The objective: The purpose of my science fair project is to determine whether fingerprints are hereditary, which types are hereditary, and which parent to child combination is most hereditary.
Collecting data: look at fingerprints or ink the fingerprints. Label using ten types: left loops(LL), left pocket loops (LPL), right loops (RL), right pocket loops(RPL), central pocket loops(CPL), double loops(DL), arches(A), tentarches(TA), whorls(W), and accidentals(X).
A family must have a father (F), mother (M), and at least 1 child (daughter-D or son-S). For analyzing data, a scientific calculator and a z-test distribution table are necessary.
For generating random families, generate random numbers with the calculator to assign each individual to a new family. Maintain family composition (if a family has two daughters, the new random family in its place should have two daughters).
To create a proportion r (null hypothesis), take e.g. the of sons prints that are LL and divide it by the total of sons prints. Create a second proportion p the sample statistic the of sons prints that are LL where the fathers print was also an LL divided by the of sons prints that are LL. Next, calculate the standard deviation (SD) of the second proportion.
Use SD= the square root of [p(1 - p) /n], where n is the of sons. To calculate the Z-statistic, use [Z =(p r)/SD].
Next, calculate the same for the of sons prints that are LL where the Ms print was also an LL divided by the of Ss prints that are LL.
Do the same for all 10 types of prints. Repeat for S-M, D-F, and D-M. With the Z-test, use a confidence level of 95%.
In all, there were 15.2 average matches from all the real categories, and 10 average matches from all the random categories.
LL, As, and TAs were shown to be hereditary in all four parent to child comparisons.
LPL and PL were shown to be hereditary in three of the parent to child comparison groups. RPL, CPL, and Ws were shown to be hereditary in two of the comparison groups.
DLs could only be shown hereditary in one group. Accidentals were not shown to be hereditary in any of the groups..
My hypothesis was correct in that fingerprints are hereditary and that in my sample, the Ss to Fs were the most hereditary, but I was incorrect because I couldnt show that all the types I evaluated were hereditary and Ds to Ms was not the most hereditary group.
This project determined whether fingerprints are hereditary, which types are hereditary, and which parent to child combination is most hereditary using a z-test and other statistical methods