LEC 1 Flashcards
Fields of Statistics
Descriptive statistics
Inferential statistics
__________ is concerned with the methods of collecting, organizing, and presenting data appropriately and creatively to describe or assess group characteristics.
Descriptive statistics
_________ is concerned with inferring or drawing conclusions about the population based from pre-selected elements of that population.
Inferential statistics
A __________ is a characteristics that changes or varies over time and/or for different individuals or objects under consideration.
Variable
_____________ measure a quality or characteristics on each individual or object.
Qualitative variables
____________ measure a numerical quality or amount on each individual or object, often represented by x.
Quantitative variables
A _________ can assume only a finite or countable number of values.
Discrete variable
A __________ can assume the infinitely many values corresponding to the point on a line interval.
Continuous variable
Classification of Variables
- According to functional relationship
- According to scale of measurements
Classification of Variables
According to functional relationship
- Independent variable
- Dependent variable
Classification of Variables
According to scale of measurements
- Nominal variable.
- Ordinal variable
- Interval variable
- Ratio variable
This is sometimes termed as predictor variable.
Independent variable
This is sometimes called criterion variable.
Dependent variable
For example, academic achievement is dependent on IQ.
IQ is the _______ variable and academic achievement is the ______ variable.
independent, dependent
This property allows one to make statements of similarities or differences.
Nominal variable
This variable refers to a property whereby members of a group are ranked.
Ordinal variable
This property allows one to make statements of equality of intervals.
Interval variable
This property permits making statements of equality of ratios.
Ratio variable
There are two sources of obtaining data.
- Primary Sources
- Secondary Sources
_________ is the firsthand information is obtained usually by means of personal interview and actual observation.
Primary source
The _______ source of information is taken from other’s works, news reports, reading, and those that are kept by the National Statistics Office, Securities and Exchange Commission, SSS, and other government and private agencies.
Secondary source
Methods of Collecting Data
- Direct or Interview Method
- Indirect or Questionnaire Method
- Registration Method
- Observation Method
- Experimentation
Data that are collected by these methods are usually referred to as ________.
raw data
______ are not yet organized and presented in a form ready for interpretation. These data can only be understood if appropriate forms of presentation are adopted.
Raw data
PPSS
Population has a parameter while sample is for statistics.
A ________ is a finite or limited collection of objects, events, or individuals selected from a population.
sample
_________ is a finite or infinite collection of objects, events, or individuals with specified class or characteristics under consideration, such as students in a certain university, legitimate taxi drivers in Metro Manila, cellular phone users, etc.
Population
A capital letter “N” is used to denote _____ size whereas small letter “n” denotes _________ size.
N = population size
n = sample size
The Greek letters (read as ____), 𝜎 (____), 𝜎2(_____), and ⍴ (___)
The greek letters (read as miu), 𝜎 (sigma), 𝜎2 (sigma squared), and ⍴ (rho)
Symbols for Parameter
- Population size = ______
- Population mean = ______
- Population standard deviation = ______
- Population variance = ______
- Population coefficient of correlation = ______
Symbols for Parameter
- Population size = N
- Population mean = μ
- Population standard deviation = 𝜎
- Population variance = σ2
- Population coefficient of correlation = ρ
Symbols for Statistic
- Sample size = ______
- Sample mean = ______
- Sample standard deviation = ______
- Sample variance = ______
- Sample coefficient of correlation = ______
Symbols for Statistic
- Sample size = n
- Sample mean = X̄
- Sample standard deviation = s
- Sample variance = s2
- Sample coefficient of correlation = r
Sloven’s Formula
N
———– = n
1+Ne2
N
———– = n
1+Ne2
Let N be the _____ size and the ______of error e denotes the allowed probability of committing an error in selecting a small representative of the population.
The ______ size n can be obtained by the formula
Let N be the population size and
the margin of error e denotes the allowed probability of committing an error in selecting a small representative of the population.
The sample size n can be obtained by the formula
Law of ____ Numbers states, “ the larger the size of the sample, the ____ certain we can be sure that the sample mean is a good _____ of the population mean.”
more certain
–
estimate
This margin of error, e, could range between ___ and ___ depending on the desire or intention of the researcher.
0.01 and 0.1
A _____ is a portion or sub-aggregate of the population that should represent the common qualities or characteristics of the population.
Sample
