Exam 9: Introduction to Simple Experiments

RESEARCH STUDY 9.3 Dr. Phillips is a cognitive-developmental psychologist who studies how children learn mathematical principles. His current interest is in studying how children learn multiplication. He recruits 54 second graders who have not yet learned how to multiply numbers to participate in his study. He is curious as to whether different teaching styles lead to better mastery of the subject. One condition (A) involves having students read a chapter on multiplication from their textbook. One condition (B) involves having students watch a video of cartoon characters explaining multiplication. One condition (C) involves having students being taught multiplication from a teacher. One condition (D) involves having students being taught multiplication by a fourth grader. In all conditions, participants spend 30 minutes learning the fundamentals of multiplication and are then given the same 15-question multiplication test. The number of questions answered correctly is recorded. The data are below. -Refer to Research Study 9.3 above to answer the following question. Explain why Dr.Phillips cannot conduct a within-groups design.

RESEARCH STUDY 9.3 Dr. Phillips is a cognitive-developmental psychologist who studies how children learn mathematical principles. His current interest is in studying how children learn multiplication. He recruits 54 second graders who have not yet learned how to multiply numbers to participate in his study. He is curious as to whether different teaching styles lead to better mastery of the subject. One condition (A) involves having students read a chapter on multiplication from their textbook. One condition (B) involves having students watch a video of cartoon characters explaining multiplication. One condition (C) involves having students being taught multiplication from a teacher. One condition (D) involves having students being taught multiplication by a fourth grader. In all conditions, participants spend 30 minutes learning the fundamentals of multiplication and are then given the same 15-question multiplication test. The number of questions answered correctly is recorded. The data are below. -Refer to Research Study 9.3 above to answer the following question. Name two ways that Dr.Phillips could avoid selection threat when he is assigning participants to conditions and explain why each of these methods avoids selection threat.

All of the following are advantages of within-groups designs EXCEPT:

RESEARCH STUDY 9.2 Dr. Acitelli studies sleep and sleep disorders. She is curious as to whether falling asleep in front of a television set causes people to fall asleep more slowly than falling asleep regularly. She recruits a sample of 60 middle-aged women from a local church who reported no history of sleep problems. She creates three conditions. All participants come to the sleep lab for three nights in a row and experience all three conditions. In the first condition (A), participants fall asleep in front of a television that is off. In the second condition (B), participants fall asleep in front of a television that is turned on to the same 24-hour news channel. In the third condition (C), participants fall asleep in front of a television that is turned on to the same 24-hour news channel but is muted. With the use of an electroencephalograph (EEG), the researcher measures how long it takes participants to fall asleep. -Refer to Research Study 9.2 above to answer the following question. Which of the following designs is Dr.Acitelli using?

RESEARCH STUDY 9.1 Dr. Lonsbary is a cognitive psychologist who is curious about how mood affects memory. She recruited 60 high school students and divided them into three groups. One group (A) listened to a 5-minute piece of music intended to make them feel happy (a song entitled "Don't Worry, Be Happy"). One group (B) listened to a 5-minute piece of music intended to make them feel sad (a song entitled "Alone Again"). One group (C) listened to no music and instead was asked to sit quietly for 5 minutes (thought to make them feel neutral). When a participant would come to her laboratory, she would greet the participant and then ask him or her to draw a card. If the participant drew a 1, 2, or 3, he or she was assigned to Group A. If the participant drew a 4, 5, or 6, he or she was assigned to Group B. If a participant drew a 7, 8, or 9, he or she was assigned to Group C. The participants were then given a CD to listen to based on their group assignment. The CD contained the song selection or 5 minutes of silence. There were no identifying marks on the CD indicating what was contained on the disc. They were then escorted into a different room, where they were greeted by a research assistant who conducted the experiment. The research assistant sat the participants in front of a computer screen and told them that a list of 25 words would be displayed on the screen. They were instructed to put the CD in the computer, put on the headphones, and listen to the CD while trying to memorize the list of words. When 5 minutes had passed, the screen displayed a question asking them whether they felt happy, sad, or neutral. After the participant responded, a new screen was displayed asking them to type in all the words they could remember from the list of 25 words. All participants were given 3 minutes to type the words they remembered. In addition, all participants were given the same list of 25 words to remember. Afterward, the participant was thanked and dismissed. In response to the mood question, a majority of Group A participants said they were happy, a majority of Group B participants said they were sad, and a majority of Group C participants said they were neutral in their mood. Dr. Lonsbary found the following results in response to the number of words remembered. -Refer to Research Study 9.1 above to answer the following question. Which of the following is an independent variable in Dr.Lonsbary's study?

RESEARCH STUDY 9.2 Dr. Acitelli studies sleep and sleep disorders. She is curious as to whether falling asleep in front of a television set causes people to fall asleep more slowly than falling asleep regularly. She recruits a sample of 60 middle-aged women from a local church who reported no history of sleep problems. She creates three conditions. All participants come to the sleep lab for three nights in a row and experience all three conditions. In the first condition (A), participants fall asleep in front of a television that is off. In the second condition (B), participants fall asleep in front of a television that is turned on to the same 24-hour news channel. In the third condition (C), participants fall asleep in front of a television that is turned on to the same 24-hour news channel but is muted. With the use of an electroencephalograph (EEG), the researcher measures how long it takes participants to fall asleep. -Refer to Research Study 9.2 above to answer the following question. Given that Dr.Acitelli's participants have agreed to participate for all three nights,which type of counterbalancing should she use?

RESEARCH STUDY 9.3 Dr. Phillips is a cognitive-developmental psychologist who studies how children learn mathematical principles. His current interest is in studying how children learn multiplication. He recruits 54 second graders who have not yet learned how to multiply numbers to participate in his study. He is curious as to whether different teaching styles lead to better mastery of the subject. One condition (A) involves having students read a chapter on multiplication from their textbook. One condition (B) involves having students watch a video of cartoon characters explaining multiplication. One condition (C) involves having students being taught multiplication from a teacher. One condition (D) involves having students being taught multiplication by a fourth grader. In all conditions, participants spend 30 minutes learning the fundamentals of multiplication and are then given the same 15-question multiplication test. The number of questions answered correctly is recorded. The data are below. -Refer to Research Study 9.3 above to answer the following question. Identify the independent variable(s),dependent variable(s),and a control variable in Dr.Phillips's study.

RESEARCH STUDY 9.1 Dr. Lonsbary is a cognitive psychologist who is curious about how mood affects memory. She recruited 60 high school students and divided them into three groups. One group (A) listened to a 5-minute piece of music intended to make them feel happy (a song entitled "Don't Worry, Be Happy"). One group (B) listened to a 5-minute piece of music intended to make them feel sad (a song entitled "Alone Again"). One group (C) listened to no music and instead was asked to sit quietly for 5 minutes (thought to make them feel neutral). When a participant would come to her laboratory, she would greet the participant and then ask him or her to draw a card. If the participant drew a 1, 2, or 3, he or she was assigned to Group A. If the participant drew a 4, 5, or 6, he or she was assigned to Group B. If a participant drew a 7, 8, or 9, he or she was assigned to Group C. The participants were then given a CD to listen to based on their group assignment. The CD contained the song selection or 5 minutes of silence. There were no identifying marks on the CD indicating what was contained on the disc. They were then escorted into a different room, where they were greeted by a research assistant who conducted the experiment. The research assistant sat the participants in front of a computer screen and told them that a list of 25 words would be displayed on the screen. They were instructed to put the CD in the computer, put on the headphones, and listen to the CD while trying to memorize the list of words. When 5 minutes had passed, the screen displayed a question asking them whether they felt happy, sad, or neutral. After the participant responded, a new screen was displayed asking them to type in all the words they could remember from the list of 25 words. All participants were given 3 minutes to type the words they remembered. In addition, all participants were given the same list of 25 words to remember. Afterward, the participant was thanked and dismissed. In response to the mood question, a majority of Group A participants said they were happy, a majority of Group B participants said they were sad, and a majority of Group C participants said they were neutral in their mood. Dr. Lonsbary found the following results in response to the number of words remembered. -Refer to Research Study 9.1 above to answer the following question. Dr.Lonsbary's decision to randomly assign participants to the three groups was done to avoid which of the following?

RESEARCH STUDY 9.1 Dr. Lonsbary is a cognitive psychologist who is curious about how mood affects memory. She recruited 60 high school students and divided them into three groups. One group (A) listened to a 5-minute piece of music intended to make them feel happy (a song entitled "Don't Worry, Be Happy"). One group (B) listened to a 5-minute piece of music intended to make them feel sad (a song entitled "Alone Again"). One group (C) listened to no music and instead was asked to sit quietly for 5 minutes (thought to make them feel neutral). When a participant would come to her laboratory, she would greet the participant and then ask him or her to draw a card. If the participant drew a 1, 2, or 3, he or she was assigned to Group A. If the participant drew a 4, 5, or 6, he or she was assigned to Group B. If a participant drew a 7, 8, or 9, he or she was assigned to Group C. The participants were then given a CD to listen to based on their group assignment. The CD contained the song selection or 5 minutes of silence. There were no identifying marks on the CD indicating what was contained on the disc. They were then escorted into a different room, where they were greeted by a research assistant who conducted the experiment. The research assistant sat the participants in front of a computer screen and told them that a list of 25 words would be displayed on the screen. They were instructed to put the CD in the computer, put on the headphones, and listen to the CD while trying to memorize the list of words. When 5 minutes had passed, the screen displayed a question asking them whether they felt happy, sad, or neutral. After the participant responded, a new screen was displayed asking them to type in all the words they could remember from the list of 25 words. All participants were given 3 minutes to type the words they remembered. In addition, all participants were given the same list of 25 words to remember. Afterward, the participant was thanked and dismissed. In response to the mood question, a majority of Group A participants said they were happy, a majority of Group B participants said they were sad, and a majority of Group C participants said they were neutral in their mood. Dr. Lonsbary found the following results in response to the number of words remembered. -Refer to Research Study 9.1 above to answer the following question. How many conditions/levels of the independent variable were in Dr.Lonsbary's study?

An independent-groups design is also known as a _____________.

When conducting an experiment,what is provided by the independent variable?

Name three advantages of within-groups designs.

RESEARCH STUDY 9.2 Dr. Acitelli studies sleep and sleep disorders. She is curious as to whether falling asleep in front of a television set causes people to fall asleep more slowly than falling asleep regularly. She recruits a sample of 60 middle-aged women from a local church who reported no history of sleep problems. She creates three conditions. All participants come to the sleep lab for three nights in a row and experience all three conditions. In the first condition (A), participants fall asleep in front of a television that is off. In the second condition (B), participants fall asleep in front of a television that is turned on to the same 24-hour news channel. In the third condition (C), participants fall asleep in front of a television that is turned on to the same 24-hour news channel but is muted. With the use of an electroencephalograph (EEG), the researcher measures how long it takes participants to fall asleep. -Refer to Research Study 9.2 above to answer the following question. Dr.Acitelli was concerned that asking participants how long it took them to fall asleep would lead them to suspect that was the purpose of the study.Her decision to measure how long it took participants to go to sleep using the EEG instead of self-report was meant to decrease which of the following?

For which of the following reasons might a researcher choose a pretest/posttest design?

RESEARCH STUDY 9.1 Dr. Lonsbary is a cognitive psychologist who is curious about how mood affects memory. She recruited 60 high school students and divided them into three groups. One group (A) listened to a 5-minute piece of music intended to make them feel happy (a song entitled "Don't Worry, Be Happy"). One group (B) listened to a 5-minute piece of music intended to make them feel sad (a song entitled "Alone Again"). One group (C) listened to no music and instead was asked to sit quietly for 5 minutes (thought to make them feel neutral). When a participant would come to her laboratory, she would greet the participant and then ask him or her to draw a card. If the participant drew a 1, 2, or 3, he or she was assigned to Group A. If the participant drew a 4, 5, or 6, he or she was assigned to Group B. If a participant drew a 7, 8, or 9, he or she was assigned to Group C. The participants were then given a CD to listen to based on their group assignment. The CD contained the song selection or 5 minutes of silence. There were no identifying marks on the CD indicating what was contained on the disc. They were then escorted into a different room, where they were greeted by a research assistant who conducted the experiment. The research assistant sat the participants in front of a computer screen and told them that a list of 25 words would be displayed on the screen. They were instructed to put the CD in the computer, put on the headphones, and listen to the CD while trying to memorize the list of words. When 5 minutes had passed, the screen displayed a question asking them whether they felt happy, sad, or neutral. After the participant responded, a new screen was displayed asking them to type in all the words they could remember from the list of 25 words. All participants were given 3 minutes to type the words they remembered. In addition, all participants were given the same list of 25 words to remember. Afterward, the participant was thanked and dismissed. In response to the mood question, a majority of Group A participants said they were happy, a majority of Group B participants said they were sad, and a majority of Group C participants said they were neutral in their mood. Dr. Lonsbary found the following results in response to the number of words remembered. -Refer to Research Study 9.1 above to answer the following question. Which of the following should Dr.Lonsbary conclude from her study?

What is the difference between a posttest-only design and a pretest/posttest design? Provide both a benefit and a cost of using a pretest/posttest design.

RESEARCH STUDY 9.1 Dr. Lonsbary is a cognitive psychologist who is curious about how mood affects memory. She recruited 60 high school students and divided them into three groups. One group (A) listened to a 5-minute piece of music intended to make them feel happy (a song entitled "Don't Worry, Be Happy"). One group (B) listened to a 5-minute piece of music intended to make them feel sad (a song entitled "Alone Again"). One group (C) listened to no music and instead was asked to sit quietly for 5 minutes (thought to make them feel neutral). When a participant would come to her laboratory, she would greet the participant and then ask him or her to draw a card. If the participant drew a 1, 2, or 3, he or she was assigned to Group A. If the participant drew a 4, 5, or 6, he or she was assigned to Group B. If a participant drew a 7, 8, or 9, he or she was assigned to Group C. The participants were then given a CD to listen to based on their group assignment. The CD contained the song selection or 5 minutes of silence. There were no identifying marks on the CD indicating what was contained on the disc. They were then escorted into a different room, where they were greeted by a research assistant who conducted the experiment. The research assistant sat the participants in front of a computer screen and told them that a list of 25 words would be displayed on the screen. They were instructed to put the CD in the computer, put on the headphones, and listen to the CD while trying to memorize the list of words. When 5 minutes had passed, the screen displayed a question asking them whether they felt happy, sad, or neutral. After the participant responded, a new screen was displayed asking them to type in all the words they could remember from the list of 25 words. All participants were given 3 minutes to type the words they remembered. In addition, all participants were given the same list of 25 words to remember. Afterward, the participant was thanked and dismissed. In response to the mood question, a majority of Group A participants said they were happy, a majority of Group B participants said they were sad, and a majority of Group C participants said they were neutral in their mood. Dr. Lonsbary found the following results in response to the number of words remembered. -Refer to Research Study 9.1 above to answer the following question. Which of the following is a dependent variable in Dr.Lonsbary's study?

Which of the following is true of selection effects?

RESEARCH STUDY 9.1 Dr. Lonsbary is a cognitive psychologist who is curious about how mood affects memory. She recruited 60 high school students and divided them into three groups. One group (A) listened to a 5-minute piece of music intended to make them feel happy (a song entitled "Don't Worry, Be Happy"). One group (B) listened to a 5-minute piece of music intended to make them feel sad (a song entitled "Alone Again"). One group (C) listened to no music and instead was asked to sit quietly for 5 minutes (thought to make them feel neutral). When a participant would come to her laboratory, she would greet the participant and then ask him or her to draw a card. If the participant drew a 1, 2, or 3, he or she was assigned to Group A. If the participant drew a 4, 5, or 6, he or she was assigned to Group B. If a participant drew a 7, 8, or 9, he or she was assigned to Group C. The participants were then given a CD to listen to based on their group assignment. The CD contained the song selection or 5 minutes of silence. There were no identifying marks on the CD indicating what was contained on the disc. They were then escorted into a different room, where they were greeted by a research assistant who conducted the experiment. The research assistant sat the participants in front of a computer screen and told them that a list of 25 words would be displayed on the screen. They were instructed to put the CD in the computer, put on the headphones, and listen to the CD while trying to memorize the list of words. When 5 minutes had passed, the screen displayed a question asking them whether they felt happy, sad, or neutral. After the participant responded, a new screen was displayed asking them to type in all the words they could remember from the list of 25 words. All participants were given 3 minutes to type the words they remembered. In addition, all participants were given the same list of 25 words to remember. Afterward, the participant was thanked and dismissed. In response to the mood question, a majority of Group A participants said they were happy, a majority of Group B participants said they were sad, and a majority of Group C participants said they were neutral in their mood. Dr. Lonsbary found the following results in response to the number of words remembered. -Refer to Research Study 9.1 above to answer the following question. What type of design did Dr.Lonsbary use in her study?

Name three disadvantages of within-groups designs.