## STATISTICAL GRAPH

The title of each graph of the statistical study indicates the **parents variables (R or M & F)** to which the correlations are related. These correlations are represented by each point of the coloured lines corresponding to each examined **C** variable (**children**).

Likewise, the variables of unknown order, formed by the different **groups** of 1 to 10 **values** from the 70 **IQ values** of each parent and children variables are placed on the left hand side of the graph. The groups of 1 to 10 values located on the right hand side have been previously ordered with the variable mentioned at the bottom of the graph.

Indeed, an almost instantaneous perception of the exactitude of the particular specification of the statistical study is obtained; sixty **coefficients of determination** (r²) are shown in a way that highlights the global and underlying relations of the involved data set.

**See the methodology of the statistical abstract for more details**

## STATISTICAL STUDY COMMENTS

## 1. General statistical significance

The great increase of the correlation for the estimation of **homogenous groups** cannot be imputed to the reduction of 68 to 5 or 4 degrees of freedom, since the estimation with non-homogenous groups, without previous rearrangement, has the same degrees of freedom and the correlation even lowers with respect to the sample without grouping.

When the model of the statistical study has more freedom with the two intelligence quotients' variables, **M** and **F,** either it definitely adjusts better by statistical effect or the statistical data set we have available is a particular case.

In general, the model of genetic evolution of intelligence (*Mendelian genetics – Conditional intelligence – Gobal Cognitive Theory*) adjusts perfectly, showing an **r² **superior to 0.9 in several cases. Bearing in mind the tendency to increase the goodness of fit with the size of rearranged groups, we could asume it would be **over 0,9 in almost all the cases **for groups bigger than 20, of course, it should be needed a bigger sample.

## 2. *Family* - Intelligence of identical and non identical twins.

Family relationships are very interesting regarding genetics and intelligence, in fact, the whole EDI study is related to family characteristics.

Some research can be done regarding relations of identical twins, non identical twins, clones and even the effect of intelligence while selecting a partner or sexual selection.

Actually, we know that all **C** variables correspond to mono-environmental identical twin brothers, whereas **W** will only be a sibling; for that reason, sometimes they will look alike and others not so much.

It does not seem hard to imagine some interesting studies on these peculiar matters.

For instance, the selection of a partner as an auxiliary mechanism of evolution has been a paradigm since the first developments of the theory of evolution. **Darwin** himself wrote The *Descent of Man and Selection in Relation to Sex* (1871) introducing a new factor, **sexual selection,** through which females or males choose those with the most attractive qualities as their partner.

## 3. Statistical significant figures of this particular graph

Similarity of variable C's behaviour in the 0r81-twins.html graph can be interpreted in the sense that the coefficients could correspond to **identical twins** whereas the **W** would only be a **normal sibling** since it has been generated with the data of the same parents.

This performance can be found on numerous occasions when the rearrangement criterion is one of the C variables.

In the case shown in the 0r82-twins.html graph, **W** is used as the criterion of arrangement, and the behaviour is slightly different; it seems that the four variables correspond to **identical twins.** This is, of course, a particular case.

Actually, we know that all **C** variables correspond to *mono-environmental identical twin brothers,* whereas **W** will only be a sibling; for that reason, sometimes they will look alike and others not so much.

It does not seem hard to imagine some interesting studies on these peculiar matters.