Notes g7
Notes g7
Notes g7
Lesson 1
Statistics is a branch of Applied Mathematics specializing in procedures for collecting,
organizing, presenting, analyzing, and interpreting data from observations.
Statistics involves much more than simply drawing graphs and computing averages.
• In education, it is frequently used to describe test results.
• In science, the data resulting from experiments must be collected and analyzed.
• Manufacturers can provide better products at reasonable costs through the use of
statistical quality control techniques.
• In government, many kinds of statistical data are collected all the time.
• A knowledge of statistics can help you become more critical in your analysis of
information; hence, you will not be misled by manufactured polls, graphs, and averages.
A statistical question is one that can be answered by collecting data that vary.
There are two types of data: numerical and categorical. Numerical data set are those in
numerical form which are either continuous or discrete. Discrete data are those that can be
counted in a finitely while continuous data are measurements that can take any value from an
is infinite range. Categorical data take nonnumerical values, such as colors, information or
questions that are answerable by YES or NO, labels, etc. (example: large, medium, and small)
The 4 steps below can be followed to solve real life problems using statistics
1. Pose the question that can be answered by data.
2. Determine a plan to collect data.
3. Organize and summarize the data.
4. Interpret the results and answer the question posed in Step 1 using the organized and
summarized data.
Lesson 2
There are different statistical instruments that can be formulated and used to gather data
depending on the needs. Listed below are some of the statistical instruments.
Observation - it focuses in determining the changes in the attitude, characteristics and behavior
of people or other subjects. This technique includes watching and recording actions and
behaviors.
Interviews - it is being performed through personally asking questions to people who have the
authority or expertise to say something about the data needed. The person gathering the data is
called the interviewer, while the person supplying the data is the interviewee.
Focus Group Discussion (FGD) - it is used to know the thinking, feeling or opinion, about a
certain phenomenon, idea and etc. FGD is conducted with a small group of people with
common knowledge and common field (usually 6 to 8 people).
Questionnaire - if you have big number of samples, it is the most practical way to use. You
gather data through writing. However, you must be careful presenting your questions, since we
need to consider the culture, and characteristics of the respondents. You may use email, letter,
or personally give your questionnaire to your respondents.
Using different questions, and approaches to questioning, can allow us access to the information
we require. Questionnaires usually are comprised of a number of questions that can either be
closed questions, open-ended questions, or multiple choice.
Types of Questions
1. Closed questions
These are questions which can be answered with “Yes” or “No,” or they have a limited set of
possible answers (such as: A, B, C, or All of the above). For example, ‘Do you wear glasses?’
the respondent either does (responding ‘yes’) or doesn’t (responding ‘no’) wear glasses.
2. Open-ended questions
These are questions that allow someone to give a free-form answer.
Example, “How did you answer the modules?”
3. Multiple-choice questions
These are questions that provide a certain number of specific response options as possible
answers. An example of multiple-choice question would be:
“How do you spend your free time?”.
a. reading c. surfing the internet
b. listening to radio d. watching TV e. others (please specify: __)
Survey – in a national level, surveys are usually covered by the government and other form of
surveying organization such as National Statistics Office (NSO). A survey can also be done in
small scale (i.e. a class of 25 students can be surveyed)
Lesson 3
Collection of data is an important part of Statistics. Data should be collected in a manner that
they are accurate and convenient to use.
Data is a collection of facts or information. They may be gathered by using the following
methods.
1. Conducting Surveys
Example: Teacher made a form and ask the students to fill out the previous grades
and return the form to him/her.
2. Observing the Outcomes of Events
Example: Jessa wanted to find whether a die was fair or biased. She tossed the die
40 times and recorded the results.
3. Taking measurements in experiments
Example: The physicist and chemist conducted an experiment on how can saw
dust be substituted for sand in the production of hollow blocks.
4. Reading Statistical Publication
Example: Mr. Rivera check the date of birth of each student in the class registry.