Question 1

When researchers study multiple groups and report the means for each group,they are reporting:

Accepted Answer

The means of each group are a form of descriptive statistics, which summarize the data and provide information about the central tendency of each group. The other options (B, C, and D) are also types of descriptive statistics, but they do not specifically address the act of reporting means for multiple groups.

Question 2

Carlos reads an article looking for a measure of central tendency.Which of the following might he find?

Accepted Answer

The measure of central tendency refers to the value that represents the center of a set of data. The median is a measure of central tendency that represents the middle value in a dataset after the data has been put in order. The other answer choices are not measures of central tendency.

Question 3

Suppose a researcher studying the effect of having a pet on elderly people's subjective well-being does NOT use a control group in his study.What type of validity is this measure lacking?

Accepted Answer

The measure is lacking internal validity because without a control group, the researcher cannot confidently conclude that any changes in subjective well-being are solely due to having a pet and not other extraneous variables.

Question 4

If you want to know how far apart scores in a data set tend to be,you could use the:

Accepted Answer

The best choice to understand how far apart scores in a dataset tend to be is the standard deviation. The standard deviation measures the amount of variation or dispersion of a set of values from its mean. It provides a more accurate and precise measure of the spread of the data than the mean, median, or mode.

Question 5

The mean,median,and mode are all examples of:

Accepted Answer

The mean, median, and mode are all measures of central tendency, which means they are used to determine the typical or average value in a set of data. Inferential statistics refer to using data from a sample to make inferences about a larger population, types of variability refers to the spread or dispersion of data, and correlational measures are used to determine the relationship between two variables.

Question 6

The statistic that involves the basic arithmetic average of a set of scores is known as the:

Accepted Answer

The basic arithmetic average of a set of scores is known as the mean. The mode refers to the most frequently occurring value, the range refers to the difference between the highest and lowest values, and the median refers to the middle value in a data set.

Question 7

If a researcher's data are reliable:

Accepted Answer

Reliability refers to the consistency and precision of data collection methods. While reliable data is important, it is not enough to ensure validity, which refers to whether the research actually measures what it intends to measure. Therefore, reliable data may still involve a high level of systematic error (such as measurement bias) that affects the validity of the research findings. Participant reactivity (the effect of participants altering their behavior due to being observed) and cultural sensitivity are separate issues that may or may not be related to the reliability of data collection.

Question 8

Suppose a research study does a good job at making sure the results generalize to the real world,but does not do a good job preventing confounds.This research study:

Accepted Answer

External validity refers to the extent to which the results of a study can generalize to real-world situations. This study does a good job at achieving external validity, meaning the results can be applied to real life. However, it does not do a good job preventing confounds, which means it lacks internal validity. Internal validity refers to the extent to which we can be confident in stating that the independent variable causes the dependent variable. Therefore, although the results may be applicable to real-world scenarios, we cannot be sure that the independent variable caused any observed effects.

Question 9

The most frequently occurring score in a data set is known as the:

Accepted Answer

The most frequently occurring score is known as the mode. The mean is the average of all scores, the range is the difference between the highest and lowest scores, and the standard deviation is a measure of the dispersion of scores from the mean.

Question 10

The range and standard deviation are examples of:

Accepted Answer

The range and standard deviation are both measures of variability, specifically how spread out a set of data is.

Question 11

Suppose a researcher studying social anxiety in children uses a measure of "fidgeting" that indexes hyperactivity instead of social anxiety.What type of validity is this measure lacking?

Accepted Answer

The measure is lacking construct validity, as it is not measuring the construct of social anxiety as intended, but instead is measuring hyperactivity.

Question 12

If a participant always shows fast reaction times on a visual task not because she is good at the task but because she can hear the experimenter start the presentation and can get ready for the stimulus,her data will show a high level of:

Accepted Answer

The answer of If a participant always shows fast reaction...

Question 13

If you list a set of scores from the lowest value to the highest,then take the middle value to indicate what a typical score is,you are using the:

Accepted Answer

The question is asking for the measure of central tendency that represents a typical score when the set of scores is listed in order. This is exactly the definition of the median, which is the middle value when the set of scores is listed in order. The mean is calculated by adding up all the scores and dividing by the number of scores, and is not necessarily the middle value. The mode is the most frequent value and may not represent what a typical score is. The range is the difference between the highest and lowest values and does not indicate what a typical score is.

Question 14

Ashley is an undergraduate research assistant in a lab investigating preschool children's science knowledge.She is examining the items on the science knowledge assessments to ensure that they actually measure science,and not some other concept.What type of validity is she addressing?

Accepted Answer

Construct validity refers to the extent to which a test measures the intended construct or concept. In this case, Ashley is checking to see if the science knowledge assessments are actually measuring science knowledge, which would fall under construct validity. External validity refers to the generalizability of findings to other populations or situations, internal validity refers to the extent to which a study or experiment measures what it claims to measure, and reliability refers to the consistency and stability of results over time or across raters. While all of these types of validity are important in research, they are not the focus of Ashley's specific task in this scenario.

Question 15

A store owner wants to make sure she has enough shirts in the right sizes in her inventory,so she buys a lot of shirts in the most popular size.In order to make this purchase,what type of statistic would she want to know?

Accepted Answer

The mode would tell the store owner which size is the most popular among customers, which would help her make an informed decision about which size to buy in bulk. The other statistics (mean, standard deviation, range) wouldn't necessarily provide her with this specific information.

Question 16

Suppose a researcher intended to study people's levels of happiness by monitoring how often they smile or laugh when watching a movie.If this measurement does not really indicate level of happiness,psychologists would say that the data are NOT:

Accepted Answer

Validity refers to whether a measure actually measures what it is intended to measure. If the measurement of smiling or laughing during a movie does not actually indicate level of happiness, then the data gathered from it would not be considered valid. Reliability refers to the consistency of a measure, systematic refers to the organization of data, and event related refers to data collected from a specific event or time frame. While these are important concepts in research, they do not directly relate to the issue of validity in this scenario.

Question 17

If a researcher finds that a participant produces different scores on a task each time the participant engages in that task,a researcher can conclude that:

Accepted Answer

If a participant produces different scores on a task each time they engage in that task, it suggests that the measurements are not reliable. Reliability refers to the consistency or stability of measurements, and if scores vary widely across repeated administrations of the same task, it indicates a lack of reliability.

Question 18

Why is the range often the LEAST useful measure of central tendency?

Accepted Answer

The range only considers the two extreme scores and doesn't take into account the other data points. It doesn't provide information about the variability within the dataset, which can be important in understanding the spread of data.

Question 19

The values in a data set span from 60 to 90.If a researcher knows this,then the researcher is aware of the:

Accepted Answer

The range is the difference between the largest and smallest values in a data set. In this case, the range would be 90 - 60 = 30. Therefore, the researcher would be aware of the range.

Question 20

In what way are internal validity and external validity different?

Accepted Answer

External validity refers to the extent to which findings can be generalized to other populations, settings, and situations. Internal validity, on the other hand, refers to the degree to which a study provides evidence for a cause-effect relationship between the independent and dependent variables, without the influence of confounding variables. Therefore, external validity is concerned with generalization while internal validity is concerned with experimental control.

Quiz 2: Research Methodology