Exam 3 - Biostatistical Tests Flashcards Preview

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Flashcards in Exam 3 - Biostatistical Tests Deck (79)
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1

A research perspective which states there will be no true difference between the groups being compared.

Null hypothesis

2

Three attributes that differ between nominal/ordinal/interval/ratio data.

Order/magnitude, spacing/scale, rational absolute zero

3

Does nominal data have magnitude? Does nominal data have a consistent scale?

No; No

4

Does ordinal data have magnitude? Does ordinal data have a consistent scale?

Yes (i.e. it can be ordered); No (example = satisfaction survey)

5

Does interval/ratio data have magnitude? Does interval/ratio data have a consistent scale?

Yes; Yes (Tigger/Buzz = Units)

6

Black

Nominal

7

Red

Ordinal

8

Orange

Interval

9

Yellow

Ratio

10

True/False: After data collection you can move up (i.e. nominal => ordinal => interval => ratio) is specificty.

False, you may only move down

11

Average of the squared-differences in each individual measure value (x) and the groups' mean.

Variance

12

Square root of variance value

Standard deviation

13

In a normal distribution curve the first standard deviation represents how much of the data?

68%

14

In a normal distribution curve the second standard deviation represents how much of the data?

95%

15

In a normal distribution curve the third standard deviation represents how much of the data?

99.7%

16

Statistical test useful for normally-distributed data.

Parametric (i.e. associated with interval/ratio data)

17

Data distribution, asymmetrical, mean > median, tail points right

Positively skewed

18

Data distribution, asymmetrical, mean < median, tail points left

Negatively skewed

19

Skewness value of 0.

Symmetrical data distribution (i.e. not skewed)

20

Positive skewness value.

Positively skewed

21

Negative skewness value.

Negatively skewed

22

Numerical value that evaluates how aggregated a data set may be (i.e. how clusted the data is)

Kurtosis (i.e. + = more cluster)

23

Four key questions for selecting the correct statistical test.

  1. What data level is being recorded? (i.e. nominal, ordinal, interval/ratio)
  2. What type of comparison/assessment is desired?
  3. How many groups are being compared?
  4. Is the data independent or related/paired?

24

Buzz words for correlation statisical test.

Correlation, association, relationship

25

Buzz words for regression statistical test.

Prediction, association, relationship.

26

Statisical test that derives a quantitative measure of strength and direction between the relationship of two variables.

Correlation

27

Nominal correlation test.

Contingency Coefficent

28

Ordinal correlation test.

Spearman Correlation

29

Interval/ratio correlation test.

Pearson correlation

30

A correlaiton that controls for confounding variables (i.e. only for interval data)

Partial correlation