Personality

In this applet, you’ll expand on your knowledge of research design, specifically longitudinal studies, and the concept of standard error (defined in the first Statistical Lesson) and the impact of the size of the sample.

Question 1

Question 1, In the National Survey of Midlife Development, participants’ personalities were measured in 1995-1996 and again 9 years later in 2004-2005. How do the scores compare over time for neuroticism? (Pick “Neuroticism” for the group.)

Scores were very similar from the first measurement to the second, with similar averages and range of scores.

Scores were much larger in the first measurement than in the second, with a larger average score but a more narrow range of scores.

Scores were much smaller in the first measurement than in the second, with a smaller average but a more narrow range of scores.

Scores were very similar from the first measurement to the second, but a larger average and range of scores in 2004-2005.

Question 2

Question 2, Compare the graph obtained in question 1 to when agreeableness is chosen. How do the two graphs differ? (Pick “Agreeableness” for the group.)

Scores for these personality traits remained consistent over time, but agreeableness had larger averages and a smaller range of scores.

Scores for these personality traits remained consistent over time, but agreeableness had larger averages and a larger range of scores.

Scores for these personality traits had similar averages and range of scores.

Scores for these personality traits remained consistent over time, but neuroticism had larger averages and a smaller range of scores.

Question 3

Question 3, Is there a pattern evident in all of the personality traits over time? (Cycle through the various traits for the group, making a note of the range of scores and averages.)

Though some traits had smaller averages or range of scores than others, scores for individual traits were fairly consistent from 1994-1995 to 2004-2005.

Some traits had consistent scores while other traits had scores that decreased drastically from 1994-1995 to 2004-2005.

Though some traits had smaller averages or range of scores than others, scores for individual traits typically increased drastically as individuals aged from 1994-1995 to 2004-2005.

Though some traits had smaller averages or range of scores than others, scores for individual traits typically decreased drastically as individuals aged from 1994-1995 to 2004-2005.

Statistical Lesson:

Our goal with most statistics is to make guesses about the population using what we learn from a sample. When we calculate the sample mean or average, we can also determine how close this average might be to the actual population average. We estimate this via the standard error, which is how much our sample average deviates from the population average. If the standard error is small, then we are more confident that the sample average is closer to the population average. However, if the standard error is large, then we are less confident that our sample can accurately predict the population average. Since our goal is typically to make assumptions about the population using the sample, then it is best to reduce the size of our standard error.

The sample size is important because the larger the sample, the better it reflects the population. Smaller data sets can have high levels of variability and may be misleading. Fortunately, we don’t necessarily need to sample everyone or everything in the population. Moderately sized data sets are typically sufficient and more realistic to achieve.

Question 4

Question 4, In the graphs displayed for questions 1-3, the bars extending outside from the mean give us the standard error. Which traits had the largest errors? (Cycle through the various traits for the group, making a note of the averages and standard error.)

Neuroticism and agreeableness.

Conscientiousness and agreeableness.

Agency and agreeableness.

Agency and neuroticism.

Question 5

Question 5, Reference again the bars signifying standard error extending outside from the mean in the graphs displayed for questions 1-3. Which traits had the smallest errors? (Cycle through the various traits for the group, making a note of the averages and standard error.)

Agency and agreeableness.

Agency and neuroticism.

Neuroticism and agreeableness.

Conscientiousness and agreeableness.

Question 6

Question 6, Evaluate the impact of sample size on the variability in scores and standard error. What appears to be the relationship between the sample size and these concepts? (Cycle through the various traits for the group while selecting different sizes for the Sample Size. Make a note of the averages and standard error.)

As the sample size increases, the variability in scores and standard errors increase.

As the sample size increases, the variability in scores increases and standard errors decrease.

As the sample size increases, the variability in scores and standard errors decrease.

As the sample size increases, the variability in scores and standard errors remain the same.

Question 7

Question 8

Question 8, Does the data analyzed in this applet support the information in the text about personality over time?

The findings contradict the text since we found that our personality is stable over time with some change possible in adulthood, though it is typically small. The text implies that our personality is extremely flexible, with major changes possible in adulthood.

The findings support the text, our personality is extremely flexible over time with major change possible in adulthood.

The findings contradict the text since we found that our personality is extremely flexible over time with major change possible in adulthood. The text implies that our personality is stable, with some changes possible in adulthood, though it is typically small.

The findings support the text, our personality is stable over time with some change possible in adulthood, though it is typically small.