Data & Interpretation

Question 1

Statistics

Answer 1

The science whereby inferences are made about specific phenomena on the basis of relatively limited sample material

Question 2

What are two main areas of statistics and define.

Answer 2

1. mathematical statistics - the development of new methods of statistical inference and requires detailed knowledge of abstract mathematics for its implementation
2. applied statistics- involves applying the methods of mathematical statistics specific subject areas, such as economics, psychology, and public health

Question 3

Biostatistics

Answer 3

The branch of applied statistics that applies statistical methods to medical and biological problems.

Question 4

Frequency Distribution

Answer 4

Lists each value in the data and how frequently it occurs

Question 5

Continuous Distribution

Answer 5

Infinite number of possible values

Question 6

Discrete Distribution

Answer 6

Only a few possible values

Question 7

Inferential Statistics

Answer 7

Used to determine if differences in outcome variables in your data are real or simply due to chance

Question 8

Error of the estimate

Answer 8

The difference between your sample data estimate and the true population measure for the variable in question

Question 9

Measure of Location

Answer 9

Summarizes data by defining the center, or middle, of the sample

Question 10

Mean (average)

Answer 10

The sum of all observations divided by the number of observations

Question 11

Median

Answer 11

The middle score

Question 12

Mode

Answer 12

The most frequently occurring value among all of the observations in a sample

Question 13

Variability of a sample

Answer 13

The spread of the data

Question 14

List four examples of measures of spread

Answer 14

1. Range
2. Quantiles
3. Variance
4. Standard Deviation

Question 15

Range

Answer 15

The difference between the largest and smallest observation in a sample.

Question 16

How to calculate percentile

Answer 16

1) The (k +1)th largest sample point if np/100 is not an integer (where k is the largest integer less than np/100).
2) The average of the (np/100)th and (np/100 =1)th largest observations if n*p/100 is an integer.

Question 17

Mean deviation

Answer 17

The difference between an individual sample and the mean

Question 18

Variance

Answer 18

The variance(known as 𝑠2) is the sum of the differences of each data point from the mean, squared and divided by N-1

Question 19

Standard Deviation

Answer 19

The measure of the spread of scores within a set of data. The square root of the variance

Question 20

Coefficient of variation (CV)

Answer 20

Relates the mean and standard deviation to each other. Useful for comparing the variability of several different samples, each with different means.

Question 21

Frequency Distribution

Answer 21

An ordered display of each value in a data set together with its frequency

Question 22

Probability

Answer 22

The relative frequency of this set of outcomes over an indefinitely large (or infinite) number of trials

Question 23

Sample Space

Answer 23

Set of all possible outcomes

Question 24

Event

Answer 24

Any set of outcomes of interest

Question 25

What are the two basic properties of probabilities

Answer 25

1. The probability of an event E, denoted by Pr(E), always satisfies 0 le PR(E) le 1.
2. If outcomes A and B are two events that cannot both happen at the same time, the PR (A or B occurs) = PR(A) + PR(B).

Question 26

Mutually Exclusive

Answer 26

Events cannot both happen at the same time

Question 27

The multiplication law of probability

Answer 27

If two events are independent, then

Pr(A∩B) = Pr(A) x Pr(B)