Jasmine wants to see if indoor cats differ from outdoor cats in time spent scratching posts per day. She records 12 indoor and 12 outdoor cats. She has no prediction about which group will scratch more.

Which assumption is required for this independent samples t-test?

Question

Jasmine wants to see if indoor cats differ from outdoor cats in time spent scratching posts per day. She records 12 indoor and 12 outdoor cats. She has no prediction about which group will scratch more.

Which assumption is required for this independent samples t-test?

BlackTom AI · Accepted Answer

When evaluating the assumptions of an independent samples t-test, several key conditions must be considered. 
Option 1: "The data must be normally distributed and have heterogeneity of variance". Here, the notion of heterogeneity of variance (also called unequal variances) is not the standard assumption for the basic independent t-test; in fact, equal variances are assumed (or at least tested for) unless using a variant that adjusts for unequal variances. Thus this option misstates the variance assumption.
Option 2: "The data must be normally distributed and have homogeneity of variance". This aligns with the classic prerequisites: each group should come from a normally distributed population and the two groups should have equal (homogeneous) variances. These conditions ensure the t-test statistic follows the t-distribution under the null hypothesis and that the standard error is appropriately estimated. This option correctly captures the standard assumptions.
Option 3: "The two groups must have equal means". Equating means is not an assumption; it is precisely what the test evaluates for evidence against the null hypothesis. The means are allowed to differ if there is a genuine effect; assuming equality of means would defeat the purpose of the test.
Option 4: "The two groups must have unequal means". Similarly, requiring unequal means is not a methodological assumption for conducting the t-test. The test is designed to detect whether means are different, not to require that they are different. This option confuses the goal of hypothesis testing with an assumption about the true population parameters.
In summary, the only option that correctly states the standard prerequisites for an independent samples t-test is the one describing normal distribution within groups and equal variances between groups, while the other options misrepresent variance requirements or the purpose of the test.

Jasmine wants to see if indoor cats differ from outdoor cats in time spent scratching posts per day. She records 12 indoor and 12 outdoor cats. She has no prediction about which group will scratch more. Which assumption is required for this independent samples t-test?单项选择题

类似问题

Which of the following assumptions have been made in carrying out the analysis in Question 3? (Tick as many as apply.)

Which of the following is not a simple condition for inference about a population mean?

Which is NOT an assumption underlying t-tests?

In R, before running a t-test, you are required to:

As of 2022, the world's human population was approximately:

What is the effect on the financial statements when a company fails to adjust the unearned revenue account for revenues earned at year-end?

Which of the following correctly describes the effects of initially recording prepaid insurance expense when cash is paid to purchase an insurance policy?

更多留学生实用工具

智能学习助手

风格化写作助手

论文查重助手

文献引用助手

课堂转译助手

课堂笔记助手

Quiz搜索助手

学校历年真题

智能刷题助手

智能匹配练习

希望你的学习变得更简单