Homework Exercise

1.    
Define the following terms:

 

·        
Descriptive statistics

·        
Scales of measurement

·        
Measures of central tendency

·        
Frequency distributions

·        
Correlation coefficient

·        
Effect size

·        
Multiple regression

 

2.    
How are group means, percentages, and
correlations used to describe research results?

 

 

3.    
How can graphs be used to describe and summarize
data?

 

 

4.    
A researcher is studying reading rates in
milliseconds per syllable. What scale of measurement—nominal, ordinal,
interval, or ratio—is time in milliseconds? Explain your response.

 

5.    
Under what circumstances is the median or mode a
better measure of central tendency than the mean? Explain your response.

 

6.    
True or false: The standard deviation and the
range are sensitive to outliers. Explain your response.

 

7.    
True or false: The standard deviation can never
be 0. Explain your response.

 

8.    
A researcher is investigating the effects of anxiety
on creativity. Individuals with varying levels of anxiety are asked to complete
a measure of creativity. The results show a classic U-shaped distribution; that
is, individuals with moderate levels of anxiety score the highest on tests of
creativity. Individuals with very low or very high levels of anxiety score much
lower on tests of creativity. What would be a good statistic to use in this
case? Explain your response.

 

9.    
What are some applications of multiple
regression models (equations / techniques)? Provide an example.

 

10. 
Explain how and why multiple correlations are
used as prediction variables?