Comparing Two Population Means (Independent Samples): Apply It 1

  • Complete a two-sample [latex]t[/latex]-test for independent population means from hypotheses to conclusions

Hate Crime in California

A hate crime is defined as a criminal offense that is motivated, in whole or in part, by the offender’s bias(es) against a person based on race, ethnicity, ancestry, religion, sexual orientation, disability, gender, and gender identity. [1] In the year 2020, [latex]62\%[/latex] of victims were targeted because of the offenders’ bias toward race/ethnicity/ancestry, which continues to be the largest bias motivation category. Participating agencies reported [latex]5,227[/latex] race/ethnicity/ancestry-based incidents in 2020, a [latex]32\%[/latex] increase from 2019. Anti-Black or African American hate crimes continue to be the largest bias incident victim category, with [latex]2,871[/latex] incidents in 2020, a [latex]49\%[/latex] increase since 2019. Additionally, there were [latex]279[/latex] anti-Asian incidents reported in 2020, a [latex]77\%[/latex] increase since 2019. The other largest categories of hate crimes include anti-Hispanic or Latino incidents, with [latex]517[/latex], and anti-White incidents, with [latex]869[/latex] in total.

Suppose we wanted to study the increase in hate crime from 2019 to 2020, specifically in the state of California.

Previously, you have conducted a one-sample [latex]t[/latex]-test (a hypothesis test about a population mean). We can apply the same steps to analyze and test a hypothesis about the difference in means for two independent populations. A hypothesis test for comparing two population means is often referred to as a two-sample [latex]t[/latex]-test.

Note: Previously, we have verified that the assumptions for a two-sample [latex]t[/latex]-test were met for the Hate Crime data set for the state of California. We know that the two samples were independent, representative of the populations of interest, and large.


  1. https://www.justice.gov/crs/highlights/2020-hate-crimes-statistics