Math for Life Sciences Exam 2 Vocabulary

Statistics

the study of how to collect, organize, analyze, and interpret data collected from a group

Descriptive statistics

the branch of statistics where you collect and organize data

Inferential statistics

Individual 

a person or object that you are interested in finding out information about

Variable

the measurement or observation of the individua

Population

set of all values of the variable for the entire group of individuals

Sample

a subset from the population looks just like the population, but contains less data

Parameter

a number calculated from the population; this number is a fixed, unknown value you want to find

Statistic

a number calculated from the sample; it is readily known and used to estimate the parameter value 

Qualitative/ categorical variable

variable that describes the quality of the individual (word or name)

Quantitative variable

variable that describes something that can be sounted or measured from the individual 

Discrete data

data that can only take on a particular value; usually things you count

Continuous data

data that can take on any value; usually things you measure

Nominal data

data that is just a name or category'; no order or calculations (ex. gender, race); come from qualitative variables

Ordinal data

data that is nominal but can be put in order and no calculations (ex. letter grade, drink size); come from qualitative variables

Interval data

data that is ordinal but can also be subtracted (ex. temp., time); come from quantitative variables

Ratio data

data that is interval but can also be divided (ex. weight, height); come from quantitative variables

Simple random sample

a sample selected from a population where each individual has an equal chance of being selected

Stratified sampling

sampling method where you break the population into groups and then take a simple random sample from each group

Systematic sampling

sampling method where you choose a random starting place then select every nth individual to measure

Cluster sampling

sampling method where you break the population into groups and randomly select some groups, polling all individuals in the groups

Convenience sample

sampling method where individuals are selected because of ease to collect

Census

sampling method where every individual of interest is measured

Observational study

study where an investigator collects data by watching or asking questions

Experimental study

study where an investigator changes a variable or imposes a treatment to determine an effect

Survey

data collection that uses questions to collect data, used in observational studies