Stat Psych Test 1

What does a ratio scale variable have that an interval scale variable does not?

An absolute zero

If I want to study a construct like anxiety, I cannot simply measure "anxiety" directly. What do I need to use instead, which includes behaviors that would be observable and indicative of anxiety?

An operational definition

In my experiment, I am studying whether my new drug improves concentration. One group receives the drug and the other receives a placebo. Which of the following is NOT a way that I could establish control in my experiment?

Assign older students to the treatment group and younger students to the placebo

On the first day of class, a professor records every student's favorite ice cream to create a frequency distribution graph? Which graph is the most appropriate?

Bargraph

A researcher wishes to study drinking behavior among college students in the U.S. Ten schools and 100 students from each of the 10 schools are randomly selected to fill out a survey. What is the population?

College students in the US Ten Schools

What does a Z=score of -1.00 tell you about a score

It is 1 standard deviation below the mean

In a study about student health and wellbeing, participants are divided into two different nutrition groups. Half eat lots of fruits and vegetables, whereas the others eat chocolate and potato chips. At the end of the semester, students have their weight, blood pressure, and cholesterol measured. What is the independent variable?

Nutrition Group

Compared to the population from which it comes, what is important to know about the standard deviation of the sample?

Unlike the population standard deviation, it requires you to consider the degrees of freedom in the denominator.

The distance from the mean, which is calculated as X-M for a sample, is called the

a deviation

Which of the following actions will NOT ALWAYS change the value of the mean?

adding/removing a new score to the distribution

The statistical measure that identifies a score that describes the center of a distribution or identifies the typical score is called

central tendency

Which of the following is NOT a way to describe the distribution of data?

class interval

Which of the following represents one of the two uses of a measure of central tendency?

compare two or more groups of data

Statistical methods that organize, summarize, or simplify data are called _______.

descriptive statistics

An organized tabulation of scores is called a:

frequency distribution

Which of the following type of graph would you use with an interval/ratio variable?

histogram

A researcher measures eye color for a sample of n = 50 people. Which measure of central tendency would be appropriate to summarize the measurements?

mode

In a positively skewed graph, most of the scores pile up ___________ of the graph.

on the left side

Using letter grades (A, B, C, D, and E) to classify student performance on an exam is an example of measurement on a(n) _______ scale of measurement.

ordinal

A researcher is curious about the average monthly cell phone bill for high school students in the state of Florida. If this average could be obtained for all of the high school students in Florida, it would be an example of a ______.

parameter

Which of the following indicates a sample standard deviation?

s

Although a research study is typically conducted with a relatively small group of participants known as a _________, most researchers hope to generalize their results to a much larger group that is inclusive of all of the participants known as a _________.

sample, population

The average verbal SAT score for the entire class of entering first-year college students in the US is 530. However, if you select a sample of 2000 first-year college students from colleges across the US and compute their average verbal SAT score you probably will not get exactly 530 (instead you get a mean of 550). What statistical concept is used to explain the natural difference that exists between the sample mean (M = 550) and the corresponding population mean (u = 530)?

sampling error

An experiment examines the effect of social skill training on the socialization behavior of autistic children; the independent variable is _______ and the dependent variable is _______.

social skill training; socialization behavior

The main goal of a z-score is to:

specify the exact location of a raw score in the distribution standardize the entire location

The standard deviation for a sample is an unbiased statistic because it

takes into account the degrees of freedom (N-1)

Which of the following is an example of a discrete variable?

the number of students in a psychology class

A researcher conducts an experiment to determine whether moderate doses of St. Johns Wort have any effect on memory for college students. One group receives the St. John's Wort while the second group receives a placebo (i.e., sugar pill). Group one is the ___________ and group two is the ____________

treatment condition; control condition