BSLEC 1 Flashcards
Set of mathematical procedures for organizing, summarizing, and interpreting information
Statistics
some of the most fundamental tools and techniques of the scientific method:
forming hypotheses.
designing experiments and observational studies,
gathering data,
summarizing data,
drawing inferences from data (e.g., testing hypotheses)
refers to a numerical quantity computed from sample data (e.g., the mean, the median, the maximum)
statistic
study and development of statistical theory and methods in the abstract
Mathematical Statistics
application of statistical methods to solve real problems involving randomly generated data, and the development of new statistical methodology motivated by real problems
Applied Statistics
branch of applied statistics directed toward applications in the health sciences and biology
Biostatistics
the set of all measurements of interest to a researcher.
Population
Populations can be thought of as ___
existing or conceptual.
well-defined sets of data containing elements that could be identified explicitly
Existing populations
are non-existing, yet visualized, or imaginable, sets of measurements.
Conceptual populations
Set of individuals selected from a population, usually intended to represent the population in a research study
Sample
A value, usually numerical value, that describes a population
Parameter
A value, usually a numerical value, that
describes a sample
Statistics
Usually derived from measurements of the individuals in the population
Parameter
A sample statistic is ____ of the average of the statistic is equal to the population parameter.
unbiased
A sample statistic is ___ if the average value of the statistic either underestimates or overestimates the corresponding population parameter.
biased
Two types of variables
Qualitative variables
Quantitative variables
can assume numeric values
Quantitative variables
Nonnumeric in nature
Qualitative variables
Quantitative variables
are classified into two groups:
discrete variables and continuous variable
Variable having only Integer values
Discrete variables
variable that is not restricted to particular values
Continuous variable
Observations (I.e., dependent variables) that occur in one of two possible states, often labelled zero and one.
Binary variable
Usually an independent or predictor variable that contains values indicating membership in one of several possible categories
Categorical Variable
A variable that obscures the effects of another variable.
Confounding variable
An extraneous variable that an investigator does not wish to examine in a study.
Control variable
The presumed effect in a nonexperimental study.
Criterion variable
The presumed effect in an experimental study.
Dependent variable
Created by recoding categorical variables that have more than two categories into a series of binary variables,
Dummy Variables
A variable that is an inherent part of the system being studied and that is determined from within the system.
Endogenous variable
A variable entering from and determined from outside of the system being studied
Exogenous variable
The presumed cause in an experimental study. All other variables that may impact the andent dependent variable are controlled.
Independent variable
A variable that explains a relation or provides a causal link between other variables.
Intervening variable .
lso called by some authors “mediating variable” or “Intermediary variable.”
Intervening variable .
An underlying variable that cannot be observed.
Latent variable
An observed variable assumed to indicate the presence of a latent variable.
Manifest variable
Also known as an Indicator variable.
Manifest variable
Synonym for intervening variable.
Mediating variable
A variable that influences, or moderates, the relation between two other variables and thus produces an interaction effect.
Moderating variable
A variable used to rank a sample of individuals with respect to some characteristics, but differences (.e., Intervals) and different points of the scale are not necessarily equivalent.
Ordinal variable
The presumed effect in a nonexperimental study. Synonym for criterion variable,
Outcome variable
Variables that can have more than two possible values, Strictly speaking, this includes all but binary variables.
Polychotomous variables
The presumed “cause” of a nonexperimental study. Often used in correlational studies.
Predictor variable
Measurements or observations
Data
A collection of measurements or observations
Data set
A single measurement or observation and is commonly called a score or raw score.
Datum
Firsthand data or raw data
PRIMARY DATA
which is already collected and recorded by any person other than the user for a purpose, not relating to the current research problem
Second-hand information
readily available form of data collected from various sources like censuses, government publications, internal records of the organization, reports, books, journal articles, websites, etc.
SECONDARY DATA
Two Types of Statistical Method
Descriptive statistics
Inferential statistics
Concerned with the describing the target population
Descriptive Statistics
Make inferences from the sample and generalize them to the population.
Inferential Statistics
Compares,tests and predicts future outcomes.
Inferential Statistics
Organize,analyze and present the data in a meaningful manner
Descriptive Statistics
Final results are shown in form of charts, tables and graph
Descriptive Statistics
Final result is the probability scores
Inferential Statistics
