# Scattergrams relationship

### Describing scatterplots (form, direction, strength, outliers) (article) | Khan Academy Scatter Plot with No Relationship, scatter plot showing no relationship. Discussion, Note in the plot above how for a given value of X (say X = ), the. A scatterplot is used to graphically represent the relationship between two variables. Explore the relationship between scatterplots and. Scatterplot. ▫ The most useful graph for displaying the relationship between two quantitative variables is a scatterplot. ▫ Many research projects are correlational.

So first, before looking at the explanations, let's look at the actual graphs. So this one on the left right over here, it looks like there is a positive linear relationship right over here. I could almost fit a line that would go just like that. And it makes sense that there would be, that the more time that you spend studying, the better score that you would get. Now for a certain amount of time studying, some people might do better than others, but it does seem like there's this relationship. Here it doesn't seem like there's really much of a relationship. You see the shoe sizes, for a given shoe size, some people do not so well and some people do very well.

### What is a Scatter Plot and When to Use It

Someone else, looks like they got A minus or a B plus on the exam. And it really would be hard to somehow fit a line here.

No matter how you draw a line, these dots don't seem to form a trend. So let's see which of these choices apply.

## What is a Scatter Plot and When to Use It

However, they have a very specific purpose. Scatter plots show how much one variable is affected by another. The relationship between two variables is called their correlation.

Scatter plots usually consist of a large body of data. The closer the data points come when plotted to making a straight line, the higher the correlation between the two variables, or the stronger the relationship. If the data points make a straight line going from the origin out to high x- and y-values, then the variables are said to have a positive correlation. If the line goes from a high-value on the y-axis down to a high-value on the x-axis, the variables have a negative correlation. A perfect positive correlation is given the value of 1.

An equation for the correlation between the variables can be determined by established best-fit procedures.

### Scatter plot - Wikipedia

For a linear correlation, the best-fit procedure is known as linear regression and is guaranteed to generate a correct solution in a finite time. No universal best-fit procedure is guaranteed to generate a correct solution for arbitrary relationships.

Statistics - Making a scatter plot

A scatter plot is also very useful when we wish to see how two comparable data sets agree to show nonlinear relationships between variables. The scatter diagram is one of the seven basic tools of quality control. The researcher would then plot the data in a scatter plot, assigning "lung capacity" to the horizontal axis, and "time holding breath" to the vertical axis. The scatter plot of all the people in the study would enable the researcher to obtain a visual comparison of the two variables in the data set, and will help to determine what kind of relationship there might be between the two variables.