Exam 19: Statistics in Psychological Research

Dorothea conducts a survey to find out how many national parks people have visited in the past two years. She polls twenty people and finds that ten people have visited no national parks; five people have visited one national park; four people have visited two national parks; and one person has visited twenty national parks. Which measure of central tendency should Dorothea use to provide the most accurate picture of her data?

Professor Goranson studies the relation between adolescents' self-esteem and the number of close friends they report having. After completing her statistical analyses, Professor Goranson finds that as the number of close friendships increased, adolescents' self-esteem rose moderately. Which correlation coefficient did she likely obtain?

Richard Simmons wants to know whether his original weight-loss system (Simmons I)is as effective as his new weight-loss system (Simmons II). His results indicate that people on Simmons I lose an average of 28.5 pounds in six months and people on Simmons II lose an average of 30.1 pounds in six months. What type of statistics should Richard use to see if the Simmons II system is really better than the Simmons I system?

While conducting statistical analysis, Gordon forgets how to calculate degrees of freedom. All he knows is that Group 1 has twenty-three subjects and Group 2 has twenty-seven subjects. How many degrees of freedom should Gordon use for his analysis?

Sumon is conducting an experiment. The six experimental groups receive three different dosage levels of a drug either in the morning or in the evening. Sumon is trying to investigate the interaction between dosage level and the time of day of the dose. Sumon will most likely choose to analyze his data with a(n)____.

Edhilvia is studying the relationship between smoking and number of visits to the doctor. After giving a survey to 1,000 people, she finds that the more people smoked, the more times they visited the doctor every year. From these results, Edhilvia can logically conclude that ____.

Dr. Banguna is conducting an experiment to discover the effects of money payments (independent variable)on work performance (dependent variable). Dr. Banguna's null hypothesis would state ____.

You are conducting a survey of international students studying at your university. Several of the questions on the survey try to determine how much exposure to American culture the student had before coming to the United States. You suspect that the more exposure the student had before arriving here, the fewer problems of adjustment he or she will report. You are looking for a(n)____.

If an IQ test is constructed to have a mean of 100 and a standard deviation of 16, approximately what percentage of scores falls between 84 and 116?

In Diti's study, employees who listened to rap music produced an average of 5.71 units and employees who listened to polka music produced an average of 2.71 units. To see if the difference between these means is statistically significant, Diti should ____.

Anqi is creating a picture-like graphic for her research paper. This graphic will be used to summarize and describe data she collected. Anqi is creating a ____.

As a researcher, you are interested in how the scores in your data set are dispersed. Specifically, you want to know the average difference between each score and the mean. You would find out this information by looking at the ____.

Hui-Hui has just received her scores on the Scholastic Achievement Test (SAT)and learns that her score was at the 84th percentile. Hui-Hui's score represents a standard score of ____.

What information is necessary to calculate the degrees of freedom for a t test?

Which of the following is a characteristic of a normal distribution?

Jack is a handsome and extremely charming fellow who is currently dating four women, but now must choose one. Alas, Jack is somewhat shallow and eccentric. He has decided to choose the woman whose median cost on a date is the lowest. The dollar amounts of the five dates with each woman are given below.  Which of the women should Jack choose?

The most basic use of histograms is to ____.

Professor Jenrick has just completed an experiment in which he observed how many times a particular color was selected when 100 people were each given a choice of red, green, or blue. He represents the data graphically by constructing three boxes (labeled Red, Green, and Blue)whose heights are proportional to the number of times each color was chosen. Professor Jenrick has constructed a ____ of the data.

In Dr. Dalbey's study, women missed an average of three work days a year because of colds, and men missed an average of five work days because of colds. To see if the difference between these means is statistically significant, Dr. Dalbey should ____.

Francesca is at a casino watching a game involving dice. She determines that one of the dice is loaded, causing it to turn up "3" more often than would be expected by chance. To know for certain if this was true, Francesca would have to conduct a study to determine if her findings have statistical ____.