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EBC 2 Midterm > Biostatistics Basics > Flashcards

Flashcards in Biostatistics Basics Deck (31)
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1

What are the 2 types of variables?

Independent
Dependent

2

Independent variables precede dependent variables in what?

Time

3

What variable can be manipulated by the researcher?

Independent

4

The treatment or intervention is what variable?

Independent

5

The dependent variable depends on what?

Independent Variable

6

What is the group from which a sample is drawn?

Population

7

What is a subset of a population?

Sample

8

What type of samples are representative of the source population?

Random Samples

9

Random assignment is also known as?

Randomization

10

What is a way to summarize data from a sample or a population?

Descriptive Statistics

11

Descriptive statistics illustrate what of a set of data?

Shape
Central Tendency
Variability

12

The shape of the data involves frequencies of what?

Values of observataions

13

Central tendency means the location is where?

Middle of the data

14

Variability refers to?

Spread
Dispersion

15

What visually depict frequency distributions of continuous data?

Histograms

16

What are used to depict categorical information?

Bar Charts

17

What is the most common descriptive statistic?

Mean (average)

18

What is the most frequently occurring value in a series?

Mode

19

The value that divides a series of values in half when they are all listed in order is known as what?

Median

20

What are the 4 levels of measurement?

N-Nominal (name/label)
O-Ordinal (ordered rank)
I-Interval (equal intervals)
R-Ratio (true zero)

21

What are often symmetrical with most scores falling in the middle and fewer toward extremes?

Distributions

22

Most biological data are symmetrically distributed and form what?

Normal Curve (bell-shaped curve)

23

The area under a normal curve has what?

Normal Distribution

24

What are some properties of a normal distribution?

Symmetric about it's mean
Highest point is at mean
Height of curve decreases as one moves away from mean in either direction, never reaches zero.

25

What does it mean when there is a skewed distribution?

Mean, median and mode are not equal and are in different positions.

26

Skew is always toward the direction of which tail?

Longer Tail
+ = Right
- = Left

27

What is a better estimate of the center of skewed distributions?

Median (central point of distribution)

28

What is a measure of the variability of a set of data?

Standard Deviation

29

The range of scores is referred to as?

Variability or Spread

30

What is the number of standard deviations that a specific score is above or below the mean in a distribution?

Z-Scores