PSYC 104 CH 05

When wishing to report the variability associated with an ordinal variable, we can communicate:

Minimum & maximum value and the 25th & 75th percentile

How long are these people working since they were hired? Below is an analysis of the respondents' data using SPSS.Which of the four written reports, according to the Workbook, provides the appropriate information? Note that the scale of measurement for is 'scale.'

Most people have worked for the company for several years (m = 81.11 months, s = 10.06 months).

The measure(s) of central tendency to report for scale data depends upon ________________.

The measure(s) of central tendency to report for scale data depends upon the shape of the distribution and whether there are any outliers. If the distribution is normal, and there are no outliers, then the mean should be reported. If the distribution is definately not normal, or there are outliers, then report the median. This is because the median is not affected by outliers, and is less affected by skewed distributions than the mean.

What is the average life expectancy for women in the world? For every country, there is published data on average life expectancy. The SPSS analysis of average life expectancy for women was based on the data for 109 countries in the world.Which of the four written reports, according to the Workbook, provides the appropriate information? Note that the scale of measurement for age is 'scale.'

The scale of measurement for women's life expectancy is scale. This means that there are equal intervals, allowing us to use a histogram graph (instead of a bar graph).When looking at the histogram, if the distribution is strongly skewed, as it is in this case, then you should report the median (abreviated as mdn) and the IQR. This is because the mean and standard deviation would be less 'truthful' concerning what is typical... they would be pulled in the direction of the tail of the distribution.

How exciting do people find life? Below is an analysis of the respondents' data using SPSS.Which of the four written reports, according to the Workbook, provides the appropriate information? Note that the scale of measurement for "Is life Exciting or Dull" is 'ordinal.'

The scale of measurements for the variable is ordinal. For ordinal data, we report the median (the middle value in the data set). We can not calculate a range for ordinal data - we can not add or subtract since there are not equal sized intervals. So to communicate the variability in responses, we report the minimum value and the maximum value. We also report the 25th percentile and 75th percentile (i.e., the minimum and maximum for the middle 50% of the data).

When wishing to report the variability associated with a nominal variable, we can communicate:

When wishing to report the variability associated with a nominal variable, we can communicate the number of diffent responses that were made. This is because nominal data represents categories that cannot be ranked.... so the best you can do is at least let the reader know how many different responses were made. So if the responses to political party were (democrat, democrat, independent, republican, other, independent, republican, republican), then there were four different responses made.

To evaluate whether a variable is normally distributed, we can look at whether:

all the answers are correct The histogram looks approximately normal Mean ≈ Median ≈ Mode

The measure(s) of central tendency to report for nominal data ________________.

is the mode

When the variable is scale, the distribution is fairly normal, and there are no outliers, then we should report the ________________ as the measure of central tendency and the ________________ as the measure of dispersion.

mean; standard deviation

The measure(s) of central tendency to report for nominal data ________________.

mode

For the ideal normal distribution

the curve is symmetrical all of the answers are correct the mean, median, and mode are all equal the curve is bell shaped

The measure(s) of central tendency to report for scale data depends upon ________________.

the shape of the distribution and whether there are any outliers