math haha Flashcards
Patterns in Nature
Symmetry
Trees, Fractals
Spirals
Waves, dunes
Bubbles, foam
Tessellations
Cracks
Spots, stripes
GOLDEN RATIO
1.618
Two Branches of Statistics
Descriptive Statistics
Inferential Statistics
Using the data gathered on a group to describe or reach conclusions about the same group
E.g., class average, range of scores in an exam
Descriptive Statistics
A researcher gathers data from a sample and uses the statistics generated to reach conclusions about the population from the sample drawn.
Inferential Statistics
Two Types of Variables
Qualitative Variables (category)
Quantitative Variables (numbers)
Variables that can be placed into distinct categories according to some characteristic or attribute (e.g., gender)
Qualitative Variables (category)
Variables are numerical and can be ordered and ranked
Quantitative Variables (numbers)
Characteristic of interest about an object under investigation
Variable
Quantitative Variables
Discrete (whole number)
Continuous (decimal)
Countable. Data are obtained by counting
Example: the number of children in a family
Discrete (whole number)
Can assume an infinite number of values in an interval between any two specific values.
Examples: temperature
Continuous (decimal)
Four Levels of Data Management
- Nominal (naming, labeling, classification)
- Ordinal (ranking, order)
- Interval (zero has meaning)
- Ratio (zero has no meaning)
naming, labeling, classification
Nominal
– lowest level of data management
– for identification and classification
Nominal
ranking, order
Ordinal
use to reflect some rank or order of individuals or objects
Ordinal
where zero has meaning
Interval
zero is arbitrary (e.g., Temperature)
Interval
where zero has NO meaning
Ratio
– highest level of data measurement
– zero is absolute (e.g., height)
Ratio
Data Collection Method
- Survey (easy to conduct)
- Direct Observation (Qualitative)
- Experiment method (Cause and Effect)
- Registration Method (need to participate)
Makes use of questionnaires (can be telephone, email, personal)
Survey (easy to conduct)
Data regarding the behavior, attitudes, values, or cultural patterns of individuals are gathered.
Direct Observation (Qualitative)
The objective is to determine cause-and-effect relationships.
Experiment method (Cause and Effect)
Provide information to comply with a law or policy.
Registration Method (need to participate)
Different Forms of Presentation of Data
Textual
Tabular
Graphical Presentation
presents data in a paragraph form
Textual
-presents data in tables
-more precise, systematic, and orderly
Tabular
Effective method of presenting statistical results and can present clear pictures of the data
Graphical Presentation
Under Graphical Presentation
Bar Graph
Line Graph
Pie Chart
Pictogram (Picture Graph)
Cartogram (Map Graph)
consists of bars either vertically or horizontally and usually constructed for comparative purposes
Bar Graph
Shows the relationship between one or more sets of quantities; best used to establish trends
Line Graph
used to represent quantities that make up a whole.
Pie Chart
It utilizes picture symbols to represent values.
Pictogram (Picture Graph)
It is used to present geographical data.
A map is drawn and divided into the desired regions.
Cartogram (Map Graph)
Is a single score or value that stands for or represents a group of scores or values of the items in a set of data.
MEASURES OF CENTRAL TENDENCY
The sum divided by the count
MEAN (X̄)
This is a positional measure and the middlemost value in the distribution.
MEDIAN (Md)
This is the value or item in a distribution that occurs most frequently or has the highest frequency.
MODE (Mo)
- These are the scores of the students in a 20-item quiz: 13, 15, 18, 12, 11, 17, 18, 19, 20.
- 15.89
- These are the prices of sweet corn sold in San Pedro: 20, 23, 22, 18, 15, 25, 20, 30.
- 21.625
- Describes how spread the individual values are from the average
- values are used to determine the scatter of values in a distribution
Measures of Variability
Is the simplest and the easiest to compute among the measures of variability
Range
is the difference between the highest and the lowest score in the distribution.
R = H – L
is the square of the deviation from the mean
Variance
is the square root of variance.
Standard Deviation
- It is a measure of how far a set of numbers is spread out.
- It describes how far the numbers lie from the mean.
- A high standard deviation indicates that the data points are spread out over a large range of values
Standard Deviation
