Inferential Statistics
3ER PARCIAL
Inferential statistics
Sampling
* The purpose of sampling is to select a set of elements (sample) from a population that we can use to estimate parameters about the population * The bigger the sampling, the more accurate our parameters will be. example: In the experiment of deciding if CEGL girls are smarter that CEGL boys, which would be your statistical hypothesis?
Hypothesis testing
But now, you already gathered information about a sample
No, you will test if your hypothesis are true or not
Hypothesis testing involves testing the difference between a hypothesized value of a population parameter and the estimate of that parameter, calculated from the sample
example: If you want to know if CEGL girls are smarter that CEGL boys, you ask a few girls/boys their grades and compare averages, we will use Excel to compare the population and sample means. If the difference is too high, we can’t compare.
In statistics, the hypothesis to be tested is called “null hypothesis” and has the symbol “Ho”
The other option of the hypothesis is the “alternative hypothesis” and its symbol is “Ha”
1 Ho: “There is no difference between (independent variable) and (dependent variable)” 2 Ha: “There is a difference between (independent variable) and (dependent variable)”
example:
In the experiment of deciding if CEGL girls are smarter that CEGL boys, which would be your statistical hypothesis?
Ho: There is no difference between Gender and Grades
Ha: There is a difference between Gender and Grades
How to decide between Ho and Ha?
A decision must be made on how much evidence is necessary to accept a hypothesis.
If a hypothesis is that the world’s average is 23 and you only choose one person of 58 years, you wouldn’t decide basen of that..
We use statistical tests (excel) to determine the correct hypothesis.
The value we use to determine if we keep Ho or Ha is called the level of significance (ALPHA):
If we choose alpha=1%
Inferential statistics
Sampling
* The purpose of sampling is to select a set of elements (sample) from a population that we can use to estimate parameters about the population * The bigger the sampling, the more accurate our parameters will be. example: In the experiment of deciding if CEGL girls are smarter that CEGL boys, which would be your statistical hypothesis?
Hypothesis testing
But now, you already gathered information about a sample
No, you will test if your hypothesis are true or not
Hypothesis testing involves testing the difference between a hypothesized value of a population parameter and the estimate of that parameter, calculated from the sample
example: If you want to know if CEGL girls are smarter that CEGL boys, you ask a few girls/boys their grades and compare averages, we will use Excel to compare the population and sample means. If the difference is too high, we can’t compare.
In statistics, the hypothesis to be tested is called “null hypothesis” and has the symbol “Ho”
The other option of the hypothesis is the “alternative hypothesis” and its symbol is “Ha”
1 Ho: “There is no difference between (independent variable) and (dependent variable)” 2 Ha: “There is a difference between (independent variable) and (dependent variable)”
example:
In the experiment of deciding if CEGL girls are smarter that CEGL boys, which would be your statistical hypothesis?
Ho: There is no difference between Gender and Grades
Ha: There is a difference between Gender and Grades
How to decide between Ho and Ha?
A decision must be made on how much evidence is necessary to accept a hypothesis.
If a hypothesis is that the world’s average is 23 and you only choose one person of 58 years, you wouldn’t decide basen of that..
We use statistical tests (excel) to determine the correct hypothesis.
The value we use to determine if we keep Ho or Ha is called the level of significance (ALPHA):
If we choose alpha=1%
References: * Also, the specific poster needs to have attention to design: * It has an appealing background that allows easy reading. * It includes tables, diagrams, drawings with appropriate labels. * It is not made by hand. ORAL PRESENTATION * Designed to explain in full detail your research. The oral presentation’s target audience is not the general public. The oral presentation includes all the sections of the scientific report. * A scientific poster may help for an oral presentation but it is not mandatory * Never try to learn by hard the contents, it shows. * Never fill your PPT with paragraphs text, it is boring. * You may read some words or sentences, but reading a paragraph and moving on, no.