Ch 1 Introduction to Biostatistics

Question 1

data

Answer 1

numbers resulting from counting or measurement

Question 2

datum

Answer 2

individual number

Question 3

statistics

Answer 3

field of study concerned with the collection, organization, summarization and analysis of data and the drawing of inferences about a body of data whe only part of the data is observed

Question 4

descriptive statistics

Answer 4

the collection, organization, summarization and analysis of data

Question 5

inferential statistics

Answer 5

the drawing of inferences about a body of data whe only part of the data is observed

Question 6

sources of data

Answer 6

routinely kept records, surveys, experiments, external resources

Question 7

biostatistics

Answer 7

the application of statistical tools and concepts to data derived from the biological sciences or medicine

Question 8

variable

Answer 8

a characteristic that takes on different values in different persons,
places, or things.

Question 9

quantitative variable

Answer 9

one measured in the usual sense and conveys information regarding amount

Question 10

qualitative or categorical variable

Answer 10

measuring consists of categorizing and the measurements convey information regarding attribute.

Question 11

frequencies or counts

Answer 11

the numbers we manipulate when our analysis involves qualitative variables

Question 12

random variables

Answer 12

values arise as a result of chance factors, and cannot be predicted in advance

Question 13

discrete random variable

Answer 13

characterized by gaps or interruptions in the values it can assume; you can count out possible values

Question 14

continuous random variable

Answer 14

can assume any value within a specified relevant interval values assumed by the variable

Question 15

population

Answer 15

the largest collection of entities for which we have an interest at a particular time. A population of values is the largest collection of values of a random variable for which we have an interest at a particular time. Populations may be finite or infinite

Question 16

sample

Answer 16

part of a population

Question 17

measurement

Answer 17

assignment of numbers to objects or events according to a set of rules

Question 18

nominal scale

Answer 18

classifying into mutually exclusive and exhaustive categories

Question 19

examples of nominal scale

Answer 19

medical diagnoses, and age groups

Question 20

ordinal scale

Answer 20

ranking among categories, where the distance between categories doesn’t have to be equal

Question 21

examples of ordinal scale

Answer 21

below average, above average, pain scale

Question 22

interval scale

Answer 22

has a unit distance and a zero point, so there is equality of intervals, this is a truly quantitative scale

Question 23

example of interval scale

Answer 23

temperature for F and C we have arbitrary 0’s. The distance from 30 degrees to 40 degrees represents the same heat gain from 70 degrees to 80 degrees but 20 degrees isn’t twice as hot as 10 degrees

Question 24

ratio scale

Answer 24

equality of intervals and ratios may be determined, there’s a true 0 point

Question 25

examples of ratio scale

Answer 25

height, weight, annual income, doubling weight will take 50lbs to 100lbs

Question 26

presenting data

Answer 26

identify the source and the individuals, how many are in the set, identify variable and type, identify units of measurement, label everything

Question 27

statistical inference

Answer 27

the procedure by which we reach a conclusion about a population on the basis of the information contained in a sample that ahs been drawn from that population

Question 28

simple random sampling (SRS)

Answer 28

a sample of the size n from a population of size N in such a way tht every possible sample of size n has the same chance of being selected

Question 29

research study

Answer 29

a scientific stduy of a phenomenon of interest, involves designing sampling protocols, collecting and analyzing data, and providing valid conclusions based on the results of the analysis

Question 30

experiments

Answer 30

a special type of research study in which observations are made after specific manipulatios of conditions have been carried out; they provide the foundation for scientific research

Question 31

systematic sampling

Answer 31

often used with a set of files of medical records. with the files numbered and ordered, a random startinbg point x is chosen along with an interval k. then the records are x, x+k, x+2k, etc

Question 32

stratified random sampling

Answer 32

a population of interest is partioned into groups, or strata in which the sample units within a particular stratum are more similiar to each other than they are to the sample units that compose other strata. then an SRS is taken from each stratum

Question 33

scientific method

Answer 33

process by which scienific information is collected, analyzed and reported in order to produce unbiased and replicable results in an effort to produce an accurate representation of observable phenomenon

Question 34

making an observation

Answer 34

leads to the formulation of questions or uncertainties that can be answered in a scientifically rigorous way

Question 35

formulating a hypothesis

Answer 35

to explain the observation and to make quantitative predictions of new observations. hypothese may be stated as either research hypotheses or statistical hypotheses

Question 36

designing an experiment

Answer 36

that wil yield the data necessary to validly test an appropraite statistical hypothesis

Question 37

accuracy

Answer 37

correctness of a measurement (validity)

Question 38

precision

Answer 38

consistency of a measurement (reliability)

Question 39

conclusion

Answer 39

based on the degree of confidence about the hypotheses that were posed as part of the design. but results need to be replicated, often a large number of times, before scientific credence is granted them