Question

A psychologist would like to examine the effects of prior expenence on learning a

new task Two sample groups of rats were compared. One group had participated in a
variety of learning experiments over the past 4 months, and the other group had just
arrived at the psychology department with no prior research experience. All the rats
were tested on a discrimination learning problem and the psychologist recorded the
number of errors each animal made before it solved the problem- The data are as
follows: (55 pts.)
Experienced rats:
7, 8, 9, 10, 9, 7, 9, 8, 7.10.8, 9, 9, 6, 9, 6, 12, 11
Inexperienced rats:
11, 122 11, 10, 10, 12. 13. 10, 13, 9. 10, 11, 13: 12, 142 122 10, 10, 10
a.
b.
c.
d.
Construct a simple frequency table for each group (18 pts)
Be sure to include the following statistics in the table: (1) Simple frequency,
(2) relative frequency, (3) percentage frequency, (4) cumulative frequency, (5)
cumulative relative frequency, and (6) cumulative percentage frequency.
Sketch a histogram showing the distribution of scores for each group (two
separate graphs; 6 pts).
Find the mean: median, and mode for the data from each of two groups ofrats
(12 pts).
Find the range: variance; and standard deviation of the data from each group
of rats (19 pts).

Answer 1

To construct a frequency table for the two groups, we count the number of times each value appears and calculate the relative and cumulative frequencies. The histograms show the distribution of scores for each group. The mean, median, mode, range, variance, and standard deviation are calculated for both groups.

Step-by-step explanation:

To construct a simple frequency table for each group, we need to count the number of times each value appears in the data. Then, we can calculate the relative frequency, percentage frequency, cumulative frequency, cumulative relative frequency, and cumulative percentage frequency. Here is the frequency table for each group:

Experienced Rats:

Value - Simple Frequency - Relative Frequency - Percentage Frequency - Cumulative Frequency - Cumulative Relative Frequency - Cumulative Percentage Frequency

6 - 2 - 0.125 - 12.5% - 2 - 0.125 - 12.5%

7 - 3 - 0.1875 - 18.75% - 5 - 0.3125 - 31.25%

8 - 2 - 0.125 - 12.5% - 7 - 0.4375 - 43.75%

9 - 6 - 0.375 - 37.5% - 13 - 0.8125 - 81.25%

10 - 3 - 0.1875 - 18.75% - 16 - 1.0 - 100%

11 - 2 - 0.125 - 12.5% - 18 - 1.125 - 112.5%

12 - 1 - 0.0625 - 6.25% - 19 - 1.1875 - 118.75%

Inexperienced Rats:

Value - Simple Frequency - Relative Frequency - Percentage Frequency - Cumulative Frequency - Cumulative Relative Frequency - Cumulative Percentage Frequency

9 - 2 - 0.1111 - 11.11% - 2 - 0.1111 - 11.11%

10 - 6 - 0.3333 - 33.33% - 8 - 0.4444 - 44.44%

11 - 5 - 0.2778 - 27.78% - 13 - 0.7222 - 72.22%

12 - 4 - 0.2222 - 22.22% - 17 - 0.9444 - 94.44%

13 - 2 - 0.1111 - 11.11% - 19 - 1.0 - 100%

Histogram:

Mean, Median, and Mode:

For the Experienced Rats:

Mean = 8.5625

Median = 8.5

Mode = 9

For the Inexperienced Rats:

Mean = 10.1667

Median = 10

Mode = 10

Range, Variance, and Standard Deviation:

For the Experienced Rats:

Range = 6

Variance = 2.5166

Standard Deviation = 1.5854

For the Inexperienced Rats:

Range = 4

Variance = 1.9139

Standard Deviation = 1.3822