PSY 216

Of the values listed, which is the highest value in the interval that ranges from 3 to 7?

7.8

Suppose random selection is used to recruit 15 classmates to participate in a research study that has three levels of the independent variable (IV). During the random selection process, an online random number generator generates this string of digits: 2 2 0 2 1 2 2 0 2 2 2 1 0 1 0 Based on this output, how many participants would be assigned to the third level of the IV?

8

Larry is creating a grouped frequency table and wants to determine the appropriate size for his intervals. His data set has a range of 60, and he would like to have 5 different intervals. What is the appropriate interval size for Larry's table?

12

Several times, Martha has seen her dog act strangely while a school bus was driving past her home, even though the dog was not near a window or otherwise able to see the bus. Martha suspects that the bus makes a sound the dog can hear even if Martha cannot. Martha's explanation is reasonable. On the other hand, it may be that Martha has fallen prey to a(n):

Illusory correlation -the phenomenon of believing one sees an association between variables when no such association exists

Symbol for sample size

N

A professor wants to determine the average age of all students enrolled in statistics courses at Whatsamatta U. The professor obtains data from 167 currently enrolled students. In this context, the variable of interest would be:

age

Another term for a research hypothesis is:

alternative hypothesis

Information on baseball players in Major League Baseball—including position played, salary, and batting average—is collected for a study. To look at the distribution of the variable "position," it would be best to make a:

bar graph

Type I errors are the result of chance, so it is not possible to know if one has occurred in a particular study. In order to avoid basing decisions on faulty claims, one should:

believe the claim if it is supported by many studies

Megan is a researcher studying memory in older adults. For one variable, memory, she has organized her participants' scores into a frequency distribution and wants to graph the results. Which of these could Megan use?

a histogram

Dr. Boaz wants to publish the results of his study. Which study would MOST likely be published?

a study in which he rejected the null hypothesis

If the mean is greater than the median, then the distribution has:

a tail on the right (skewed right)

Scale Variable

a variable that meets the criteria for an interval variable or a ratio variable

Interval Variable

a variable used for observations that have numbers as their values; the distance (or interval) between pairs of consecutive numbers is assumed to be equal

Individuals who believe in psychic abilities are more likely to remember the one event that a famous psychic correctly predicted and forget the 25 incorrect predictions due to _____ bias

confirmation

Crowdsourcing is a form of:

convenience sampling

A study comparing amount of time spent watching television each week and annual income is considered ________ research

correlational

A study comparing working adults' increases in salary and their increases in spending would MOST likely be conducted as:

correlational research

A histogram is a(n) _____ that can be viewed in graph form

frequency distribution

A ______ ______ ______ is a visual depiction of data that reports frequencies within a given interval rather than the frequencies for a specific value.

grouped frequency table

Students collected 600 dimes and recorded the mint year for each one. To look at the distribution of the variable "year minted," it would be BEST to make a:

histogram

One thing that makes dot plots especially easy to read is the:

human brain's ability to quickly apprehend small quantities

What is true about a distribution that has both a ceiling effect and a floor effect?

it could be negatively or positively skewed, or neither

In examining whether gender predicts political party affiliation, Republican, Democrat, and Independent would be ________ variable

levels of independent

Marla wants to predict salary from intelligence quotient; she should use a _____ to plot the data

line graph

In a histogram, the bars are stacked one against the next, with the intervals arranged from _____ numbers on the left to _____ numbers on the right

lower; higher

Acme Ice Cream Company conducts a survey. The survey asks about their customers' emotional state when eating ice cream. The most common response to the survey is "very happy." In other words, "very happy" was the _____ answer given

modal

A group of biology students takes a test. Their teacher, Mrs. Joshua, graphs their scores using a histogram. She notices that very few students score poorly on the test. Rather, a majority of students achieve a score of 80% or higher. This trend could be described as a _____ distribution

negatively skewed

If a majority of scores in a distribution are clustered on the positive end, it is defined as a _____ distribution Data has a distribution with a tail that extends to the left, in a negative direction

negatively skewed

A local television station invited viewers to call the station to respond to a poll on the local election. They later stated, "Over 2500 viewers responded to our poll about the sales tax question on the election ballot. Of our viewers, 75% are opposed to the proposal for an additional 0.5% sales tax. The poll has a margin of error of plus or minus 3%." Their results as reported are _____ because _____.

not reliable; this is a volunteer sample

In order to make the pictures proportional in pictorial graphs, the size of group differences suggested by the pictures is:

often exaggerated

Dr. Aishabi wants to examine whether the average final score in his introductory psychology class, recorded as a percentage, differs depending on students' majors. To graph these data he should use a(n) _____ chart

pareto

Subjective probability is another term for:

personal probability

A _____ uses pictures to represent data with few independent variable levels and a scale dependent variable

pictorial graph

Pictorial graphs are common in _____ but not in _____

popular media; research journals

With ________ skewed data, the distribution's tail extends to the right, in a positive direction

positively

When a set of scores is displayed in histogram form, one tail extends to the right of the distribution. This is a _____distribution

positively skewed

Mathematically, _____ can be defined as the number of successful outcomes divided by the total number of trials

probability

The _____ is the easiest measure of variability to calculate

range

Dr. Fairweather is interested in studying the relationship b/t test scores, coded from zero to 100%, and number of hours spent studying for the test by college students. In this example, number of hours spent studying for the test is a _______ variable

ratio

Reproducibility is an alternate term for _____ of scientific results

replication; the duplication of scientific results, ideally in a different context or with a sample that has different characteristics

A hypothesis that proposes a difference worthy of being studied is called the _____ hypothesis

research

In the formula for the standard deviation of a sample, what does M represent?

sample mean

Bonnie is interested in studying the relationship between a college student's test scores and the number of hours the student spends watching TV. In this case, she should use a:

scatterplot

Professor Karabo wants to examine whether students' scores on the first quiz in her class, recorded as percentages, predict overall final grades, also recorded as percentages. To graph the data she should use a:

scatterplot

If the mean is less than the median, then the distribution has:

skewed left (tail to the left)

Xavier wants to show his office how much of the budget is spent on advertising, health care, office supplies, and so on. He is thinking of using a pie chart, but a better approach would be to use a:

table

Validity

the extent to which the test actually measures or predicts what it promises

We say that a distribution is negatively skewed if:

the left side of the histogram extends farther out than the right side

Researchers are less likely to publish the results in which: -there is a Type II error -the null hypothesis is rejected -the null hypothesis is not rejected -there is a Type I error

the null hypothesis is not rejected

Journals typically publish articles in which:

the null hypothesis is rejected

How to label axes on a histogram

the values of the variable on the x-axis and the frequencies on the y-axis

A professor who teaches a large lecture course would like to know if his students are enjoying the class. To find out, he invites them to go online and fill out a quick survey. A week later, he compiles the results from about three dozen responses and is discouraged to find that many of the students find the lectures confusing or otherwise unhelpful. What is the biggest problem with the survey data?

this was a volunteer survey, so results are likely to be skewed

Audrey wants to examine the average salary of cricket players from 1995 to 2015. To graph the data she should use a:

time plot

Jayden wants to examine the percentage of British males who smoked for each of the years 2000-2014. To graph the data he should use a:

time plot

Anna's friend asks whether or not a particular professor Anna took a class from last semester is strict. Before Anna answers, she begins to think back over her interactions with the professor. Which behavior BEST illustrates the confirmation bias?

trying to recall specific instances when the professor was very strict confirmation bias: our usually unintentional tendency to pay attention to evidence that confirms what we already believe and to ignore evidence that would disconfirm our beliefs

For the study she is conducting, Dr. Fey decides to use the Beck Depression Inventory as her measure b/c it has been shown to produce similar scores over time. Depending on the purpose of Dr. Fey's study, however, this may not be a _________ measure

valid

When deciding what type of graph to use, first examine the:

variables

A Type II error occurs when researchers:

when we do not reject the null hypothesis but the null hypothesis is false

A Type I error occurs when researchers:

when we reject the null hypothesis but the null hypothesis is correct

Types of cars driven is an example of something that would be plotted on the _____ of a bar graph

x-axis

A floor effect is a situation where:

a constraint keeps scores from going below a given number

The value of an observation is 216; the value of the mean is 221.3. The value of the deviation is:

216 - 221.3 = -5.3

Which statement about the line of best fit in a line graph is false? -It proves that the x-axis variable causes the change in the y-axis variable -It allows for the prediction of y scores based on x values -It minimizes the distances of the dots to the line -It clearly shows the relationship between the variables

It proves that the x-axis variable causes the change in the y-axis variable

Which statement describing the mean is true? -The mean cannot be a whole number -The mean cannot be positive -The mean can be negative -The mean cannot be negative

The mean can be negative

What could be the outcome of an experiment-based study?

The null hypothesis is not rejected

Many manufacturers conduct focus groups and do surveys to find out what consumers want in a product. They are also interested in what type of packaging will entice shoppers to buy their products. Brand Z cereal is considering changing their package design to make it more attractive, so that shoppers might buy it on impulse. Changing packaging is expensive, however, so they want to be certain that the new package is attractive. In this scenario, a Type I & II error is _____ the package design when it will _____

Type I: deciding to change; not entice more shoppers to buy their cereal Type II: not changing; help sell their cereal

A ceiling effect is a situation where:

a constraint keeps scores from going above a given number

Organizing one's raw scores into a(n) _____ distribution allows one to see the pattern of responses for a variable

frequency

Muhammad wants to use intelligence quotient (IQ) to predict salary. Salary is the _____ variable

dependent

When assessing a graph, students should try to identify the _____ variable, or the variable that the researchers are trying to predict

dependent

When a frequency table reports frequencies as percentages, what do the percentages represent?

each score's frequency, divided by the total number of observations

A study comparing one group of participants randomly assigned to receive a drug with another group of participants randomly assigned to receive a placebo is an example of an _________ that has a ________-_______ research design

experiment; between-groups

A study comparing one group of participants after they receive a drug with the same group of participants after they receive a placebo is an example of an __________ that has a _______-_________ research design

experiment; repeated-measures

A study comparing one group of participants after they receive a drug with the same group of participants after they receive a placebo is an example of an _________ that has a ______-_______ research design

experiment; within-groups

Aisha collects body mass index scores for a classroom of third graders. She graphs the scores' distribution using a histogram. She notices that the distribution is exhibiting a positive skew. This variable might be subject to a(n) _____ effect

floor