Quanty Exam II

What is the advantage of using SPSS over calculating statistics by hand?

c) It equips you with a useful transferable skill

Given a test is normally distributed with a mean of 30 and a standard deviation of 6: What is the probability that a single score drawn at random will be greater than 34?

0.2524

The owner of the large chain of coffee shops called 'MoonBucks' decided to calculate how much revenue was gained from lattes each month in a nationwide sample of 2445 cafés. To measure the variance of revenue gained from lattes, he computes SS = 351,936 for this sample. What are the degrees of freedom for variance? Compute the variance. Compute the standard deviation.

2444

Twenty-one cats were given 300g of tuna each. The time in seconds was measured until they had eaten all of the tuna: 16, 18, 18, 22, 22, 23, 23, 24, 26, 29, 32, 34, 34, 36, 36, 42, 43, 46, 46, 49, 57 Compute the median. Compute the lower quartile. Compute the upper quartile. Compute the interquartile range.

32 seconds

If Pearson's correlation coefficient between stress level and workload is .8, how much variance in stress level is not accounted for by workload?

36%

Rank the score of 5 in the following set of scores: 9, 3, 5, 10, 8, 5, 9, 7, 3, 4

4.5

How much variance has been explained by a correlation of .9?

81%

Which of the numbers below might IBM SPSS report as 8.96 E+03?

8960

Out of the following options, which type of bar chart would we produce to look at the mean ratings of 'taste' and 'value for money' for two new varieties of Sauvignon Blanc wine?

All of the above (Clustered Bar chart, Stacked Bar chart, 3-D Bar Chart)

The covariance is:

All of the above (measure of strength, Dependent on units of measurement, unstandardized version of the correlation coefficient)

Which of the following best describes the variable 'Gender'?

All of the above(grouping,between-group,coding)

When items on a questionnaire appear to correspond to the construct that the questionnaire claims to measure it is said to have:

Content Validity

Ordinal level data are characterized by:

Data that can be meaningfully arranged by order of magnitude

What is an outlier?

EXTREME VALUE When we calculate a simple average, the 'arithmetic mean', we have to remember that a wide range of values can give the same average as a narrow range and that extreme values could make a simple average fairly meaningless. These values are called 'outliers', extremely high or low values in a distribution that threaten to bias the results. The 'median' is useful, in this regard, because it simply identifies the mid-point in a whole array of values, giving us a measure of the significance of the arithmetic mean.

For what is the 'variable view' in IBM SPSS's data editor used?

Entering Data

The degree to which a statistical model represents the data collected is known as the:

Fit

If we calculated an effect size and found it was r = .42 which expression would best describe the size of effect?

Medium to Large

An experimenter measured 30 children's IQ. He then rank-ordered the children and assigned them a score from 30 (most intelligent) to 1 (least intelligent) to create a new variable. Does this new variable consist of:

Ordinal data

Out of the following options, which type of bar chart would we produce to look at the mean ratings of two new varieties of Sauvignon Blanc (wine)?

Simple bar chart

If we use the mean as a model, what does the variance represent?

The average error between the model and the observed data

What is the difference between interval/ratio and ordinal variables?

The distance between categories is equal across the range of interval/ratio data

What type of graph can we use to compare frequency distributions of several groups simultaneously?

a population pyramid

How would you print a bar chart that you have just produced in SPSS?

a) In Output Viewer, click File, Print, select the bar chart and click OK

How is a variable name different from a variable label?

a) It is shorter and less detailed

If there were a perfect positive correlation between two interval/ratio variables, the Pearson's r test would give a correlation coefficient of:

b) +1

In SPSS, what is the "Data Viewer"?

b) A spreadsheet into which data can be entered

How would you use the drop-down menus in SPSS to generate a frequency table?

b) Click on: Analyze; Descriptive Statistics; Frequencies

In which sub-dialog box can the Chi Square test be found?

b) Crosstabs: Statistics

What is the function of a contingency table, in the context of bivariate analysis?

b) It summarises the frequencies of two variables so that they can be compared

Setting the p level at 0.01 increases the chances of making a:

b) Type II error

What is meant by a "spurious" relationship between two variables?

c) A relationship that appears to be true because each variable is related to a third one

What does the operation "Recode Into Different Variables" do to the data?

c) Redistributes a range of values into a new set of categories and creates a new variable

When cross-tabulating two variables, it is conventional to:

c) Represent the dependent variable in rows and the independent variable in columns

What is the difference between a bar chart and a histogram?

c) There are no gaps between the bars on a histogram

When might it be appropriate to conduct a multivariate analysis test?

d) All of the above

To generate a Spearman's rho test, which set of instructions should you give SPSS?

d) Analyze; Correlate; Bivariate; [select variables]; Spearman; OK

A test of statistical significance indicates how confident the researcher is about:

d) Generalizing their findings from the sample to the population

Why might you tell SPSS to represent the "slices" of a pie chart in different patterns?

d) If you do not have a colour printer, it makes the differences between the slices clearer

What is the relationship between the sum of squared errors (SS), the sample size (n) and the variance (s2)?

n=(s2-ss)-1

Out of the following options, which type of graph could we use to compare frequency distributions of several groups simultaneously?

population pyramid

Which of the following does a box-whisker plot not display?

Mean

Variation due to some genuine effect is known as:

Systematic Variation

What is the name of the test that is used to assess the relationship between two ordinal variables?

a) Spearman's rho

Which of the numbers below might IBM SPSS report as 10.574 E−05?

.00010574

A correlation of .7 was found between time spent studying and percentage on an exam. What is the proportion of variance in exam scores that can be explained by time spent studying?

.49