Statistics conceptual map

Statistics conceptual map

1. is the science of collecting, describe,analyze, and interpret data.

   • The study of statistics can be divided in two main areas.
     • Descriptive statistics has to do with the collection, organization,overview and presentation of data.
     • Inferential statistics, has to do with obtaining inferences or conclusions about the populations based on samples
   • Population: is the totality of the elements under consideration
   • Sample: is the portion of the population that is selected
   • Parameter: is a measure of overview

2. Random Variables

   • Qualitative Variables
   • Quantitative Variables
     • Continuous
     • Discrete

3. Property of Measurements Scales

   • Identity: has Unique meaning
   • Magnitude: have an ordered relationship to one another
   • Equal Intervals: Equal to one another
   • Minimum value of zero: The scale has true zero point
   • Nominal scale of Measurements: Identity
   • Ordinal Scale of Measurements: Identity and Magnitude
   • Interval Scale of Measurements: Identity, Magnitude and equal intervals
   • Ratio Scale of Measurements: All four properties

4. Sampling Methods

   • Population Parameter vs. Sample Statistic
     • Population parameter: is the true value of a population attribute.
     • Sample statistic: an estimate, based on sample data, of a population parameter.
   • Probability vs. Non-Probability Samples
     • Probability samples: each population element has a known (non-zero) chance of being chosen for the sample.
     • Non-probability samples:, we do not know the probability that each population element will be chosen, and/or we cannot be sure that each population element has a non-zero chance of being chosen.
   • Non-Probability Sampling Methods
     • Voluntary sample. A voluntary sample is made up of people who self-select into the survey.
     • Convenience sample. A convenience sample is made up of people who are easy to reach.
   • Probability Sampling Methods
     • Simple random sampling
     • Stratified sampling
     • Cluster sampling
     • Multistage sampling
     • Systematic random sampling

5. Visual Displays of Datas

   • Graphs

6. Measure of Central Tendency

   • Median
     • Average
   • Median
     • Middle number of ordered group of numbers
   • Mode
     • The most repeated number

7. Measure of Dispersions

   • Standard Deviation
     • sqrt(E(x-average x)/n-1)
   • Range
     • Largest value- Smallest Value
   • Coefficient of Variation
     • VQ= (s/average x) *100%
   • Chevyshev's Theorem
     • 1-(1/k^2)

8. Measure of position

   • Percentile= 1 by 1
   • Decile= 10 by 10
   • Quartile= 25 by 25
   • P50=D5=Q2
     • Median