# Dating strategy optimisation by the analysis of trends from an internet dating site

Here I demonstrate a strategy both men and women can use to maximise the probability of dating success. The investigation also characterises behaviour exhibited by men and women which explain the phenomena of male mid life crisis and can also provide an estimate of relationship longevity.

A popular dating site in the UK lists the ages of the subscribers and the highest and lowest age of the partner that they are interested in. The initial motivation for this project was to discover the optimum age that should be targeted to maximise chances of dating success. However, during the investigation, patterns in the data were observed that could explain the phenomenon of the male mid-life crisis and predict when it is likely to occur for a particular individual. This knowledge could be used to reduce the impact of this difficult period by giving everyone involved adequate time to prepare, or exploited by marketing companies hoping to sell more convertible sports cars.

### Data source

This particular dating site was chosen because each user’s record contains their age (a), and the maximum and minimum age of the partner they are looking for (h and l respectively). This age range is referred to as the ‘desired age’ in this discussion. The site is arranged in such a way that this data can be gathered automatically using a Perl script and saved in a tab-delimited text file. From there it can be loaded into most data analysis software packages. Only the three parameters described above were recorded and no personal data was gathered. An example of the data is given in Table 1.

a |
l |
h |

23 | 24 | 31 |

32 | 28 | 37 |

35 | 30 | 45 |

… | … | … |

Table 1: Example data

### Calculating the desired age range of individuals

500 samples for each age between 20 and 50 were taken of males and females . Towards the extremes of the age range 500 samples were not always available. The average of *h* and *l *were taken and the results plotted. These are shown in Figures 1 and 2. The red dots are the average high limit and the blue dots are average low limit for each age. The dots form an almost perfect straight line. The solid red and blue lines are the best fit lines through the data points. These graphs allow an insight into how the ages of partners that males and females are attracted to changes over time.

The graphs can be interpreted as follows. To determine the age range that a person desires, look up their age on the x-axis. Draw a vertical line from here and at the intersections with the low and high limit lines read off the corresponding ages on the y-axis. For example, from Fig 1 the average desired age range for a 30-year old man is between 24 and 32. Working backwards, to find the ages of women who are attracted to 30 year old men, locate 30 on the y-axis of Fig 2 and draw a horizontal line. At the intersections with the low and high limit lines read off the corresponding ages on the x-axis. In this case the range is about 22 to 32. A function to calculate the optimum age range to target when dating is given here.

### Evaluation of the ‘half your age plus seven’ rule

The ‘half your age plus seven’ rule has long been cited as the minimum age of a woman that a man should date. Fig 4 below shows this rule overlayed on the female desired age chart. As can be seen, this will only be a successful tactic for men aged below about 28, and even then will be far from the optimum value. A more accurate, if less catchy, rule of thumb would be ‘age minus seven, times one point one seven’.

### Observations

These graphs reveal several phenomena:

**Range of desired age increases with age**

The red and blue lines are not parallel and diverge over time for both sexes. While a 25 year old woman will desire a man aged between about 25 and 33 (a range of 8 years), a 45 year old woman will desire a man between about 40 and 52 (a range of 12 years). A similar pattern is seen in the data for males. Basically everyone gets less choosy the older they get.

**Desired age range differs between genders**

The solid green line shows the path followed by a partner the same age. This makes it easier to visualise the desired age of a potential partner in relation to one’s own age. From this it can be seen that in general, women are attracted to men older than themselves, while men are attracted to younger women. This corresponds well with anecdotal evidence and it is nice to see it confirmed by the data.

**Partners may lose attraction over time**

The high and low age limits for each sex increase at less than 1 year per year (the gradient of the lines are less than 1). This means that as people age, they will traverse the desired age range of their partner. For a couple who met when they were both within each other’s desired age range, one of the partners will move out of the other’s desired range at some point in the future. For example, let us suppose that a 30 year old man has a 30 year old partner. The partner’s point in the male’s desired age range is now shown by the green line in Fig 1. As time passes, the green line moves closer to the high age limit until it intersects with it when the couple are aged about 46. Beyond this point, while the male is still well within the female’s desired age range (Fig 2) the female is now outside the male’s desired age range suggesting that the male will begin to lose interest and start looking for a younger female. This observation will now be developed in the following section.

### Prediction of relationship longevity

The high and low limit lines from each graph can be represented by an equation of the form:

Where m is the gradient of the line and c is its intersection with the y-axis.

To discover the age at which one partner (p) will lose interest in the other partner (q) we must calculate the intersection of the high limit line of partner p and the line traced by partner q’s age. The line traced by partner q’s age has the parameters m=1 and c=Δa, where Δa is the difference in age between p and q (Δa=q-p). Intersection occurs when:

Solving for x gives:

Using the line parameters in Appendix A, the ages at which a particular couple will be attracted to each other can be calculated. This calculation has been implemented in a web page and can be seen here.

### Relationship to male mid-life crisis

In the case of females, the point of intersection between their high age limit and the age of a similarly aged partner occurs when the couple are about 146 years old. This seldom occurs except in some Old Testament couples. For males however, this will occur when the couple are about 46 years old. This coincides with the general age of the onset of the male mid-life crisis and may account for some of the behaviour exhibited by men during this period. A mid-life crisis calculator has been developed and can be seen here.

### Determining partner compatibility

As discovered above, what you want and what you can get are two different things. Fig 5 shows the male and female desired age ranges plotted as areas on the graph. The intersection of the red and blue areas shows where mutual attraction occurs between the sexes. It is in this area that reproductive effort should be put to maximise the chance of success. Print out this chart and take it to the next party you go to.

**Appendix A: Line parameters**

**Appendix A: Line parameters**

The parameters for the lines in Figures 1 and 2 are given below:

m | c | |

Male low limit | 0.6235 | 5.0147 |

Male high limit | 0.8367 | 7.5663 |

Female low limit | 0.7758 | 4.9411 |

Female high limit | 0.9396 | 8.8608 |

Table 2