Exam 1: An Introduction to Statistics and Research Design

An assessment that produces the same results each time it is administered is said to be _____, even though it may not be measuring what we are interested in studying.

A population is generally defined as:

Interesting things can be learned from examining scores that do not fit with the overall pattern of data.This is known as:

Confounding variables are connected to the independent variable such that we cannot know which variable causes the effect we observe.

Which types of variables are considered scale variables by statistical computing packages such as SPSS?

A researcher is interested in the effectiveness of natural remedies for allergies.The researcher randomly assigns to 30 allergy sufferers a treatment of herbal tea, homeopathic doses of the allergens, or a traditional antihistamine.What type of research design has the researcher employed?

Maria wants to know if identical twins raised in different environments have different IQ scores.What type of research design is NOT available for Maria to use because she cannot randomly assign the participants?

College students at 20 campuses around the country were polled to find out how many students own MP3 players.This small representative group of students is called a:

Outliers are typically nuisances to a study and should immediately be excluded without further analysis.

The measurement of the performance of runners in a race based on their finishing places is a(n) _____ variable.The measurement of the performance of runners in a race based on their times to complete the race is a(n) _____ variable.

An elementary school teacher is interested in the relation between sugar consumption and activity level in preschool children.The teacher gives 30 preschool children from Preppy Preschool Playland 0 milligrams, 20 milligrams, or 50 milligrams of sucrose (sugar) in a breakfast drink.She then observes their behavior for 30 minutes during their morning outdoor play period and codes their activity level.In this example, the sample is:

In 2000, Bartels and Zeki performed a study in which they hypothesized that there may be special pathways in the brain that support the feeling of romantic love.To test their hypothesis they recruited volunteers who reported themselves to be "truly, deeply, and madly in love." They then used brain imaging methods to determine which areas of the volunteers' brains were active when looking at pictures of their loved one.How did these researchers operationally define romantic love?

A weight-management researcher was interested in whether the size of breakfast could deter overall food consumption throughout the rest of the day.He creates two breakfast groups, a 350-calorie breakfast and a 750-calorie breakfast, assigns six participants to each group, and tracks their total calories eaten in one day.Because of the detailed attention needed to accurately interview participants about their eating, he works with the high-calorie group and has his assistant interview the low-calorie group.What is the confounding variable in this study?

Unnithan, Houser, and Fernhall (2006) were interested in whether playing the game Dance Dance Revolution (DDR) met the American College of Sports Medicine recommendations for exercise to improve cardiovascular health.Twenty-two adolescents, 10 of whom were classified as overweight and 12 of whom were not overweight, played DDR for 12 minutes.During the 12 minutes, the researchers measured each participant's heart rate.On average, the researchers found no difference between the heart rates of the two groups.Both groups' heart rates were above the minimum recommended for cardiovascular exercise.What is the population in this study?

Controlling for _____ variables permits researchers to make statements about cause-effect relationships between variables.

Reading times are collected for bilingual participants, comparing their reading speed across their two languages.What type of research design would MOST likely be used in this study?

Wendy is a weight-loss group leader.To get a better idea of how to help those she will be working with to achieve their weight-loss goals, she wishes to know the average weight-loss goal of the individuals in her group.What kind of statistic should Wendy use?

Prof.Martin was interested in which of two popular statistics textbooks (Statistics: It Will Change Your Life and Statistics: Bigger, Better, Stronger) was better for students.Prof.Martin compared the two texts by assigning one text to a section of statistics taught by Prof.Miller from 10 to 11 a.m.on Monday, Wednesday, and Friday, and the other text to a section of statistics taught by Prof.Mervin from 7 to 10 p.m.on Wednesday evenings.At the end of the term, all students took the same comprehensive test.Students to whom Statistics: Bigger, Better, Stronger was assigned performed better on the test than did students to whom Statistics: It Will Change Your Life was assigned.Therefore, Prof.Martin concluded that the former textbook was the better one.What was the independent variable in this study?

A person's grade point average on a scale from 0 to 4.0 is a(n) _____ variable.

A weight-management researcher was interested in whether the size of breakfast could deter overall food consumption throughout the rest of the day.He creates two breakfast groups, a 350-calorie breakfast and a 750-calorie breakfast, assigns six participants to each group, and tracks their total calories eaten in one day.Because of the detailed attention needed to accurately interview participants about their eating, he works with the high-calorie group and has his assistant interview the low-calorie group.How many levels does the independent variable have in this study?