Spss political analysts

Assignment # 1

1.

Median = 40.57

Middle value after arranging all turnovers in ascending order. Since even number of data points, median is the average of two middle values, 7th and 8th in this case.

Median is not affected by outliers hence it is a better indicator of general values. In our group of 14 countries, we can suggest that the typical value of turnover is 40.57% in the 2014 elections.

Mean = 45.19

Mean is the average central value suggesting that approximately there is a 50% chance or probability that if we pick a country at random, its turnout for the 2014 elections will be 45.19% of total population.

Range = 65.81

This is quite a large range suggesting that our data is widely distributed or dispersed. The difference between the countries with the largest and smallest turnout in 2014 election is 65.81.

MAD = 13.71

Mean Absolute Deviation (MAD) indicates the variability in a data set. Hence a MAD of 13.71 means that on average, each value of turnover was 13.71 away from the mean turnover value of all 14 countries.

2. The expected skew of my distribution is towards right side, that is positive skew since the median is smaller than the mean. The more number of high turnovers pull the mean more towards right than the than the median resulting in results calculated above.

3. Closed System

Median = 39.71

Middle value after arranging all turnovers in ascending order. Since even number of data points, median is the average of two middle values, 2nd and 3rd in this case.

Median is not affected by very large or very small values hence it is a better indicator of general values. Out of 14 countries, 4 countries had a closed party list and for those 4 countries we can suggest that the typical value of turnover is 39.71% in the 2014 elections.

Mean = 40.30

Mean is the average central value suggesting that approximately there is a 50% chance or a probability of 0.5 that if we pick a country at random out of the 4, its turnout for the 2014 elections will be 40.30% of total population.

Range = 14.43

This is narrow range suggesting that our data is squeezed and narrowly distributed. The difference between the closed system countries with the largest and smallest turnout in 2014 election is 14.43.

MAD = 5.66

Mean Absolute Deviation (MAD) indicates the variability in a data set. Hence a MAD of 5.66 means that on average, each value of turnover was 5.66 away from the mean turnover value of the 4 countries with closed system.

Skew: The mean is slightly higher than the median value which means higher numbers have pulled the mean slightly on the right hence a positive skew is expected.

Preference System

Median = 41.36

Middle value after arranging all turnovers in ascending order. Since even number of data points, median is the average of two middle values, 5th and 6th in this case.

Median is not affected by outliers hence it is a better indicator of general values. In our group of 14 countries, 10 had some kind of preference system and for those 10, we can suggest that the typical value of turnover is 41.36% in the 2014 elections.

Mean = 47.15

On average 47.15% of population have voted amongst the 10 countries with preference system. Mean is the average central value suggesting that approximately there is a 50% chance or probability of 0.5 that if we pick a country at random, its turnout for the 2014 elections will be 47.15% of total population.

Range = 65.81

This is a wide range suggesting that 10 countries turnover is widely distributed or dispersed. The difference between the countries with the largest and smallest turnout of those 10, in 2014 elections is 65.81.

MAD = 17.01

Mean Absolute Deviation (MAD) indicates the variability in a data set. Hence a MAD of 17.01 means that on average, each value of turnover was 17.01 away from the mean turnover value of the 10 countries with preference system.

Skew: The mean is again higher than the median value which means higher numbers have pulled the mean slightly on the right hence a positive skew is expected.

4. Summary of Results

The averages are all calculated as above and we can see that the medians for all 14 countries with mail ballot, for 4 amongst them with closed party and for the other 10 with preference system are 40.57, 39.71 and 41.36 respectively. Similarly, the means are 45.19, 40.30 and 47.15 in the same order. All of these indicate that most countries lie below the average turnover.

The whole group of 14 countries and the 10 with preference have the same range of 65.81 while the 4 countries with closed system have a spread of 14.43. This indicates that the closed system countries turnover is more reliable or more close together. Almost same amount of people come out to vote. On the other hand the other two groupings have large ranges and hence scattered data. In some countries people vote in large numbers while in some the turnout is very low. The MADs are 13.71, 5.66 and 17.01 respectively which clearly show us that countries with closed system have reliable turnouts and forecasting can be done with better results however the other 10 countries have a very large MAD showing unreliable turnout or larger deviations from the mean turnout of 2014 elections. The graps were plotted which showed a negative skew that is leaning towards right which was opposite of what we expected from the mean/median comparison. This is not an error because many a time the skewness is not directly related to the mean and medians. The Data set is negatively skewed!