Calculation of Mixture Statistics Using Popstats - Promega

More documents

Recommendations

Info

Lets look at a different scenario Often you may have evidence that presents a mixture and a suspected contributor… The question would be: What is the likelihood <strong>of</strong> the suspect being a contributor to the evidentiary pattern?
Suspect Evidence A 1 A 2 A 1 A 2 A 3 A 4 Four Allele Scenario
Page 1 and 2:
Popstats Unplugged 14 th Internatio
Page 3 and 4:
What Constitutes a DNA Mixture? Pr
Page 5 and 6:
What Constitutes a DNA Mixture? Ci
Page 7 and 8:
Common Mixture Interpretations Alle
Page 9 and 10:
But, before we begin… Calculation
Page 11 and 12:
Two common questions are generally
Page 13 and 14:
Exclusion Probability This is a mea
Page 15 and 16:
For example: Exclusion Probability
Page 17 and 18:
Exclusion Probability The probabili
Page 19 and 20:
Exclusion Probability In presence o
Page 21 and 22:
Exclusion Probability What does thi
Page 23 and 24:
We have the following data: Mixture
Page 25 and 26:
Given that both victim and suspect
Page 27 and 28:
What if we couldn’t assume H-W? P
Page 29 and 30:
How does PopStats handle this calcu
Page 31 and 32:
Here is the input data But what is
Page 33 and 34:
It is the compliment of Inclusion P
Page 35 and 36:
PE = 1 - 8.033 X 10 -7 = 0.99999919
Page 37:
What if we have to consider some al
Page 40 and 41:
Mixtures and Likelihood Ratios Like
Page 42 and 43:
Let’s use the same example used i
Page 44 and 45:
Three Alleles Victim is heterozygot
Page 46 and 47:
The prosecution may postulate that
Page 48 and 49:
The defense might argue that the fo
Page 50 and 51: The defense might argue that the fo
Page 52 and 53: Since the victim has the profile (8
Page 54 and 55: Now here is where the “RATIO” i
Page 56 and 57: Defense hypothesis 2 is a little mo
Page 58 and 59: How do we get these probabilities?
Page 60 and 61: Of course…we could incorporate θ
Page 62 and 63: What next… The total probability
Page 64 and 65: HOW TO EXPRESS THE NUMBERS FROM LIK
Page 66 and 67: Conservative Basic True!
Page 68 and 69: Or The probability (chance) that th
Page 70 and 71: Assumptions In Likelihood Computati
Page 72 and 73: Assumptions In Likelihood Computati
Page 74 and 75: So, lets go back to our previous da
Page 76 and 77: And our "K1" and "K2" genotypes:
Page 78 and 79: Our entry data from before:
Page 80 and 81: This side will autofill when changi
Page 82 and 83: C2 reflects the H a H a = The resul
Page 84 and 85: Notes: • The layout screen is pos
Page 86 and 87: Ok… so what do we get when we pus
Page 88 and 89: Big Number Names: • 1,000,000 mil
Page 90 and 91: You could also look at what the all
Page 92 and 93: C2 reflects the H a H a = The resul
Page 94 and 95: You can drag and drop the entire fi
Page 96 and 97: Continue, holding the SHIFT button
Page 98 and 99: Big Number Names: • 1,000,000 mil
Page 102 and 103: Two alleles match the suspect - A 1
Page 104 and 105: The prosecution may postulate that
Page 106 and 107: The defense might argue that the fo
Page 108 and 109: The resulting likelihood ratio is:
Page 110 and 111: So, with regard to Defense Hypothes
Page 112 and 113: Same question as before but… Thre
Page 114 and 115: Under the Prosecution’s hypothesi
Page 116 and 117: Unk 1 Unk 2 A1A2 A1A2 A1A2 A1A3 A1A
Page 118 and 119: The Likelihood Ratio becomes: p 3 2
Page 120 and 121: p 1 = 0.1, p 2 = 0.2, and p 3 = 0.3
Page 122 and 123: So, with regard to the Defense Hypo
Page 124 and 125: Of course we can do this in PopStat
Page 126 and 127: Of course we can do this in PopStat
Page 128 and 129: Now…Let's have some real fun! Sce
Page 130 and 131: Our Knowns: Let's see how this scen
Page 132 and 133: H a1 = The results are explained by
Page 134 and 135: Our Results:
Page 136 and 137: The "profile" in C1 represents all
Page 138 and 139: Our Results:
Page 140 and 141: Considerations Unlike interpretatio
Page 142: Considerations Most critical step o
show all

Calculation of Mixture Statistics Using Popstats - Promega

Create successful ePaper yourself

Delete template?

Save as template?