## How do you test if a coefficient is statistically significant in Stata?

STATA automatically takes into account the number of degrees of freedom and tells us at what level our coefficient is significant. If it is significant at the 95% level, then we have P < 0.05. If it is significant at the 0.01 level, then P < 0.01.

**How do you test for two independent samples?**

The test statistic for a two-sample independent t-test is calculated by taking the difference in the two sample means and dividing by either the pooled or unpooled estimated standard error. The estimated standard error is an aggregate measure of the amount of variation in both groups.

### Can you compare two regression models?

When comparing regression models that use the same dependent variable and the same estimation period, the standard error of the regression goes down as adjusted R-squared goes up.

**Can dummy variables be statistically significant?**

Since both dummy variables were not statistically significant, we could drop marital status as a predictor from the model because it doesn’t appear to add any predictive value for income.

## What is an example of a two-sample t-test?

The two-sample t-test is one of the most commonly used hypothesis tests in Six Sigma work. It is applied to compare whether the average difference between two groups is really significant or if it is due instead to random chance….Making Sense of the Two-Sample T-Test.

Table 1: Pizza Company A Versus Pizza Company B Sample | |
---|---|

A | B |

24.2 | 16.9 |

15.4 | 18.5 |

21.4 | 17.3 |

**How do you know if two samples are statistically different?**

A t-test is a type of inferential statistic used to determine if there is a significant difference between the means of two groups, which may be related in certain features. The t-test is one of many tests used for the purpose of hypothesis testing in statistics. Calculating a t-test requires three key data values.

### Does the ttest function in Stata work with different regression coefficients?

I know the ttest function in stata but it does not work in case the coefficients are coming from different regressions (as far as I know). In fact, I run twice the same regression but with different subsamples.

**What is the test statistic of the two sample t-test?**

t: The test statistic of the two-sample t-test. degrees of freedom: The degrees of freedom to be used for the test, calculated as n-2 = 24-2 = 22. The p-values for three different two sample t-tests are displayed at the bottom of the results.

## How do you test the equality of regression coefficients?

How do you test the equality of regression coefficients that are generated from two different regressions, estimated on two different samples? You must set up your data and regression model so that one model is nested in a more general model. For example, suppose you have two regressions,

**How do I run a t-test on two sample groups?**

Along the top menu bar, go to Statistics > Summaries, tables, and tests > Classical tests of hypotheses > t test (mean-comparison test). Choose Two-sample using groups.