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## SAT

### Course: SAT > Unit 6

Lesson 5: Problem Solving and Data Analysis: lessons by skill- Ratios, rates, and proportions | Lesson
- Percents | Lesson
- Units | Lesson
- Table data | Lesson
- Scatterplots | Lesson
- Key features of graphs | Lesson
- Linear and exponential growth | Lesson
- Data inferences | Lesson
- Center, spread, and shape of distributions | Lesson
- Data collection and conclusions | Lesson

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# Data collection and conclusions | Lesson

## What are data collection and conclusion problems, and how frequently do they appear on the test?

We routinely conduct research to answer questions such as "how many residents are in favor of a new law" or "is a new medical treatment effective?" While research results can give us powerful insights, we must carefully consider

*how*the research is conducted, which in turn affects*what*conclusions can be drawn.For example:

- If a survey was given to individuals of one ethnicity, then the results of the survey are
*not*representative of individuals of other ethnicities. - If a medical treatment is effective when tested on mice, we
*cannot*conclude that the treatment is just as effective on humans without additional testing.

We won't be required to perform any calculations in data collection and conclusions problems. Instead, we'll be asked to read fairly lengthy descriptions and then make logical observations or draw valid conclusions.

In this lesson, we'll learn to:

- Recognize good and bad sampling methods
- Draw valid conclusions from the results of surveys and experiments

On your official SAT, you'll likely see

**1 question**that tests your understanding of data collection methods as well as survey and experiment results.**You can learn anything. Let's do this!**

## What are some good and bad sampling methods?

### Reasonable samples

### Examples of bias in surveys

### Example of "undercoverage" bias

### Sampling methods and their implications

Ideally, a provides information about a without having to survey the entire group.

To make valid conclusions about a population, we need a sample that recreates the characteristics of the entire population on a smaller scale.

A

*good*sample is**representative**and**random**.- Representative means that the sample includes only members of the population being studied.
- Random means that every member of the population being studied has an equal chance to be selected for the sample.

*Bad*sampling methods include those that:

- Gather data from outside the population being studied
- Gather data that overrepresent or underrepresent a subgroup of the population (not random)

### Try it!

## What are some different types of studies, and what conclusions can we draw from the results?

### Types of statistical studies

### Correlation and causality

### Identifying study types

### Drawing conclusions from study results

#### Sample surveys

We can draw conclusions about

*only*the population from which the random sample was selected.#### Controlled experiments

To understand the conclusions we can draw from controlled experiments, we must first understand the difference between

**correlation**and**causation**.- Correlation means there is a relationship or pattern between the values of two variables.
- Causation means that one event causes another event to occur.

You may have learned about controlled experiments and the scientific method in more detail in your science classes. For the SAT, the key takeaway is that a is needed to establish a causal relationship.

### Try it!

## Your turn!

## Want to join the conversation?

- This topic is a bit complicated and slow.....can you guys put in more exercises .....?(21 votes)
- Are the types of bias on the SAT?(8 votes)
- They're not tested by name. For example, you'll never have to answer a question like: "What is an example of an undercoverage bias". However, it would be good to keep the types of bias in mind, as some SAT questions do test you on if a sampling method is fair or not, and it would help to know the types of biases so that you could tell which methods would be wrong. Above all, you just need to keep in mind that good sampling involves asking a random collection of the same people who are representative of the whole, and that a bigger sample size is more accurate.(3 votes)

- Can you maybe put what the types of bias mean?(6 votes)