Scatter Plot
What is a scatter plot?
A scatter plot uses individual data points to display the relationship between two separate numerical variables. Each point on the plot represents a single observation, with its position determined by its values on the horizontal and vertical axes. Scatter plots are primarily used to identify patterns, data clusters, or relationships between variables.
Scatter plots are great for data exploration. By observing patterns in the plot, you can discern the type of correlation present: positive (points trend upwards), negative (points trend downwards), or null (points show no clear trend). They are also excellent at visualizing the dispersion and clustering of the data, and can even help spot outliers that deviate from general trends.
First-class support for visualizing error
Data transparency is important and that's why Graphmatik scatter plots help you display uncertainty in your data by default. Graphmatik will automatically calculate the neccessary summary statistics from replicate values and display error bars by default.
on/off
to suit your preferences.Simple regression analysis
Easily add a line of best fit to scatterplots. Graphmatik can fit linear, polynomial, exponential, logarithmic, and power trendlines via "Ordinary Least Squares" (OLS) regression. Estimated equation parameters and R-squared values (i.e. coefficient of determination) can be found in the stats workspace
.
Interpolate from a curve
It is easy to interpolate from a regression curve in Graphmatik. After running an analysis, switch to the stats workspace and select the interpolate tab. A table will appear where you can enter values into X or Y columns.
Provide a value for X, and Graphmatik will interpolate a value for Y. Enter a value for Y, and Graphmatik will estimate the corresponding value of X.
X | Y |
---|---|
1 | 3.5265 |
2 | 4.6003 |
5 | 7.8215 |
11.685 | 15 |
20.998 | 25 |
Tips for creating beautiful scatter plots
Chart properties
Prop | Default | Description |
---|---|---|
central tendency | mean | mean The sum of a set of values divided by the number of values in the set. median The middle most value of a sorted set of numbers. |
error | SEM | standard error of the mean (SEM) How much the sample means vary from the population mean. mean standard deviation (SD) A measure of the variation of a set of values around their mean. mean 95% confidence interval (95% CI) 95% probability that the population parameter lies within this range. mean or median range The difference between the highest and lowest values within a set. mean or median Interquartile range (IQR) The middle 50% of a set of values (i.e. 3rd quartile - 1st quartile).median |
radius | med | slider Change the size of the points between small, medium, and large. |
opacity | 100% | slider Change the opacity of the points. |
regression | linear | linear Fit a straight line to the data. polynomial Fit a curved polynomial trendline to the data. Graphmatik supports up to 10th order polynomials. exponential Fit a curved exponential line to the data. Best for when the data increases or decreases at increasingly higher rates logarithmic Fit a curved logarithmic trendline to the data. Best for when data increases or decreases quickly then levels out. power Fit a curved power trendline to the data. Best for when the data increases at a specific rate. |