# Chapter 1: An Introduction To Statistics And Research Design

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The Two Branches of Statistics
How to Transform Observations into Variables
Three Types of Variables
Introduction to Hypothesis Testing

• 1.

### What “branch” of statistics uses numerical observations and incorporates them into an organized and informative summary of the data?

• A.

Sample

• B.

Population

• C.

Inferential

• D.

Descriptive

D. Descriptive
Explanation
Descriptive statistics is the branch of statistics that uses numerical observations and incorporates them into an organized and informative summary of the data. It focuses on summarizing and presenting data in a meaningful way, such as through measures of central tendency (mean, median, mode) and measures of dispersion (range, standard deviation). Descriptive statistics helps to describe and understand the characteristics of a dataset without making any inferences or generalizations about a larger population, making it the correct answer to this question.

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• 2.

### This "branch" of statistics uses sample data to make inferences about the broader population.

• A.

Descriptive

• B.

Inferential

• C.

Population

• D.

Sample

B. Inferential
Explanation
Inferential statistics is the branch of statistics that uses sample data to make inferences about the broader population. It involves analyzing and interpreting the data collected from a sample in order to draw conclusions or make predictions about the entire population. Unlike descriptive statistics, which simply summarizes and describes the sample data, inferential statistics allows us to generalize the findings to a larger population.

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• 3.

### Why are samples more commonly studied than populations?

• A.

Because most researchers are lazy

• B.

Because it is usually impossible to study an entire population

• C.

Because populations can only be studied if the data is continuous

• D.

Because samples are typically more accurate than populations

B. Because it is usually impossible to study an entire population
Explanation
The correct answer is because it is usually impossible to study an entire population. This is because populations can be very large and diverse, making it impractical and often impossible to collect data from every individual in the population. Instead, researchers often select a smaller subset of individuals, known as a sample, which is more manageable to study. By studying a sample, researchers can make inferences and draw conclusions about the larger population based on the information collected from the sample.

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• 4.

### Which type of variable could theoretically include an infinite number of possible values between any two consecutive numbers?

• A.

Ordinal

• B.

Continuous

• C.

Discrete

• D.

Nominal

B. Continuous
Explanation
Continuous variables are those that can take on any value within a certain range, including an infinite number of possible values between any two consecutive numbers. This means that there are no gaps or jumps in the possible values of a continuous variable. Examples of continuous variables include height, weight, and time. Unlike ordinal, discrete, and nominal variables, continuous variables have an unbroken range of values.

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• 5.

### Measuring a person's height in inches would involve using a(n) ______________ variable.

• A.

Ordinal

• B.

Interval

• C.

Nominal

• D.

Ratio

D. Ratio
Explanation
Measuring a person's height in inches would involve using a ratio variable. Ratio variables have a meaningful zero point and equal intervals between values. In this case, measuring height in inches allows for a meaningful zero point (no height) and equal intervals between each inch. This means that we can perform mathematical operations such as addition, subtraction, multiplication, and division on the measured values.

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• 6.

### Both ________ variables and __________ variables can be classified as scale observations.

• A.

Nominal; ordinal

• B.

Interval; ratio

• C.

Ordinal; interval

• D.

Discrete; continuous

B. Interval; ratio
Explanation
Interval and ratio variables can be classified as scale observations because they both have equal intervals between their values. Interval variables have no true zero point, while ratio variables have a true zero point. Both types of variables allow for mathematical operations such as addition and subtraction, making them suitable for quantitative analysis.

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• 7.

### Which of the following would make it difficult to determine if our independent variable truly had an effect on the dependent variable?

• A.

If our independent variable had too many levels

• B.

If our dependent variable was continuous

• C.

If we were using a between-groups research design

• D.

The presence of a confounding variable

D. The presence of a confounding variable
Explanation
The presence of a confounding variable would make it difficult to determine if our independent variable truly had an effect on the dependent variable because a confounding variable is an extraneous variable that is correlated with both the independent and dependent variables. This means that it could be influencing the dependent variable, making it unclear if the observed effect is due to the independent variable or the confounding variable. Therefore, the presence of a confounding variable can confound or distort the relationship between the independent and dependent variables, making it challenging to establish a causal relationship.

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• 8.

### A reliable measure:

• A.

Measures what it was intended to measure.

• B.

Predicts actual behavior.

• C.

Is consistent.

• D.

Co-varies with the independent variable.

C. Is consistent.
Explanation
A reliable measure is consistent, meaning it produces similar results when used repeatedly under the same conditions. This suggests that the measure is stable and dependable, as it consistently provides accurate and reliable data. Being consistent is an important characteristic of a reliable measure because it ensures that the results are not influenced by random factors and can be trusted for making accurate predictions or assessments.

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• 9.

### If the results from a personality test are different when given to the same person on two different occasions the the test is:

• A.

Not valid.

• B.

Not reliable but probably valid.

• C.

Not reliable.

• D.

Neither reliable nor valid.

C. Not reliable.
Explanation
If the results from a personality test are different when given to the same person on two different occasions, it indicates that the test is not reliable. Reliability refers to the consistency of the test results over time. In this case, since the results vary, it suggests that the test does not produce consistent results and therefore cannot be considered reliable. However, the validity of the test, which refers to whether it measures what it intends to measure, cannot be determined solely based on the given information.

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• 10.

### In a research study it is important to specify exactly how we will measure the variables that will be studied. In other words, it is important that we use:

• A.

Operational definitions.

• B.

Hypothesis testing.

• C.

Specificity of measurement.

• D.

Continuous observations.

A. Operational definitions.
Explanation
In a research study, it is crucial to clearly define and specify how the variables being studied will be measured. This ensures that the measurements are consistent and reliable, allowing for accurate analysis and interpretation of the data. Operational definitions provide a clear and specific description of how a variable will be measured or observed, ensuring that researchers are using the same criteria and procedures. This helps to eliminate ambiguity and allows for replication of the study by other researchers.

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• 11.

### If we made sure that each of our participants has an equal chance of being assigned to any condition in the experiment, we would be using:

• A.

Operational definitions.

• B.

A correlational study.

• C.

Random assignment.

• D.

Random selection.

C. Random assignment.
Explanation
Random assignment is the process of assigning participants to different conditions in an experiment, ensuring that each participant has an equal chance of being assigned to any condition. This helps eliminate bias and increase the internal validity of the study. Operational definitions refer to the specific procedures or measurements used to define and quantify variables. A correlational study examines the relationship between variables without manipulating them. Random selection is the process of selecting a representative sample from a larger population.

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• 12.

### Suppose we are interested in how people would rate three new flavors of ice cream. We decide to have participants try each of the three flavors and then rate each of them on a scale of 1 (hated it) to 10 (loved it). What type of research design is being used in this example?

• A.

Between-groups

• B.

Within-groups

• C.

Correlation

• D.

Independent groups

B. Within-groups
Explanation
The research design being used in this example is within-groups. This is because the participants are trying all three flavors of ice cream and rating each of them. This design allows for a comparison within the same group of participants, as they are experiencing all the conditions (flavors) being tested. It helps to eliminate individual differences and provides a more accurate assessment of how the participants rate each flavor.

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• 13.

### When your professor announces the average exam score for the class he is using:

• A.

Descriptive statistics.

• B.

Inferential statistics.

• C.

Nominal variables.

• D.

Ordinal variables.

A. Descriptive statistics.
Explanation
When the professor announces the average exam score for the class, he is using descriptive statistics. Descriptive statistics involves the collection, organization, and presentation of data in order to describe or summarize it. In this case, the professor is providing a summary measure (the average score) to describe the performance of the class as a whole. Inferential statistics, on the other hand, involves making inferences or predictions about a population based on a sample. Nominal and ordinal variables refer to different types of categorical data, which are not relevant to the scenario described.

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• 14.

### When researchers use descriptive statistics, they are:

• A.

Randomly assigning participants to conditions of an independent variable.

• B.

Drawing conclusions about the relationship between variables.

• C.

Using sample data to make general estimates about the larger population.

• D.

Organizing, summarizing, and communicating a group of numerical observations.

C. Using sample data to make general estimates about the larger population.
Explanation
When researchers use descriptive statistics, they are organizing, summarizing, and communicating a group of numerical observations. Descriptive statistics involve methods such as calculating measures of central tendency (mean, median, mode) and measures of variability (standard deviation, range) to summarize the data. These statistics are used to describe the characteristics of the sample data and make general estimates about the larger population from which the sample was drawn. However, descriptive statistics do not involve randomly assigning participants to conditions or drawing conclusions about the relationship between variables.

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• 15.

### A researcher is interested in the sleeping habits of first year college students. She selects 25 first year students from her college and asks them to complete a sleep survey. In this example the 25 students completing the survey would be the:

• A.

Independent variable.

• B.

Population.

• C.

Sample.

• D.

Dependent variable.

A. Independent variable.
Explanation
In this example, the researcher is interested in studying the sleeping habits of first-year college students. The researcher selects 25 first-year students from her college and asks them to complete a sleep survey. The number of students completing the survey is not being manipulated or changed by the researcher. It is a characteristic of the sample that the researcher has selected. Therefore, the 25 students completing the survey would be considered the independent variable, as they are not dependent on the researcher's manipulation or intervention.

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• 16.

### If your professor reports exam score averages to two decimal places - e.g., 77.65 - this would be considered a(n) _____________ observations.

• A.

Continuous

• B.

Ordinal

• C.

Discrete

• D.

Nominal

C. Discrete
Explanation
If the professor reports exam score averages to two decimal places, it means that the scores are measured with a level of precision that allows for differences of 0.01. This suggests that the scores can only take on specific, separate values and cannot be subdivided further. Therefore, the observations are considered discrete.

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• 17.

### There are three different types of Olympic medals: gold, silver, and bronze. What kind of variable describes the different types of Olympic medals?

• A.

Ratio

• B.

Interval

• C.

Ordinal

• D.

Nominal

A. Ratio
Explanation
The different types of Olympic medals (gold, silver, and bronze) can be categorized using an ordinal variable. An ordinal variable is a type of categorical variable where the categories have a natural order or ranking. In this case, the medals have a clear ranking with gold being the highest, silver being the second highest, and bronze being the third highest. A ratio variable, on the other hand, involves numerical values with a clear zero point, which is not applicable in this context. Interval and nominal variables do not have a natural order or ranking, making them unsuitable for describing the different types of Olympic medals.

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• 18.

### Using numbers to simply identify or label different objects or events involves:

• A.

Nominal variables.

• B.

Ordinal variables.

• C.

Interval variables.

• D.

Ratio variables.

D. Ratio variables.
Explanation
Using numbers to simply identify or label different objects or events involves ratio variables. Ratio variables have a meaningful zero point, and the intervals between values are equal. In this case, the numbers used to identify or label the objects or events have a clear zero point and the intervals between the numbers are equal. Therefore, it can be classified as a ratio variable.

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• 19.

### A popular sports drink company sampled 20 people who drink its product regularly and found that they performed better during a physical test than those who do not drink the product regularly. What might be a possible confound in the study?

• A.

The sample is small.

• B.

It rained the day of the physical test.

• C.

The company funding the test was biased.

• D.

People who are regular sports drinkers may be more athletic than those who are not.

C. The company funding the test was biased.
Explanation
The possible confound in the study could be that the company funding the test was biased. This means that the company may have a vested interest in promoting their product and could have influenced the test results in their favor. This bias could have led to a skewed perception of the performance of people who drink their product regularly, making the results unreliable.

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• 20.

### Suppose that, as part of a larger survey, we classify participants according to their classification in school. Our designations of freshman, sophomore, junior, or senior would be considered:

• A.

Variables.

• B.

Operational definitions.

• C.

Levels or conditions.

• D.

Confounds.

C. Levels or conditions.
Explanation
In this scenario, the designations of freshman, sophomore, junior, or senior represent different levels or conditions of classification in school. These levels or conditions are used to categorize the participants based on their classification in school.

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• 21.

### Psychologists studying infant memory want to determine at what age babies can remember specific events. An experimenter uses several puppets to demonstrate a series of actions while the infant watches. After a delay, the experimenter records how many of the actions the child imitates when playing with the puppets. The dependent variable is the:

• A.

Activity level of the child.

• B.

Type of puppet used by the experimenter.

• C.

Number of imitated actions.

• D.

Length of the experiment.

C. Number of imitated actions.
Explanation
The dependent variable in this study is the number of imitated actions. This is because the researchers are interested in determining at what age babies can remember specific events, and they are measuring this by observing how many of the actions the child imitates after a delay. The other options, such as the activity level of the child, type of puppet used, and length of the experiment, are not being directly measured or manipulated in this study.

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• 22.

### A between-groups design:

• A.

Involves each participant participating in all levels of the experiment.

• B.

Includes only one condition.

• C.

Is sometimes referred to as a longitudinal design.

• D.

Involves each participant experiencing only one level of the experiment.

D. Involves each participant experiencing only one level of the experiment.
Explanation
A between-groups design involves each participant experiencing only one level of the experiment. This means that different groups of participants are assigned to different conditions or levels of the independent variable. Each participant is exposed to only one level of the experiment, allowing for a comparison between the groups. This design is commonly used to examine the effects of different conditions or treatments on participants' responses or behaviors.

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• 23.

### Suppose a researcher randomly assigns participants to three groups and examines their ability to solve complex mathematical problems under conditions of no noise, continuous noise, or random noise. What type of research design is the researcher using?

• A.

Correlational

• B.

Repeated measures

• C.

Within-groups

• D.

Between-groups

D. Between-groups
Explanation
The researcher is using a between-groups research design because participants are randomly assigned to three different groups. Each group is exposed to a different condition (no noise, continuous noise, or random noise) and their ability to solve complex mathematical problems is measured. This design allows the researcher to compare the performance of participants in different groups and determine the effect of the different noise conditions on their ability to solve the problems.

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• 24.

### If we were interested in studying the effect of child abuse on academic achievement we would probably use a ___________ study because of ethical issues involved in employing random assignment.

• A.

Within-groups

• B.

Between-groups

• C.

Experimental

• D.

Correlational

D. Correlational
Explanation
In this scenario, a correlational study would be the most appropriate method to study the effect of child abuse on academic achievement due to ethical issues involved in employing random assignment. This is because it would be unethical to randomly assign children to groups where they may potentially be exposed to child abuse. Instead, a correlational study would allow researchers to examine the relationship between child abuse and academic achievement without manipulating or assigning participants to different conditions. This type of study would provide valuable insights into the association between these variables while maintaining ethical considerations.

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• 25.

### If a market research company studies the television viewing habits of 1,000 randomly selected families and uses the information to make inferences about the viewing habits of all families in the United States, they are utilizing:

• A.

Descriptive statistics.

• B.

A correlational research design.

• C.

A within-groups research design.

• D.

Inferential statistics.

D. Inferential statistics.
Explanation
When a market research company studies the television viewing habits of 1,000 randomly selected families and uses this information to make inferences about the viewing habits of all families in the United States, they are utilizing inferential statistics. Inferential statistics involves making predictions or generalizations about a population based on a sample. In this case, the sample of 1,000 families is used to make inferences about the television viewing habits of all families in the United States. This allows the company to draw conclusions and make decisions based on the data collected from the sample.

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• 26.

### The main difference between an interval variable and a ratio variable is that an interval variable:

• A.

Does not have a true zero point.

• B.

Has equal intervals between numbers.

• C.

Does not preserve a rank order in the assignment of numbers.

• D.

Is used only for placing participants into categories.

A. Does not have a true zero point.
Explanation
An interval variable does not have a true zero point, meaning that the value of zero does not represent the absence of the attribute being measured. For example, in temperature measurement, a value of zero does not mean there is no temperature; it simply represents a point on the scale. In contrast, a ratio variable does have a true zero point, where zero indicates the complete absence of the attribute.

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• 27.

### A _________ variable meets the criteria for either an interval variable or a ratio variable.

• A.

Independent

• B.

Scale

• C.

Dependent

• D.

Discrete

B. Scale
Explanation
A scale variable meets the criteria for either an interval variable or a ratio variable. This is because a scale variable represents a measurement that has a meaningful order and equal intervals between values. Interval variables have equal intervals between values but do not have a true zero point, while ratio variables have equal intervals and a true zero point. Therefore, a scale variable can be classified as either an interval variable or a ratio variable depending on the presence or absence of a true zero point.

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• 28.

### If we rated friendliness of store clerks on a scale from 1-5, the ratings would represent a(n) ___________ variable.

• A.

Ratio

• B.

Nominal

• C.

Interval

• D.

Ordinal

C. Interval
Explanation
The ratings of friendliness of store clerks on a scale from 1-5 can be considered as an interval variable. This is because the ratings have a meaningful numerical value and the intervals between the ratings are equal. However, it is important to note that the zero point on this scale does not represent the absence of friendliness, but rather the lowest level of friendliness.

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• 29.

### A variable shows reliability when:

• A.

It is accepted in the Encyclopedia of Psychology.

• B.

Enough experimenters decide to use it in their research.

• C.

The same results are obtained each time it is measured.

• D.

Other researchers demonstrate that it does measure what it is supposed to measure.

C. The same results are obtained each time it is measured.
Explanation
When a variable shows reliability, it means that consistent and similar results are obtained each time it is measured. This indicates that the variable is stable and dependable, allowing researchers to have confidence in its accuracy and consistency. Reliability is an important aspect of scientific research as it ensures that the measurements or observations of the variable are not affected by random or extraneous factors, leading to more valid and trustworthy results.

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• 30.

### One reason for doing correlational research is to evaluate the relationship between two variables that are related to each other, either positively or negatively. However, a correlation is vulnerable to what variable, which systematically co-varies with the variable of interest?

• A.

Noise

• B.

Extraneous

• C.

Confounding

• D.

Dependent

C. Confounding
Explanation
Correlational research is conducted to assess the relationship between two variables. However, this type of research is susceptible to the influence of confounding variables. Confounding variables are those that are not the primary focus of the study but still affect the relationship between the variables of interest. They can introduce bias and lead to incorrect conclusions about the relationship being studied. Thus, it is important to account for and control for confounding variables to ensure accurate results in correlational research.

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• 31.

### The numbers on athletes' uniforms are an example of a(n) _________ variable.

• A.

Ordinal

• B.

Nominal

• C.

Interval

• D.

Ratio

B. Nominal
Explanation
The numbers on athletes' uniforms are an example of a nominal variable because they represent categories or labels rather than a quantitative value. The numbers serve as identifiers for the athletes and do not have any inherent order or numerical meaning. Each number is simply assigned to a specific athlete without any numerical relationship between them.

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• 32.

### In the famous Zimbardo prison study, Stanford students were assigned to be either a prisoner or a guard so that the experimenters could examine prison life behaviors and interactions. The experiment was intended to run for two weeks but was stopped after only six days because of the brutal behavior of the guards and the depression of the prisoners. What was the independent variable in this study?

• A.

The length of the study

• B.

The participants' behavior

• C.

The Stanford campus

• D.

The role of prisoner or guard

D. The role of prisoner or guard
Explanation
The independent variable in the Zimbardo prison study was the role of prisoner or guard. This means that the researchers manipulated and controlled whether participants were assigned to be prisoners or guards. The purpose of this manipulation was to examine how the assigned role affected the behaviors and interactions of the participants. The study aimed to investigate the impact of the role on individuals' behavior and the dynamics of prison life.

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• 33.

### Suppose that a student taking a psychology course proposes to test the hypothesis that “playing violent video games leads men to have negative attitudes toward women.” After being asked to operationally define her variables the student proposes the following four hypotheses. Which of the following hypotheses include the best operational definitions for this study?

• A.

Playing video games for more than 3 hours a day causes college-aged men to have negative feelings toward women.

• B.

Playing the video game Destroyer causes men to have worse attitudes toward women than if they play a less violent video game.

• C.

• D.

Playing the video game Destroyer for 2 hours a day for one week will cause men to have negative attitudes toward women as measured by the Hostility Toward Women scale.

D. Playing the video game Destroyer for 2 hours a day for one week will cause men to have negative attitudes toward women as measured by the Hostility Toward Women scale.
Explanation
The answer includes the best operational definitions for the study because it specifies the duration of playing the video game (2 hours a day for one week) and the measure of negative attitudes toward women (Hostility Toward Women scale). This provides clear and measurable variables for the study, allowing for accurate data collection and analysis.

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• 34.

### Lawrence is testing a series of new commercials on a sample audience for an advertising company. He wants to see which of 10 commercials receives the highest rating from audiences but he wants to use a different audience for each commercial. What design should Lawrence use?

• A.

Quasi-experiment

• B.

Between-groups design

• C.

Correlation

• D.

Within-groups design

B. Between-groups design
Explanation
Lawrence should use a between-groups design for his study. This design involves assigning different audiences to each commercial, allowing for a comparison between the commercials. By using different audiences for each commercial, Lawrence can ensure that the ratings are not influenced by individual differences within the audience. This design will provide a clear understanding of which commercial receives the highest rating from the sample audience.

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• 35.

### Statistical methods that use sample data to draw inferences about larger populations are called:

• A.

Population statistics.

• B.

Sample statistics.

• C.

Descriptive statistics.

• D.

Inferential statistics.

D. Inferential statistics.
Explanation
Inferential statistics is the correct answer because it refers to the statistical methods that use sample data to make inferences or draw conclusions about larger populations. This involves analyzing the sample data and using it to make predictions or generalizations about the population as a whole. Descriptive statistics, on the other hand, simply summarize and describe the characteristics of the sample data. Population statistics and sample statistics are not accurate terms to describe this concept.

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• 36.

### A subset of data drawn from the larger population of interest is a:

• A.

Variable.

• B.

Population.

• C.

Continuous observation.

• D.

Sample.

D. Sample.
Explanation
A subset of data drawn from the larger population of interest is referred to as a sample. This sample is selected to represent the characteristics of the population and is used to make inferences or draw conclusions about the entire population. By studying the sample, researchers can gather insights and make predictions about the larger group from which it was drawn.

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• 37.

### A measure is said to be valid if:

• A.

If the specific procedures used in the measure are identified.

• B.

Is low in measurement error.

• C.

Its results are consistent.

• D.

Measures what it is supposed to measure.

D. Measures what it is supposed to measure.
Explanation
The given answer is "measures what it is supposed to measure." This is because a measure is considered valid if it accurately assesses the construct or concept it is intended to measure. In other words, the measure should capture the intended information or attribute without any bias or distortion. The other options mentioned in the question, such as identifying specific procedures, low measurement error, and consistent results, are important aspects of measurement but do not directly address the concept of validity.

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• 38.

### In a within-groups design:

• A.

Random assignment is always used.

• B.

Each condition contains different people.

• C.

Participants are randomly assigned to conditions.

• D.

Participants experience all conditions of the study.

D. Participants experience all conditions of the study.
Explanation
In a within-groups design, participants experience all conditions of the study. This means that each participant is exposed to all levels of the independent variable. This design allows for comparisons to be made within the same group of participants, increasing statistical power and reducing the influence of individual differences. It also helps control for extraneous variables, as each participant serves as their own control. This design is particularly useful when it is not feasible or ethical to recruit different groups of participants for each condition.

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• 39.

### What is the primary difference between descriptive and inferential statistics?

• A.

Inferential statistics typically have greater reliability than descriptive statistics.

• B.

Descriptive statistics are better able to control confounding variables than inferential statistics

• C.

Inferential statistics typically involve larger amounts of data than descriptive statistics.

• D.

Inferential statistics allow researchers to draw conclusions about populations while descriptive statistics simply organize and summarize data.

D. Inferential statistics allow researchers to draw conclusions about populations while descriptive statistics simply organize and summarize data.
Explanation
Inferential statistics involve making inferences and drawing conclusions about populations based on sample data, while descriptive statistics focus on organizing and summarizing data without making any generalizations. This means that inferential statistics allow researchers to make broader claims and predictions about the entire population, whereas descriptive statistics only provide a summary of the data at hand.

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• 40.

### Random assignment in experiments is important because:

• A.

It helps to control confounding variables.

• B.

It ensures that the measures used are valid.

• C.

It eliminates the problem of dependent variables.

• D.

It ensures that the measures used are reliable.

A. It helps to control confounding variables.
Explanation
Random assignment in experiments is important because it helps to control confounding variables. Confounding variables are factors that may influence the outcome of an experiment but are not the variables of interest. Random assignment ensures that participants are assigned to different groups or conditions randomly, minimizing the potential for systematic differences between groups. By doing so, researchers can be more confident that any differences observed between groups are due to the manipulation of the independent variable and not to other factors. This increases the internal validity of the study and allows for more accurate conclusions to be drawn.

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• 41.

### If a psychologist ranks the patients on a hospital ward in terms of the severity of their illness - that is, the patient with the worst prognosis is given a rank of 1, the patient with the second worst prognosis is given a rank of 2, and so on - she is using a(n) ________ variable.

• A.

Ratio

• B.

Ordinal

• C.

Interval

• D.

Nominal

B. Ordinal
Explanation
In this scenario, the psychologist is ranking the patients based on the severity of their illness. This ranking system implies that there is a specific order or hierarchy among the patients, where the patient with the worst prognosis is given the highest rank and the patient with the second worst prognosis is given the second-highest rank, and so on. Therefore, the psychologist is using an ordinal variable, as it involves assigning a rank or order to the patients based on a specific criterion.

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• 42.

### The total number of Olympic medals won by a country is an example of which kind of variable?

• A.

Ratio

• B.

Ordinal

• C.

Interval

• D.

Nominal

A. Ratio
Explanation
The total number of Olympic medals won by a country is an example of a ratio variable because it represents a quantitative measurement with a meaningful zero point. The zero in this case indicates that a country has not won any medals, and the numbers can be compared and analyzed using mathematical operations such as addition, subtraction, multiplication, and division.

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• 43.

### The variable that is measured to determine if the independent variable had an effect is referred as the _________ variable.

• A.

Change

• B.

Operational

• C.

Dependent

• D.

Confounding

C. Dependent
Explanation
The variable that is measured to determine if the independent variable had an effect is referred to as the dependent variable. This variable is dependent on the independent variable and its value changes based on the manipulation of the independent variable. By measuring the dependent variable, researchers can assess the impact or influence of the independent variable on the outcome of the study.

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• 44.

### If we believe we are creating a measure of intelligence but in fact it measures creativity, we would say that our measure lacks:

• A.

Consistency.

• B.

Levels.

• C.

Reliability.

• D.

Validity.

D. Validity.
Explanation
If we mistakenly believe that we are measuring intelligence but are actually measuring creativity, it means that our measure does not accurately assess what it claims to measure. This lack of alignment between the intended construct (intelligence) and the actual construct being measured (creativity) indicates a lack of validity. Validity refers to the extent to which a measure accurately captures the construct it is intended to measure. In this case, the measure lacks validity because it does not measure intelligence as intended.

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• 45.

### Suppose students are randomly assigned to either get positive feedback or not get positive feedback for their performance on daily quizzes and we measured their attitudes toward the class at the end of the semester. What is the independent variable in this study?

• A.

The students

• B.

Performance on the quizzes

• C.

Their attitude toward the class

• D.

Getting positive feedback or not getting positive feedback

D. Getting positive feedback or not getting positive feedback
Explanation
The independent variable in this study is "getting positive feedback or not getting positive feedback". This is because it is the variable that is being manipulated by the researchers. They are randomly assigning students to either receive positive feedback or not receive positive feedback for their performance on daily quizzes. The researchers are interested in how this manipulation affects the students' attitudes toward the class at the end of the semester.

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• 46.

### _________ studies are useful for simply establishing an association between variables but do not provide information regarding cause and effect.

• A.

Between-groups

• B.

Within-groups

• C.

Experimental

• D.

Correlational

D. Correlational
Explanation
Correlational studies are useful for simply establishing an association between variables but do not provide information regarding cause and effect. In a correlational study, researchers measure and analyze the relationship between two or more variables to determine if they are related or associated with each other. However, correlational studies cannot determine the cause and effect relationship between variables because they do not involve manipulation of variables or control over extraneous factors. Therefore, while correlational studies are valuable in identifying relationships, they cannot establish causation.

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• 47.

### 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:

• A.

Mode.

• B.

Population.

• C.

Median.

• D.

Sample.

D. Sample.
Explanation
In this question, the college students at 20 campuses around the country who were polled represent a smaller group within the larger population of college students. This smaller group is called a sample. The sample is used to gather information and make inferences about the larger population. The other options, mode, median, and population, do not accurately describe this specific group of college students that were polled.

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• Mar 20, 2023
Quiz Edited by
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• Jun 07, 2011
Quiz Created by
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