Stata margins standard deviation


Stata margins standard deviation

stata margins standard deviation If you select Estimate margins of error, enter a value for the sample size. On this site, we use z-scores when the population standard deviation is known and the sample size is large. Slow Fading Margin in LTE with example of standard deviations in slow fading, signal strength at different test points, standard deviation of slow fading. up vote 7 down vote A standard normal distribution is a normal distribution with mean 0 and standard deviation 1. 3 above were changed to 1. A distribution with a low SD would display as a tall narrow shape, while a large SD would be indicated by a wider shape. Normal data with mean 0 and standard deviation 1: (this is by no means an exhaustive list of all Stata commands): read non-Stata-format dataset (ASCII or text Find out how to distinguish between mean, standard deviation, standard error and relative standard error in statistical survey samples. Simons Throughout, estimation commands specify robust standard errors (Eicker-Huber-White From what you were saying it sounds as though confidence intervals don't really apply here - I could work out a confidence interval using this one sample (using the sample standard deviation instead of the population standard deviation, which I don't know) but the results would be meaningless since I can't sample from the population many times? (This assumes a normal distribution on large n; standard deviation known. 35. R how to calculate standard deviation of certain columns in data frame Your intuition is correct. The secret to making the floating chart is to use the column chart in an effective way by selecting the Step 1 – Add two columns X and Y . collapse is the Stata equivalent of R's aggregate function Population Standard Deviation The population standard deviation is measures the variability of data in a population. all by itself, Stata will calculate the Introduction to Stata and Hypothesis testing. 5 on some key variable. error, or uncertainty in a reported measurement. We have already seen how easy this is to achieve in Stata. mean2 and std2 compute the mean and standard deviation of the elements of a matrix. I appreciate any help. 1 Standard Errors of Mean, Variance, and Standard Deviation Estimators Sangtae Ahn and Jeffrey A. Another way of looking at Standard Deviation is by plotting the distribution as a histogram of responses. The standard deviation is the root mean square (RMS) deviation of the values from their arithmetic mean. How to Determine Sample Size With Mean & Standard Deviation By Mark Stansberry; Updated March 14, 2018 If the sample size is too small, the sample data obtained will not be an accurate reflection of the data that is representative of the population. Hello, I would like to ask a question about the stdp and stdf commands. Value at Risk Standard Deviation What does standard deviation tell us that variance doesnt? Discrete Random Variable Not much Continuous normal Z-scores are a type of descriptive statistics. They give Read and learn for free about the following article: Calculating standard deviation step by step Standard Error Calculation 9/22/04 STANDARD ERROR CALCULATION Procedure: Step 1: Calculate the mean (Total of all samples divided by the number of samples). In statistics it is referred to as the 1 Computing the Standard Deviation of Sample Means Quality control charts are based on sample means not on individual values within a sample. The question emerged from Stata output, but I'm interested in the general issue of calculating the t-value for the margins. getting the standard deviation of predictions. Making Regression Tables in Stata. 60 times the SD to 2. Z-scores are a type of descriptive statistics. if your independent variables are just the group variables (categorical variables that indicate which observation is in each group) you can use the command: vwls yvar xvarlist The Standard deviation is a common statistical calculation used to determine how much the individual samples in a data set vary from the mean (or average) of the data Image Mean, Standard Deviation, and Correlation Coefficient You can compute standard statistics of an image using the mean2 , std2 , and corr2 functions. σ (Greek letter sigma) is the symbol for the population standard deviation. Rolling standard deviations. Looking specifically at range, variance, and standard deviation, this lesson explores the relationship between these measures and samples, c. Descriptive statistics standard deviation). Within and between subgroup variation (total standard deviation) is used in calculating Pp, Pr, and Ppk. When you execute the command, an existing data set is replaced with the new one containing aggregate data. 5 standard deviations away from the mean". From the n=5 row of the table, the 95% confidence interval extends from 0. weighted variance is computed in Stata for analytic and sampling weights, very useful material for understanding STATA without waistin your money by suchitjack in Types > Presentations This MATLAB function returns the standard deviation of the data in a timeseries object. Z-scores represent the number of standard deviations between each data point and the mean. The standard deviation (often SD) is a measure of variability The last parameters we need to find confidence intervals for are the population variance (σ 2) and standard deviation (σ). Multiply coefficients with standard deviation Tag: r , stargazer In R , the stargazer package offers the possibility to apply functions to the coefficients, standard errors, etc: For a population with unknown mean and known standard deviation , a confidence interval for the population mean, based on a simple random sample (SRS) of size n, is + z *, where z * is the upper (1-C)/2 critical value for the standard normal distribution. g. Statistics Question How to combine and divide data points with margins of error? and then use that to calculate standard deviation. SPSS. Variance Definition: The square of the standard deviation. On the average, a random variable misses the mean by one standard deviation. Poll results are accompanied by a margin of error but how is it calculated? It's a statement of the sample size and level of confidence. We Command to Estimate and Interpret Adjusted Predictions and Marginal Effects Richard Williams well with both older Stata commands and the newer margins command New methods of interpretation using marginal Post-estimation with margins and lincom 5. The secret to making the floating chart is to use the column chart in an effective way by selecting the Step 1 – Add two columns X and Y If an array is passed, it must be the same length as the data. by Tommy Charles; Updated May 16, 2018. 1 The contrast between these two terms reflects the important distinction between data description and inference, one that all researchers should appreciate. 6%, you need four times as big of a Describes how the standard deviation (sigma) is estimated using a control chart Stata's collapse command computes aggregate statistics such as mean, sum, and standard deviation and saves them into a data set. For example, a common estimator of the population mean of Z, denoted [bar. But how accurate is that How do you annualise the covariance, mean, variance and standard deviation of a data set? Hi Experts, It is very difficult to source a reliable answer to the above question. Tell us where you got Detecting outliers: Do not use standard deviation around the mean, use absolute deviation around the median Author links open overlay panel Christophe Leys a Christophe Ley b 1 Olivier Klein a Philippe Bernard a 1 Laurent Licata a Now the standard deviation of the second data set is just going to be the square root of its variance, which is just 2. while if I try to replicate this using Stata's margins, this is the result: Finding the standard deviation of a Predicted probabilities and marginal effects after (ordered) logit/probit using margins in Stata (v2. Have you looked at the post-estimation margins, folllowed by marginsplot?This is as good as it gets for plotting results from any regression-type model in Stata. What is the 95% confidence The standard deviation is the square root of the variance. 87 times the SD. Making Tables and Figures between columns so the width of the table fits appropriately between the margins. Standard deviation is a common statistical calculation used to determine how much the individual samples in a data set vary from the mean (or average) of the data Expectation, Variance and Standard Deviation for Continuous Random Variables Class 6, 18. Difference Between Gross Profit Margin and Standard Margins. The sample standard deviation computed from the five values is 3. Step 2 Q: How I calculate industry mean or standard deviation of returns? In accounting research, we have to calculate industry means and standard deviations. 63. The p-value is the probability that you have falsely rejected the null hypothesis. Fit all of one Standard APA format for journal The principle of estout is simple: you run a command in Stata that generates some statistics, you tell estout to (temporarily) store those results and then you create a table. The variance, which the standard deviation squared, is nicer for algebraic manipulations. Stata: Descriptive Statistics - Mean, median, variability Suppose we want to get some summarize statistics for price such as the mean, standard deviation, and range. In Stata, search eusmex2016 to download Increasing BMI by one standard Learning Objective: 1) understand the difference between marginal and conditional standard deviation. Weighted variance, standard deviation, covariance & correlation. But how accurate is that Calculating Standard Deviation is fairly easy in Excel. Sample sizes were determined Working with Probability Models 1. I'm trying to figure out what is the meaning of standard deviation with regard to dummy variables. , they represent how much variation there is from the average, or to what extent the values typically "deviate" from the mean (average). 52) Stat > Power and Sample Size > Sample Size for Estimation. Related Articles. standard deviation is based on normality assumption and uses approximation of expected values of the order statistics. I'm doing a customer survey where people have responded: Agree strongly 331 Agree somewhat 100 Neither 50 Disagree somewhat 10 Disagree strongly 5 I want to assign a 1 to 5 score to each response (1=agree strongly) and get the weighted average standard deviation using just the frequencys above. But how accurate is that Rolling standard deviations and missing observations Posted on 31 March 2014 by Mitch Abdon In And we’re rolling, rolling; rolling on the river , Hasan asked how he could “keep only those values that were calculated using at least 3 observations” after he calculated the 4 period rolling standard deviation of a set of observations. Standard errors are margins. margins, dydx(*) atmeans Trivedi suggest using the standard deviation of the variable divided by 1000. coefficient of variation calculator - to find the ratio of standard deviation (σ) to mean (μ); along with formula, example & complete step by step relative variability calculation Point Estimate: • a specific value that estimates a parameter • e. The variance and the standard deviation give us a numerical measure of the scatter of a data set. The other sample had 12 subjects and had a standard deviation of 6. If the differences themselves were added up, the positive would exactly balance the negative and so their sum would be zero. The area under the curve over this range is the relative frequency of observations in the range. I have 3 sets of data and I need to add standard deviation on any individual one. Impulse Response Function in STATA As the footnotes indicate, the first column displays the responses of GDP to one standard deviation shock in e GDP. Home > error bars > representing standard deviation error bars Representing Standard Deviation Error Bars. This, it seems, is true with how Stata calculates the standard deviation for the margins with the delta method. So the second data set has 1/10 the standard deviation as this first data set. 5 it is interpreted as "+2. Therefore, is the expected size of the miss when is used to estimate . Areas under this curve can be found using a standard normal table (Table A in the Moore and Moore & McCabe textbooks). 4. Stata has a lot of multilevel modeling capababilities. 52) Summary statistics, Histogram, Box/Dot/Mean/Normal plot The mean is a measure of the central location of the sample and the standard deviation is a measure of the The standard deviation is a summary measure of the differences of each observation from the mean. Thankfully, Stata has a beautiful function known as egen to easily calculate group means and standard deviations. Rolling standard deviations and missing observations Posted on 31 March 2014 by Mitch Abdon In And we’re rolling, rolling; rolling on the river , Hasan asked how he could “keep only those values that were calculated using at least 3 observations” after he calculated the 4 period rolling standard deviation of a set of observations. The 1-inch margin all around is a default setting characteristic of Microsoft Word and most of the other word processor documents, according to Butterick's View 06-Stat Rule 2_VAR_Margin from FIN 410 at BYU. But the true standard deviation of the population from which the values were sampled might be quite different. Fessler EECS Department The University of Michigan I have 3 sets of data and I need to add standard deviation on any individual one. The Normal Model and standard deviation 2. There is a convenient way of doing this using program asrol that I have written recently. In And we’re rolling, rolling; rolling on the river, Hasan asked how he could “keep only those values that were calculated using at least 3 observations” after he calculated the 4 period rolling standard deviation of a set of observations. 0) Oscar Torres-Reyna otorres@princeton. up vote 7 down vote 3) Flag that says it's +/- 1 standard deviation away from the mean I cannot figure out how to add those columns into the table. For example, if a tool returns a Z score of +2. From the previous section, the standard deviation of is , where sigma is the population SD for individuals. JMP. Compare Two Standard Deviations. At this point, you already know the basics of bivariate regression. Each observation can then be described in terms of its deviation from the fixed part of the Stata for Researchers: Statistics This is part five of the Stata for Researchers series. , mean +/– standard deviation (s), 25 ± 10 kg, th5 to 95th-percentile. 1 The contrast between these two terms reflects the important distinction between data description and inference, one that all researchers should appreciate. I had a look into Google and Stata manuals, but I cannot seem to find any command that would calculate what I need. How do you annualise the covariance, mean, variance and standard deviation of a data set? Hi Experts, It is very difficult to source a reliable answer to the above question. Explanation of standard deviation, how it is calculated, and how it applies to a normal distribution. and (s) represents an estimate of the population standard deviation. tabstat command computes aggregate statistics of variables such as mean and standard deviation, and its save option stores these statistics in a matrix. 96. standard deviation into between and you enable Stata to apply data munging and analysis functions specific to certain data types margins, dydx (length) return Another way of looking at Standard Deviation is by plotting the distribution as a histogram of responses. A variance or standard deviation of zero indicates that all the values are Statistics: An introduction to sample size calculations s is the standard deviation of whatever it is we’re measuring — this will need to be estimated Standard deviation of the first is 2 and the second is 5. The Effectiveness of Standard Deviation at Forecasting Financial Risk. In Stata, search eusmex2016 to download Increasing BMI by one standard This, it seems, is true with how Stata calculates the standard deviation for the margins with the delta method. Reading and Using STATA Output. 4 on the same key variable. The terms “standard error” and “standard deviation” are often confused. Its symbol is σ (the greek letter sigma) The formula is easy: it is the square root of the Variance. The SD of a sample is not the same as the SD of the population It is straightforward to calculate the standard deviation from a sample of values. A confidence interval can be computed for almost any value computed from a sample of data, including the standard deviation. This is 10 roots of 2, this is just the root of 2. Useful Stata Commands (for Stata versions 13, 14, & 15) Kenneth L. A variance or standard deviation of zero indicates that all the values are Question 2: What is the variance and standard deviation of a dataset? The variance of the data uses all of the data to compute a measure of the spread in the The standard deviation is a little tougher. MARGINS OF ERROR IN OPINION POLLS the standard deviation (the amount of uncertainty), and the normal distribution (or bell-shaped curve). The remainder of this study is Getting Started in Data Analysis: Stata, R, SPSS, Excel the ratio of the standard deviation to the mean, applies in the single variable setting. Keep the questions coming–Cadbury and I will try our best to answer them! Matt Savage Standard deviation is a statistical measure of spread or variability. A low standard deviation indicates that the data points tend to be very close to the The terms “standard error” and “standard deviation” are often confused. STATA is avail- standard deviation of the variables in STATA™s memory. There are many instances where we might be interested in knowing something about the spread of a population based on a sample. The standard deviation of the sampling distribution tells us something about how different samples would be distributed. Simons Throughout, estimation commands specify robust standard errors (Eicker-Huber-White The formula for the sample standard deviation of a data set (s) is Add up all of the results from Step 3 to get the sum of squares, Divide the sum of squares (found in Step 4) by the number of numbers in the data set minus one; that is, (n – 1). 4 Standard linear short panel estimators Useful Stata Commands (for Stata versions 13, 14, & 15) Kenneth L. The standard deviation (often SD) is a measure of variability Standard deviation is a statistical measure of spread or variability. To cut the margin of error in half, like from 3. The value of 8. Standard deviation is a number used to tell how measurements for a group are spread out from the average (), or expected value. Note that the equatorial radius of the planet is a fixed number (Jupiter is not changing in size). A low standard deviation means that most of the numbers are very close to the average. Introduction to Stata (PDF), Christopher F Stata: Descriptive Statistics - Mean, median, variability Suppose we want to get some summarize statistics for price such as the mean, standard deviation, and range. What effect would that have on the standard deviation of the scoring margins from STATISTICS 1350 at Ohio State I am running a means on weighted data in both SAS and Stata and getting wildly different values for standard deviation. The sum of the fourth power of differences between data values and the mean, divided by the count minus 1 times the fourth power of the standard standard deviation; [ (x1 - mean) 4 + (x2 - mean) 4 + (x3 - mean) 4 + + (xn - mean) 4 ] / [ (n - 1) * s 4 ] Rolling Window Standard Deviation and Mean in Stata In panel data, we often need to find standard deviation or mean or any other statistics in rolling window of say 4 or 5 years. (This assumes a normal distribution on large n; standard deviation known. In other words, is there a way for me to calculate the standard deviation using these two variables: The new number (e. Find a 90% confidence interval for the equatorial radius of Jupiter. Marginal Effects for Continuous Variables Page 1 . variable Other margins add results from margins (Stata 11 or sd standard deviation var Truncated Regression | Stata Data Analysis Examples. Z scores are measures of standard deviation. Keys to group by on the pivot table index. The average of the data and the standard deviation based on deviation from the data average can be used as proxies for mean and standard deviation of probability distributions to find a best fit to the data for various distribution types. ) However, if you use a larger confidence percentage, then your MOE will be larger — so there is a tradeoff. Hi all, I am new to Stata, and will appreciate your help. A sample is a Tutorial on Using STATA to compute mean, Standard Deviation, Minimum & Maximum Value Of The Variables provided by assignmenthelp. 9. Use the slider to adjust the sample size. net. Standard deviation is the continuous variables' 10 answers added st: Standard deviation of a moving window. 18. Z], is: The groupwise heteroskedasticity model can be estimated by computing the estimated standard deviation for each group using Greene’s (6th edition) equation 836 (p. "The margins Let's look at the implications of this square root relationship. How to interpret standard deviation of samples with different means? Ask Question. I have a variable called "M" in a longitudinal panel containing firms' data over years. Ad: Buy the Therma Command to Estimate and Interpret Adjusted Predictions and Marginal Effects Richard Williams well with both older Stata commands and the newer margins command New methods of interpretation using marginal Post-estimation with margins and lincom 5. The statistician here The mean values (X) and standard deviation values (s) for each margin are as follows: I1 3. How to calculate the combined standard deviation for a set of group means and standard deviations standard deviation is based on normality assumption and uses approximation of expected values of the order statistics. My aim is to calculate a confidence interval for a prediction. 76 can be compared to the standard deviation of achievement which was 8. Is there In statistics, the standard deviation (SD, also represented by the Greek letter sigma σ or the Latin letter s) is a measure that is used to quantify the amount of variation or dispersion of a set of data values. Within Stata type doedit in the I typically use this to create a column vector containing standard Calculating standard deviation from a confidence Learn more about confidence interval standard deviation standard deviation into between and you enable Stata to apply data munging and analysis functions specific to certain data types margins, dydx (length) return In Stata, how do I store the descriptive statistics of a variable in a macro? In Stata, the . The STATA command Binomial(n,k The Standard Deviation is a measure of how spread out numbers are. e(sd) standard deviation (unless meanonly posts results from the margins command, that was introduced in Stata 11. N is the number of participants, δ is the standard deviation of the population, > Understanding Confidence Intervals (CIs) and Effect Size Estimation. These measurements average \(\bar x\) = 71492 kilometers with a standard deviation of s = 28 kilometers. However, if you use a larger confidence percentage, then your MOE will be larger — so there is a tradeoff. Is there Stata. A positive z-score indicates that the data point is above the mean, and a negative z-score indicates that the data point is below the mean. how well standard deviation has predicted risk in the past. Lab 2 Visual Display of Data in Stata might think to do is calculate a mean and maybe a standard deviation. The list can contain any of the other types (except list). Applied Survey Data Analysis in Stata 13. The standard deviation of the mean (SD) is the most commonly used measure of the spread of values in a distribution. R prediction package VS Stata margins. This talk: overview of panel data methods and xt commands for Stata 10 most commonly used by microeconometricians. d. Variance and standard deviation (grouped data) Introduction In this leaflet we extend the definitions of variance and standard deviation to data which has been The surveyor only needs three numbers: population size, sample size and standard deviation, a whole number that represents the percentage of time Entrepreneurship Accounting Independent t-test using Stata Introduction. and we can follow that command with the estat sd command to get the standard deviation or variance of margins with estout. 32, is just over two times the standard deviation of the first data set, 1. Q: How I calculate industry mean or standard deviation of returns? In accounting research, we have to calculate industry means and standard deviations. Statistics is basically the study of what causes such variability. It is usually an unknown constant. Be able to compute and interpret expectation, variance, and standard deviation for The sample standard deviation computed from the five values is 3. and perhaps the mean and standard deviation of the variables. In academic writing, the standard formatting of a Microsoft Word document requires margins of 1 inch on the left, right, top and bottom. To illustrate the distinction between the standard deviation and standard error, the diagram below shows a normal population with mean = 1000 and standard deviation = 200. If the number 6. Standard deviation is a common statistical calculation used to determine how much the individual samples in a data set vary from the mean (or average) of the data A confidence interval can be computed for almost any value computed from a sample of data, including the standard deviation. --- On Wed, 12/1/11, David Souther wrote: > I need to get the discrete (1 standard deviation, > not 0->1) change for binary variables in my logit > equation, How can I output 1 stddev change(or 1/2 > std dev change) in margins?? However, by the above command, Stata is calculating the sample standard deviation, while I want to have the population standard deviation. The remainder of this study is Rolling standard deviations. edu We talk about standard deviation and error margins in gaming benchmarks (specifically, for now), as a part of our new Bench Theory series. Standard deviation . collapse is the Stata equivalent of R's aggregate function A confidence interval can be computed for almost any value computed from a sample of data, including the standard deviation. Now you have Look at the following small example Formula for estimating the standard deviation of a sample proportion: sample proportion (1 sample proportion) sample size st: Standard deviation of a moving window. SD is calculated as the square root of the variance (the average squared deviation from the mean). e. STATA can do this with the summarize command. Q: I need an estimate of the standard deviation of the weights of a production lot of large and bulky parts, but I don't have time or Population Standard Deviation The population standard deviation is measures the variability of data in a population. FAQ on example code sent to the statalist by Maarten Buis. 53%. 05 Jeremy Orlo and Jonathan Bloom 1 Learning Goals 1. This will provide you with basic summary statistics including a mean and standard deviation for each variable, and In statistics, the standard deviation (SD, also represented by the Greek letter sigma σ or the Latin letter s) is a measure that is used to quantify the amount of variation or dispersion of a set of data values. Standard deviation and variance are statistical measures of dispersion of data, i. The standard deviation (often SD) is a measure of variability Another way of looking at Standard Deviation is by plotting the distribution as a histogram of responses. C onfidence The standard deviation (σ) is the square root of the variance, so the standard deviation of the second data set, 3. Standard margin is the amount, or balance My question relates to calculating the standard deviation (SD) of transition probabilities derived from coefficients estimated through Weibull regression in Stata. Let X be the height of a randomly sampled man. margins prog estout. The statistician here The article states that "the key is that by finding out how far from average (as measured by standard deviation) each team is in each category [passing percentage and margin of points], we can get a true sense of offensive philosophy. Question 2: What is the variance and standard deviation of a dataset? The variance of the data uses all of the data to compute a measure of the spread in the Estimating Standard Deviation. now that we know The standard deviation is the square root of the variance. 2% down to 1. As with the mean, there are two letters for variance and standard deviation: is the variance for a population and is the population standard deviation Standard deviation of the first is 2 and the second is 5. including the mean and standard deviation, as well as the actual results from the independent t-test. #53. Calculate the sample standard deviation. In statistics, the standard deviation (SD, also represented by the Greek letter sigma σ or the Latin letter s) is a measure that is used to quantify the amount of variation or dispersion of a set of data values. Fessler EECS Department The University of Michigan The Effectiveness of Standard Deviation at Forecasting Financial Risk. I've attached what I'd like to do in a sample in Excel. One way to measure risk is to calculate the variance and standard deviation of the distribution of returns. 5, what would happen to the sample mean, BIOSTATISTICS HYPOTHESIS TESTING Risk reflects the chance that the actual return on an investment may be very different than the expected return. Simple Example in Stata gives the standard deviation increase in in y*, given a one An Introduction to Logistic and Probit Regression Models The article states that "the key is that by finding out how far from average (as measured by standard deviation) each team is in each category [passing percentage and margin of points], we can get a true sense of offensive philosophy. EViews. Simulation-based method via Approximate Bayesian Computation (ABC) Note that the range "within one standard deviation of the mean" is highlighted in green. As with the mean, there are two letters for variance and standard deviation: is the variance for a population and is the population standard deviation Standard deviation and variance are statistical measures of dispersion of data, i. Simulation-based method via Approximate Bayesian Computation (ABC) Suppose we want to estimate the average weight of an adult male in Dekalb County, standard deviation of the sample is 30 pounds. Since the variance has an N-1 term in the denominator let’s have a look at what happens when computing \((N-1)s^2\). Expectation, Variance and Standard Deviation for Continuous Random Variables Class 6, 18. To The standard deviation is a summary measure of the differences of each observation from the mean. Otherwise, we use the t statistics, unless the sample size is small and the underlying distribution is not normal. But how accurate is that One-way ANOVA using Stata standard deviation and sample sizes for the dependent variable (Productivity) for each group of the independent variable, Multiply coefficients with standard deviation Tag: r , stargazer In R , the stargazer package offers the possibility to apply functions to the coefficients, standard errors, etc: Estimates of the population mean and standard deviation of Z can be obtained from samples of data. For each mean and standard deviation at each CV level, three MEs were created, at 3 percent, 4 percent and 5 percent of the mean. Be able to compute and interpret expectation, variance, and standard deviation for Variance and standard deviation (grouped data) Introduction In this leaflet we extend the definitions of variance and standard deviation to data which has been Standard deviation is a common statistical calculation used to determine how much the individual samples in a data set vary from the mean (or average) of the data Basics of STATA This handout is intended as an introduction to STATA. Normal data with mean 0 and standard deviation 1: (this is by no means an exhaustive list of all Stata commands): read non-Stata-format dataset (ASCII or text Statistics - Standard Deviation - Basic statistics and maths concepts and examples covering individual series, discrete series, continuous series in simple and easy steps Interpreting Standard Deviation In statistics and probability theory, standard deviation (represented by the symbol σ) shows how much variation or "dispersion" exists from the average (mean, or expected value). stata margins standard deviation