Basic terms and definitions - Statistics and probability

It is the collection of methods for planning experiments, obtaining data, and then analysing, interpreting and drawing conclusions based on the data.

It is defined as a science that studies data to be able to make a decision. Hence, it is a tool in decision-making process.

Trivia: The word ''___'' actually comes from the word '''' - because governments have been involved in the statistical activities, especially the conduct of censuses either for military or taxation purposes. The need for and conduct of census are recorded in the pages of the holy texts. In the Christian bible, particularly the Book of Numbers, God is reported to have instructed Moses to carry out a a census. Another census mentioned in the Bible is the census ordered by Caesar Augustus throughout the entire Roman empire before the birth of Christ.

Statistics enable us to:

Are the values that the variables can assume.

Is a characteristic that is observable or measurable in every unit of the universe

Is a set of all possible values of a variable.

Is a subgroup of a population

Classification of variable, It is Words or codes that represent a class or category, Express a categorical attribute - Gender, Religion. and Marital status.

Classification of variable - Number that represent an amount, Numerical data, sizes are meaningful and answer question such as ''how many'' or ''how much'' - Height, Weight, Household size, Number of registered ears.

Quantitative Variables can be classified as - Data that can be counted - number of days, number of siblings, usual number of text messages sent in a day, usual allowance in school.

Quantitative Variables can be classified as - It can assume all variables between any two specific values like 0.5, 1.2, etc. and data that can be measured. - weight, height, body temperature.

This is characterized by data that consist of names, labels, or categories only. ✔ gender ✔ most preferred color ✔ usual sleeping time ✔ civil status

This involves data that arranged in some order, but difference between data. ✔ happiness index for the day ✔ highest educational attainment ✔ the rankings of tennis player ✔ Academic Excellence Awards

This is the same in ordinal level, with an additional property that we can determine meaningful amounts of differences between the data. ✔ body temperature ✔ Intelligence Quotient

This is interval level modified to include the inherent zero starting point. ❖ It possesses a meaningful absolute, fixed zero pint and allows all arithmetic operation. ✔ number of siblings ✔ weight

This is done by using chance or random numbers

This is done by numbering each subject of the population and then selecting nth number.

If a population has a distinct groups, it is possible to divide the population into these groups and to draw SRS’s from each of the group.

This method uses intact groups called clusters.

Any data gathered that has not undergone classification is called what?

It is data that has been organized into groups like categories or classes.

What is the most frequently used measure of central tendency?

It is defined as the value of the middle term in the data set that has been arranged in increase order.

It is defined as the value that occurs with the highest frequency in a data set.

It measures how far each number in a data set is from the mean.

It is the difference between the highest and lowest values in a data set.

It is the average of the squared differences from the mean.

It is the square root of variance.

It provides a measure of how spread out the numbers are in a data set.

They are methods or techniques that divide a set of data into equal groups. These measures of position also determine the percentage of the data set that is less than or equal to that specific measure of position.

It is the measure of the likelihood that a certain outcome will occur in a given experiment.

is a set of possible outcomes for an experiment.

It is the process that generates outcomes.

It is the set of all possible outcomes.

It is applied when you can assume each event is equally likely to occur. When you flip a coin, a head or a tail is equally likely to come up. If you have 6 marbles in a bowl and draw one out without looking, anyone of the six marbles has the same chance of being drawn.

is used when you cannot assume each event It is equally likely to occur so you must determine how often like events occurred in the past. Empirical probability is sometimes referred to as relative frequency because you are looking for the frequency of one event in relation to the total number of frequencies.

It is used when each event cannot be assumed to be equally likely and you cannot perform the experiment to determine the relative frequencies. In subjective probabilities, an informed person makes an educated guess. When the weatherman gives the probability of rain tomorrow, he is giving his guess. Subjective probability is only as good as the knowledge the person has who is making the probability.

If two events are ________, it means they cannot occur at the same time

If two events are ________, it means they can occur at the same time together, you might need to subtract the intersection.