Scatter Diagrams and Correlation

Scatter Diagrams and Correlation

Friction

• Friction is a force that opposes motion between two surfaces that are in contact with each other
• Static friction occurs when objects remain static whereas kinetic friction comes into play when objects are moving.
• Friction depends on the nature of the surfaces and the force pressing them together.

Normal Friction

• Normal force acts perpendicular to the surfaces in contact and increases with the weight of the object and surface area.
• The direction of the frictional force is always opposite to the potential movement direction of the object.

Limiting Friction

• Limiting friction is the maximum static friction that needs to be overcome to initiate motion.
• Once a body is in motion, the friction acting on it is called kinetic or dynamic friction that is slightly less than the limiting friction.

Moments

• Moments are the turning effect of a force and are calculated by multiplying the force by the distance from the pivot point.
• The principle of moments states that for a body to be in equilibrium, the sum of anticlockwise moments about a point must equal the sum of clockwise moments about the same point.

Statistics

• Statistics involves collecting, organizing, analyzing, and interpreting numerical information to make conclusions or predictions.

Limits and Boundaries

• In statistics, limits and boundaries refer to the upper and lower values in a class.

Class-widths and Mid-ages

• Class-width is the difference between the upper and lower class limits.
• Mid-ages are the midpoint of a class in a grouped frequency table and are used for calculations.

Age Distribution

• Age distribution represents the age structure of a population, usually displayed in a histogram.

Histograms

• A histogram is a graphical representation that organizes a group of data points into a specified range.

Measures of Central Tendency and Dispersion

• Measures of central tendency include the mean, median, and mode, which represent a central value in a dataset.
• Measures of dispersion, such as the range, variance, and standard deviation, describe how spread out the values in the dataset are.

Standard Deviation, Mean and Median

• The standard deviation measures the average distance between each data point and the mean.
• The mean is the average value in a dataset.
• The median represents the middle value in a dataset when the data are ordered from smallest to largest.

Probability

• Probability expresses the likelihood that a specific event will occur, calculated by the number of desired events divided by the total number of outcomes.

Venn Diagrams

• A Venn diagram uses overlapping circles to visually display the relationships between different sets of data.

Tree Diagrams

• A tree diagram is a graphical representation of all the possible outcomes of an event and is used to calculate the probability of complex events.

Conditional Probability

• Conditional probability is the likelihood of an event occurring, given that another event has already occurred.

Bivariate Analysis

• Bivariate analysis involves the comparison of two variables to determine the relationship between them.

Scatter Diagrams and Correlation

• A scatter diagram is a graph in which the values of two variables are plotted along two axes.
• Correlation measures the strength and direction of the relationship between two variables.