation (chance)

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8
Q

the smaller the p value the ___ the evidence is to dispute the null hypothesis

A

stronger

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9
Q

numeric representation of the degree to which random variation alone could account for the differences observed between groups

A

p value

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10
Q

when the null hypothesis is rejected, the result is said to be _____

A

statistically significant

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11
Q

when the p value is greater than 0.05, the null hypothesis can be ____

A

accepted

– saying it did happen by chance

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12
Q

the incorrect rejection of the true null hypothesis

A

type 1

  • false positive
  • saying there is a difference but actually not one
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13
Q

incorrectly retaining a false null hypothesis

A

type 2
false negative
-saying there is no difference when there IS one

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14
Q

t/f p values convey info regarding size

A

false

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15
Q

what is the CI if there is a large sample

A

narrow confidence interval

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16
Q

in a small sample the SEM is ___ and the CI is ____

A

larger; wider

17
Q

a test is called ____ tailed if the null hypothesis is rejected for values of the test statistic falling into either tail of its sampling distribution

A

two tailed

18
Q

test is ___ tailed if the null hypothesis is rejected only for the values of the test statistic falling into one specified tail

19
Q

which tail test is easier to achieve significance, why?

A

one tail

  • bc in two tail you have more possibility (less confident) it will fall in either side..
  • -> p value is HALF the two- tailed P value
20
Q

which tail test will you find a type 2 error

A

two tail

- more difficult to achieve significance

21
Q

in a one tail test, if results went other direction than predicted this means it ___ significant

A

not statistical significant

22
Q

which tail test should you have a prediction for direction

A

one tail test

23
Q

one tail has a chance for type ___ error

24
Q

which tail test is more often used?

A

two tail test

25
are two tailed test more or less conservative
more (have to divide them into two so 0.25 each side)
26
what is the threshold denoted by
alpha