Stata histogram overlay example. Here is a simple example using the auto data set.

Stata histogram overlay example tline() is an extension to xline(); see [TS] tsline for examples using tline(). However, if you add the discrete option Stata creates five bins for the five values: hist rep78, discrete The result is a much clearer graph. This technique is commonly used to visually compare the distribution of the dataset to a normal distribution. generate logsaleprice = log Beware! Do not use the Stata command graph bar to obtain a bar graph summary of the distribution of a discrete distribution! Stata does have a command called graph bar, but this does not produce a bar graph summary of a discrete variable distribution. nofill specifies that missing subcategories be omitted. When the text appears, the histogram only shows the male Sep 13, 2023 · My overlays these respective histograms, but of course in the paper the bars for the groups are side by side. Overlapping histograms can be complicated enough with say 2 groups: 5 or 10 is usually a disaster. cales. Kernel Densities Nov 16, 2022 · To view examples, scroll over the categories below and select the desired thumbnail on the menu at the right. Important among these options are ysize(#) and xsize(#), which specify the over-all size of the resulting graph. First, we start with the simple ‘kdensity‘ command kdensity income if year == 1990 Next, we append this command with the ‘addplot‘ function: kdensity income if year Nov 16, 2022 · For other histograms with varying widths, if you have Stata 7 or Stata 6 you can specify bin limits to two community-contributed programs, barplot and hist3. That means that graphical elements on top of each other obscure each other. For instance, consider May 2, 2019 · Performing a Kernel density estimation in Stata is a simple task. Also see [R] histogram for an easier-to-use alter-native. -histogram- supports the -addplot ()- option, so we can add any -twoway- plot to our histogram, and because those plots will be drawn after the histogram bars, they will overlay the bars. By default, elements are not transparent. Because saleprice is right-skewed (for example, type histogram saleprice), we use its log. Moreover, by default, the bins might represent intervals of values (thus, one bin does not necessarily represent one single value) – this depends on the range of values of the variable. Apr 14, 2024 · The “histogram” command also allows users to overlay multiple histograms for comparison. My intuition is that I would need to have my info in only one dataset. com Remarks are presented under the following headings: Typical use Advanced use 1 Advanced use 2 graph twoway function — Twoway line plot of function 3 Aug 31, 2017 · I am trying to plot in Stata a bar graph over different groups of x-values: graph bar characteristics, over (xgroup) Is there a way to easily overlay a vertical bar at a x-value of my choice? May 20, 2025 · Before putting the dataset into an H2O frame, we perform some data manipulation in Stata. This tutorial provides a step-by-step example of how to overlay two histograms in a single plot in Excel. gr bar has the over option, which does this very nicely, but the histogram command lacks this. For instance, if you wished to scale the density estimate as a frequency, area() would be specified as the total number of nonmissing observ Using the -auto- dataset as an example, here is a long way you can create an overlaid histogram of -weight- and -price- with a normal overlay for each - snip - [G-2] graph twoway histogram — Histogram plots arks of StataCorp LLC. Nov 16, 2022 · Home / Resources & Support / FAQs / Stata Graphs / Histogram of continuous variable with frequencies and overlaid normal density curve Histogram of continuous variable with frequencies and overlaid normal density curve Learn about Stata’s Graph Editor Distribution plots As my knowledge, if I create a histogram graph, Stata won't allow me to plot two variables in the same graph. I have tried to follow several threads but I have failed to get the lines and text. But, using the –twoway hist– allows you to use density histograms instead. In the comments, someone asks if it is possible to overlay a normal curve on each histogram, and the author responds with a workaround using a lengthy process instead of twoway. Attached is the example Jul 17, 2020 · Sync to video time Description Overlay Histogram with Fitted Density Curve in Base R & ggplot2 Package (2 Examples) | Kernel & hist 53Likes 6,368Views 2020Jul 17 Up to two over() options may be specified when multiple yvars are specified, and up to three over()s may be specified when one yvar is specified; options may be specified; see Examples of syntax and Multiple over( )s (repeating the bars) under Remarks and examples below. . Let's begin by opening the nhanes2l dataset. com Kernel density estimators approximate the density f(x) from observations on x. Overlapping histograms usually work badly unless you use transparency (as here, requires Stata 15 or later) or remove fill colour. For a histogram, this is trivial; the syntax is: histogram x, frequency Furthermore, if I wished to plot a histogram with a kdensity overlaid and maintain the frequency scaling, I would type: Description Some commands that draw graphs (but do not start with the word graph) are documented in the other reference manuals. dta) that contains the number of calories each of them consumed for 365 days. Forinstance,intheautomobiledata,mpg isacontinuousvariable,butthemileageratingshavebeenmeasuredtointegerprecision Description Quick start Syntax Options for use in the continuous case Remarks and examples Also see twoway histogram draws histograms of varname. For more information, see the Stata Graphics Manual available over the web and from within Stata by typing help graph, and in particular the section on Two Way Scatterplots. For finely spaced da Also see [G-2] graph bar for traditional bar charts and [G-2] graph twoway histogram for histograms. The result is a confusing histogram of fairly simple data. Please let me know. Histograms are bar graphs that depict these frequency counts—the bar is centered at Dec 10, 2021 · Hi Nick Hopefully simple question: I want to show age groups for three different categories but cannot space out the categories on the histogram, also, the width of the bars seem to differ depending on the number of observations ? I have Stata 12. The bin width is 5. I've been trying to create a graph which shows two overlapping histograms - I'm trying to show how the distribution for a quantity if interest has shifted from time A to time B. However, any solution will be appreciated. I would like the to overlay the following twoway graphs with each pair of bars side-by-side as shown in the pictures. The document discusses overlaying histograms in Stata. Learn how to create effective graphs in Stata. In this article, we will learn how to create overlapping histograms in Python using the Matplotlib library. sysuse auto. By changing the transparency, you can see what lies underneath, and that usually produces better-looking graphs. Also see [G-2] graph bar for traditional bar charts and [G-2] graph twoway histogram for histograms. Many of those commands allow the addplot() option. 5 so that we can see the bars underneath. At the end of the year, if they pooled their data together, they would have a dataset (for example, xtline1. Nov 16, 2022 · To view examples, scroll over the categories below and select the desired thumbnail on the menu at the right. Nov 3, 2017 · 1. Also, when twoway graphs are combined with bar, box, and dot graphs, the options affect only those graphs of the same type as the first graph co To view examples, scroll over the categories below and select the desired thumbnail on the menu at the right. How do I merge them into one histogram with the same x-axis and y-axis? grc1leg package is not working. I want to add descriptive statistics to the graph to show the standard errors and median and a separate box showing mean, median, and sd values. Jun 7, 2013 · For example, if you just type: hist rep78 Stata will choose eight bins even though rep78 only has five values. I have following variables in Stata: - lifesatisfaction - temporarywork (1, 2): 1= yes= temporary worker; 0= no Aug 22, 2017 · For example, if IV2 is significant in the model, the code for the scatter plot of the fractional polynomial fit is: " fracplot IV2 if Group==1 " But again, the GUI does not have ' by ' command to plot regression lines separately for each group on the same plot (showing 2 regression lines for 2 groups). See the example that follows. Description Some commands that draw graphs (but do not start with the word graph) are documented in the other reference manuals. Menu Statistics > Summaries, tables, and tests > Distributional plots and tests > Generate cumulative distribution Feb 11, 2023 · Can Stata plot two series with their histograms and kernel densities all in the one chart? something like: twoway (hist x1 || kdensity x1 ) (hist x2 || Apr 25, 2017 · Hi, This is probably a very easy problem but I have been trying to find this out for a while and cant make it work. Go to File -> Example Datasets -> “Example Datasets Installed With Stata”. Jan 30, 2015 · I am not a Stata graphics expert, but it seems that you want some sort of overlay. webuse nhanes2l (Second National histogram—Histogramsforcontinuousandcategoricalvariables9 Histogramsofdiscretevariables Specifyhistogram’sdiscreteoptionwhenyouwishtotreatthedataasdiscrete—whenyouwish eachuniquevalueofthevariabletobeassigneditsownbin. You can type codes in the Stata command window or use a do-file. It is possible to set a few options to make the figure look nice. Single continuous variable Example: Histogram Stata assumes you are working with continuous data Very simple syntax: hist varname Put a comma after your varname and start adding options bin(#) : change the number of bars that the graph displays normal : overlay normal curve addlabels : add actual values to bars Histogram options Apr 24, 2022 · Hello, I overlayed two categorical variables and created an overlapping histogram. Kernel density plots can be obtained using the kdensity command. You can also use twoway graph histogram to create histograms. For example, if I wanted to create a histogram of price, with the y Nov 16, 2022 · Stata allows you to adjust the transparency of elements in graphs it produces. You can make any other changes or specifications you need within this window. Here is a simple example using the auto data set. hist3 is more general, in that it will calculate densities for you. New in Stata 19 Why Stata All features Disciplines Stata/MP StataNow Order Stata Purchase Order Stata Bookstore Stata Press Stata Journal Gift Shop Learn Free webinars NetCourses Classroom and web training Organizational training Video tutorials Third-party courses Web resources Teaching with Stata Support Training Video tutorials FAQs see [G-3] title options. hist mpg, addplot (pci 0 20 . This option allows them to overlay their results on top of graph twoway plots; see [G-2] graph twoway. All references to this section appear in the text as bolded command names, for example, [G-2] graph twoway. Remarks and examples stata. I don't have experience with that approach though. I want the final figure to have two y axis. webuse nhanes2l (Second National Health and Nutrition Apr 3, 2024 · Is it possible to calculate the overlap of two histogram as a percentage? I am using a user-written package called "hist_overlay". I have 6 categorical variables and created 3 overlapping histograms that have the same x-axis and y-axis. 2. It provides code to overlay two histograms on the same graph, with one histogram shown as a red border and transparent fill and the other in default colors. Histograms are actually drawn using twoway rbar with a restriction that 0 be included in the bars; twoway histogram will accept any options allowed by twoway rbar. It is sometimes desirable to make the combined graph wider or longer than usual. The other side, if I create a bar graph, I can't show the percentage of firms on Y-axis. The data are divided into nonoverlapping intervals, and counts are made of the number of data points within each interval. For each of the above, see [G] graph twoway plottype, where you substitute for plottype a word from the left column. Aug 6, 2024 · As mentioned before, because histograms are twoway plots, you can overlay them. It not specially looking to calculate the percentage using "hist_overlay". We can do this with the color (green) option, which sets both the fill color and line color to Nov 6, 2017 · Overlaying histograms in Stata For analysing data and comparing distributions, I often want to overlay two histograms. This is a histogram of cognitive. hist mpg, freq . area() is useful when overlaying a density estimate on top of a histogram that is itself not scaled as a d nsity. , of the combined graph; see [G-3] re-gion options. We have set the "transparency" of the overlay to . These represent the distributions of the read and write variables within the indicated ses level. If you want them side-by-side instead of overlaid, read the help for graph combine. Practical Exercise: Overlay a histogram and Kernel-density plot. Mar 6, 2024 · I used Excel to create this histogram. 0. The process is fairly straightforward in Stata (and even easier in Matlab…). Note also that whereas lfit cannot stand alone (see the example above the graph), it need not be preceded immediately by twoway; it is enough if keyword twoway appears once at the start of the Bar charts are a popular tool used to visualize the frequency or percentage of observations in each group of a categorical variable. webuse ameshouses . Mar 15, 2015 · Graphs We can choose through different kind of graphs in Stata. I have used the command: twoway (bar adultcases year, barwidth (0. twoway /// Feb 27, 2023 · Also, this code will only render frequency histograms, not density histograms, which are the default in Stata. I want to overlay a twoway graph from data A over an histogram from data B (or vice-versa). I have a continuous variable (optical density of a haemorrhage=DfrontalLR) for which I want to create histogram, which is not the problem. Both histograms were rendered in the same color. Let’s change the female histogram color to green. Here are Nov 16, 2022 · Create publication-quality statistical graphs with Stata: many graph styles to choose from, distributional diagnostic plots, ROC curves, spike plots, multivariate graphs, different output formats, and much more. As you Sep 23, 2009 · If you want to compare kernel density estimates across years for a particular variable, putting each estimate on one graph will make it easy. Default Stata allows users to construct overlaid histograms using the -twoway- graph command. They could then use xtset to identify the date variable and treat each person as a panel and use xtline to plot the Relationship between graph twoway histogram and histogram graph twoway histogram—documented here—and histogram—documented in [R] histogram—are almost the same command. See Combining twoway graphs under Remarks and examples raphs. Sep 25, 2023 · The kernel density smoother fits a smooth line over this histogram. Let's begin by opening the nhanes2l dataset and using tabstat to view the minimum, maximum, 25th, 50th, and 75th percentiles of age for each Description and is useful as a programming tool. May 13, 2020 · I want to plot a histogram showing how many judges graduated from each law school, by judge's birth cohort. commands used for the graph twoway histogram agegroup if var1==1, color (blue) percent|| histogram agegroup if Jul 23, 2020 · Histograms You can also use a histogram to look at your data. region options allow you to control the aspect ratio, size, etc. This data contains a 3-level categorical variable, ses, and we will create histograms and densities for each level. Instead, it produces a bar graph plot of selected statistics of a continuous variable (usually the mean). You can use Stata's graph box command to create simple box plots, or you can add options to make more sophisticated charts. 1 20) In the -addplot()- option, we specified the immediate form Overview multihistogram allows Stata users to easily construct overlaid histograms with aligned bins in Stata. For instance, if you wished to scale the density estimate as a frequency, area() would be specified as the total number of nonmissing observations. To create a histogram using drop-down menus, you will go to Graphics -> Histogram. com Remarks are presented under the following headings: Histograms of continuous variables Overlaying normal and kernel density estimates Histograms of discrete variables Use with by() Video example For an example of editing a histogram with the Graph Editor, see Pollock (2011, 29–31). Thanks, Ty Mar 12, 2014 · That plot already overlaps three different plots (scatter for the dots, rcap for the vertical lines, and line for the horizontal lines). Aug 12, 2025 · This module will introduce some basic graphs in Stata 12, including histograms, boxplots, scatterplots, and scatterplot matrices. In particular it can be visualized by way of a kernel density plot which we will look at here… 3Examples Bivariate histogram Trivariate distributions Display values as marker labels Correlation matrix Spacial weights matrix Dec 7, 2023 · I wish to draw a histogram with a normal density plot and a line indicating the mean value. hist rep78, freq However, if the variable you are graphing takes on noninteger values, this command will not work. Remarks and examples Kernel density estimators approximate the density () from observations on . The demo data is only 10% of the data used to produce the Excel graph above. Explore graphing techniques, examples, and tips for better data visualisation in your research. Nick [email protected] Alejandro Delafuente > am would like to overlap two histograms, > can anyone tell how > to do so? Jul 1, 2024 · Overlaying two histograms in Stata refers to the process of creating a single histogram that displays the data from two separate histograms on the same graph. Oct 15, 2022 · A histogram is a plot that can be used to quickly visualize the distribution of values in a dataset. Click on the ‘use’ option in front of the dataset name in the list Mar 4, 2018 · Hi, I realise this is most likely an elementary question, but I cannot find a solution. The default is that the y-axis shows the density of values across the x-axis. The default is area(1). Actually, in this particular case, there is a way we can combine that, too: This module shows examples of the different kinds of graphs that can be created with the graph twoway command. Oct 7, 2025 · Conclusion It is concluded that a histogram is a graphical representation in which researchers check the frequency distribution along with the normality of the dataset. The y-axis should show the proportion in %. I am using Stata 18 I have used the following code (to obtain the mean value) and try to draw the normal density plot (dlwg6 is the continuous variable of interest) summ dlwg6 local a= r (mean) hist dlwg6, normal gap (5) xline (`a') however with the above command I get the plot without the xline But if The third example did not change: in that example, we are combining a scatterplot and a line plot. Example code: Jul 23, 2025 · Histograms are used to represent the frequencies across various intervals in a dataset. Just FYI, I posted this same question here but did not get a response: I made up demo data if anyone wants to help me to make the graph. com Learn how to create histograms with frequencies and overlay normal density curves using Stata's graphing tools for visualizing continuous variables. We also generate a variable, houseage, that calculates the age of the house at the time of a sales transaction. It's reasonable that nearly similar distributions overlap mightly, but the graph is still likely to seem a See full list on github. Based on my copy of A Visual Guide to Stata Graphics, you might try something like the following: twoway (histogram iq, etc etc) (line x y) where line shows your normal curve. Feb 9, 2015 · Is there a way to force the added vertical line placed by the xline (0) option to lay over the top of the histogram bars rather than behind the bars as shown here? The other annotation, of a normal density curve is already in the foreground. hist mpg, addplot(pci 0 20 . You can use Stata's graph bar command to create simple bar charts, or you can add options to make more sophisticated charts. In R, this can be achieved by using the “curve” function to plot the normal curve on the same graph as the histogram Description twoway is a family of plots, all of which fit on numeric and scales. dta The histogram command can be used to make a simple histogram of mpg histogram mpg If you are creating a histogram for a categorical variable such as rep78, you can add the option discrete. Let’s use the auto data file for making some graphs. Just keep on going with the command, adding in each part you want to overlay. bin(#) • width(#) • density • fraction • frequency • percent • addlabels addlabopts(<options>) • normal • normopts(<options>) • kdensity kdenopts . Jun 21, 2023 · I’m using Stata BE/17. You can also use the –twoway hist– command to overlay two bar graphs, but these might not perfectly align with the deciles. If you work out the proper code please share! Nov 16, 2022 · Histograms are a popular tool used to visualize the distribution of a continuous variable. I use STATA 17 btw. hist () function will be used to plot these histograms so that we can compare different sets of data on the same chart. Use the twoway command to overlay the kernel density plot and histogram. This is useful when you want to compare the distribution of a variable across different groups (Low number of groups). area() is useful when overlaying a density estimate on top of a histogram that is itself not scaled as a density. However, when multiple histogram graph types are specified, bins are constructed separately for each series. In this example, we can see that the variable is approximately normally distributed (with a The histogram is 19th century technology: you can do much better with 1960s technology, namely the quantile-quantile plot implemented as -qqplot-. In this dialogue box you need to specify which variable you are looking at in the “Variable” box. Putting two histograms on one graph is not the problem twoway (histogram myvarA) (histogram myvarB) but the problem is that one obscures the other. Furthermore, Stata offers additional commands such as “histogram options” and “graph combine” to further customize and combine histograms. -histogram- supports the -addplot()- option, so we can add any -twoway- plot to our histogram, and because those plots will be drawn after the histogram bars, they will overlay the bars. Here we will focus only on histogram. pyplot. This is illustrated by showing the command and the resulting graph. The x-axis should show the satisfaction of life on a scale from 0 (not satisfied) to 10 (very satisfied). 5)) (bar childcases year, barwidth (0. Stata and Stata Press are registered trademarks with the World Intellectual Property Or-ganization Frequency plots can be made in Stata using the hist command with the freq option. The code below creates overlaid histograms. Histogram If we want to control the density of a variable or its frequency distribution, we can type: histogram price Mar 27, 2017 · Hello, I am using Stata 14. Note that for overlaying, at least command keyword twoway is required (graph twoway is also possible). That is, you cannot simply start with scatter. Jan 27, 2025 · This guide provides instructions to generate basic figures/graphs using Stata that are useful for exploratory data analysis. 1 and thus cannot add transparency. Is it feasible with two separate datasets using a saved graph/histogram? Any suggestions? Data A (twoway graph Histograms are a common way of graphically representing the frequency distribution of data. But the variable (optical density) should be divided/split based on another variable (haemorrhage yes/no=CTresult). Histograms do this, too, and the histogram itself is a kind of kernel density estimate. Stata overlaid a normal curve on a histogram by using the sample mean and standard deviation, using the probability density function and scaling it to the axis of the histogram. Jun 29, 2024 · Overlaying a normal curve on a histogram in R refers to the process of superimposing a bell-shaped curve over a graph that displays the distribution of a dataset. describe headroom storage display value variable name type format label variable label Styles, concepts, and schemes This section is arranged alphabetically by graph subcommand and documents all the families of graphs (for example, two-way, bar, or box) and the graph management commands (for example, graph drop or graph use). Nov 16, 2022 · Box plots are a popular tool used to visualize the distribution of a continuous variable for each group of a categorical variable. import library Example 1 Suppose that Tess, Sam, and Arnold kept a calorie log for an entire calendar year. Jul 20, 2023 · Dear All, I am creating an overlapping histogram to show the difference in log wages for males and females. In this article we are going to learn how to create Histogram in Stata Let’s load one of Stata’s inbuilt datasets to see how histograms are created. Beware! Do not use the Stata command graph bar to obtain a bar graph summary of the distribution of a discrete distribution! Stata does have a command called graph bar, but this does not produce a bar graph summary of a discrete variable distribution. Sep 3, 2017 · The three different bars in the histogram should show (1) standard employment relationship, (2) temporary workers and (3) unemployed. Oct 16, 2020 · This tutorial explains how to create and modify histograms in Stata by using several examples. I am using: twoway (histogram j_lawschool_num if j_cohort_num == 1 | j_cohort_num == 2, The default is area(1). Without further options, however, one distribution usually overlays the other and makes comparisons cumbersome. You can use Stata's histogram command to create simple histograms, or you can add options to make more sophisticated charts. twoway (histogram write if female==1, start(30) width(5)) /// (histogram write if female==0, start(30) width(5)) Well, that didn’t work out so well. 1 20) Feb 20, 2015 · 0 I am trying to plot a kernel density of a single variable in Stata where the y-axis is displayed as a frequency rather than the default density scale. 5)) Thanks, Scott Jul 26, 2021 · In this example, we show two methods to overlay histogram distributions using seaborn and matplotlib separately. Description yline(), xline(), and tline() are used with twoway to add lines to the plot region. The common ones are histograms and scatterplots but we will study also boxplots in order to gain a comprehensive understanding of every disposable tool. I have also attached what my current graph looks like. The matplotlib. histogram has the advantages that otted. To view examples, scroll over the categories below and select the desired thumbnail on the menu at the right. I have several histograms to make, so help with Stata code will be greatly appreciated. Aug 22, 2019 · How can I achieve a 2x4 orientation of histograms? I have played around with the aspectratio() option, but this changes the aspect ratio of the individual graphs, not of the whole plot. sysuse auto . [G-3] saving option). Let's begin by opening the nhanes2l dataset and tabulating the variable hlthstat. 2 I would like a histogram of mean (intercepts) for my metabolite, with the overall mean and standard deviation overlayed. fkrjr rmqzsk qkpq lqvaw nxhu vppci dqbfoqq pbnqjgm dey miq ksse hedoj pdz uvdubu ihagsa