Learn Before
Based on the case context, decide how the researcher should apply descriptive statistics to describe their data. Explain the two different types of measures the researcher needs to calculate and specify what each type of measure will communicate about the sample's performance.
Case context: A student researcher is examining cognitive performance in a sample of participants. After administering a test, the researcher receives a list of scores but is unsure how to present these findings. The researcher wants to summarize the typical performance of the group as well as how much the scores vary across the sample.
Question: Based on the case context, decide how the researcher should apply descriptive statistics to describe their data. Explain the two different types of measures the researcher needs to calculate and specify what each type of measure will communicate about the sample's performance.
Sample answer: To summarize the findings, the researcher needs to use descriptive statistics. First, they should calculate a measure of central tendency (such as the mean, median, or mode) to describe the typical or average test score of the sample. Second, they should calculate a measure of dispersion (such as the range, standard deviation, or variance) to determine how spread apart or variable the test scores are. Together, these measures summarize the overall distribution of the collected data.
Key points:
- Descriptive statistics are needed to summarize and organize the test score data from the sample.
- The researcher must calculate a measure of central tendency (mean, median, or mode) to describe average scores.
- The researcher must calculate a measure of dispersion (range, standard deviation, or variance) to describe the spread of scores.
- These calculations describe the sample data rather than generalizing to a population.
Rubric: The response should be graded on whether it correctly explains that: (1) descriptive statistics must be used to summarize and organize the test data; (2) a measure of central tendency is required to describe the average or center score; and (3) a measure of dispersion is required to show the spread or variation of the scores.
0
1
Tags
KPU
Research Methods in Psychology - 4th American Edition @ KPU
Related
Correlation Coefficient
Sample Statistic
Descriptive Statistics in Experimental Research
Descriptive Statistics in Non-Experimental Research
Inferential Statistics
Understanding Descriptive Statistics
Scatterplot
Measures of Central Tendency
Measures of Dispersion
Forms of Statistical Relationship
Mean
Standard Deviation
Bar Graph
Line Graph
What is the primary purpose of using descriptive statistics in psychological research?
Match each category of descriptive statistics with the specific goal it accomplishes when a researcher is summarizing their data.
A researcher finds that a distribution of scores on a memory task is negatively skewed, meaning there are a few extremely low scores that pull the tail of the distribution to the left. Arrange the following measures of central tendency in order from the lowest numerical value to the highest numerical value based on this distribution's shape.
In a psychological study where a distribution of scores is highly skewed by a single extreme outlier, the mean is a more valid descriptive statistic than the median for evaluating the typical performance of the sample.
Measures of dispersion, such as the standard deviation and variance, are descriptive statistics used to describe the average scores within a research sample.
Tables in Research Reports
A psychologist studies the sleep patterns of college students and wants to summarize the collected data. Why must the psychologist report both a measure of central tendency (such as the mean) and a measure of dispersion (such as the standard deviation) to provide a complete descriptive summary of the sample's sleep duration?
A researcher records the number of errors made by five participants on a memory task: 3, 8, 2, 5, and 7. The range for this sample is _____.
A research team is summarizing data from a psychology study. Match each descriptive statistic on the left to the research situation on the right where it would be the most appropriate single summary to report.
A researcher reports that two groups of participants completed an identical mood-rating scale (scored 0–100). Group A had a mean of 60 and a standard deviation of 4, while Group B had a mean of 60 and a standard deviation of 22. Although both groups share the same measure of central tendency, a student analyzing these results should conclude that Group B's scores show substantially greater _____ than Group A's scores.
A researcher has collected scores on a stress questionnaire from 80 undergraduate participants and must decide which descriptive statistics to select and report. Arrange the following evaluative steps in the order that best supports an accurate, justified statistical summary of the data.
Define descriptive statistics and identify the two primary categories of quantitative techniques described in the text, including the specific measures associated with each.
Based on the case context, decide how the researcher should apply descriptive statistics to describe their data. Explain the two different types of measures the researcher needs to calculate and specify what each type of measure will communicate about the sample's performance.
A psychological researcher reports that a sample of participants completed a stress assessment, resulting in a mean score of and a standard deviation of . Explain what these specific descriptive statistics indicate about the scores of the participants in this sample.
Cohen's