Exam 7: Testing Differences Between Means

The question below refers to the following: The administration at a university is interested in studying if any relationship exists between satisfaction at the school and whether the student is a freshman or a senior. The school randomly surveys 10 freshmen and 10 seniors and asks them to rate how satisfied they are at the school on a scale of 1-10, where 10 is extremely satisfied and 1 is extremely dissatisfied. Here is the collected data: Calculate t.

The standard error of the difference between means:

Which of the following does NOT exemplify a research hypothesis:

The question below refers to the following data: A social researcher wants to test the hypothesis that college students who drink alcohol while text messaging create a different number of keystrokes than those who do not drink while they text. The social researcher studies 50 drinking texters and 50 non-drinking texters. The average number of keystrokes for the drinking texters was 142 with a standard deviation of 7.45. The average number of keystrokes for the non-drinking texters was 134 with a standard deviation of 6.81. What are your conclusions about the null hypothesis?

The question below refers to the following data: A social researcher wants to test the hypothesis that college students who drink alcohol while text messaging create a different number of keystrokes than those who do not drink while they text. The social researcher studies 50 drinking texters and 50 non-drinking texters. The average number of keystrokes for the drinking texters was 142 with a standard deviation of 7.45. The average number of keystrokes for the non-drinking texters was 134 with a standard deviation of 6.81. Are your results significant, and if so, at what level?

The symbols for a Type 1 error and Type 2 error are respectively

Democrats and Republicans were surveyed on their support of healthcare reform using a standardized measure (high scores representing greater support of healthcare reform). Using the data provided, calculate t.

If our obtained t-value is greater than our critical t-value, we believe that the null hypothesis is __________.

The null hypothesis in a two-tailed, independent t-test of means would be:

When we test hypotheses of differences between means, we:

English proficiency scores have been collected from 46 students before and after completing an English as a Second Language course. The degrees of freedom for our t-test are __________.

If we reject the null hypothesis when in reality the null hypothesis is true, we have:

The question below refers to the following: The administration at a university is interested in studying if any relationship exists between satisfaction at the school and whether the student is a freshman or a senior. The school randomly surveys 10 freshmen and 10 seniors and asks them to rate how satisfied they are at the school on a scale of 1-10, where 10 is extremely satisfied and 1 is extremely dissatisfied. Here is the collected data: What are the degrees of freedom?

The question below refers to the following data: A social researcher wants to test the hypothesis that college students who drink alcohol while text messaging create a different number of keystrokes than those who do not drink while they text. The social researcher studies 50 drinking texters and 50 non-drinking texters. The average number of keystrokes for the drinking texters was 142 with a standard deviation of 7.45. The average number of keystrokes for the non-drinking texters was 134 with a standard deviation of 6.81. What is the research hypothesis? (Pay attention to the scenario.)

The question below refers to the following data: A social researcher wants to test the hypothesis that college students who drink alcohol while text messaging create a different number of keystrokes than those who do not drink while they text. The social researcher studies 50 drinking texters and 50 non-drinking texters. The average number of keystrokes for the drinking texters was 142 with a standard deviation of 7.45. The average number of keystrokes for the non-drinking texters was 134 with a standard deviation of 6.81. Calculate t.

We predetermine our level of _____ for a hypothesis test on the basis of which type of error is more costly.

The t-test can be used for testing the same sample measured twice as well as for two independent samples.

If we retain a null hypothesis that is in fact false:

Compared to the .05 level of significance, the .01 level of significance means:

Some researchers contend that anxiety is detrimental to performance, while other researchers contend that anxiety actually enhances performance. To help shed light on this question, Dr. Patterson has her participants work on crossword puzzles both before and after being exposed to an anxiety-inducing stimulus. The scores on an anxiety rating scale from her 4 participants are presented below. Using α = .05, test the null hypothesis that the two groups do not differ.