Question

Fingerprint expertise.A study published in PsychologicalScience(August 2011) tested the accuracy of experts andnovices in identifying fingerprints. Participants were presentedpairs of fingerprints and asked to judge whetherthe prints in each pair matched. The pairs were presentedunder three different conditions: prints from the same individual (match condition), non-matching but similar prints (similar distracter condition), and nonmatching and very dissimilar prints (non-similar distracter condition). The percentages of correct decisions made by the two groups under each of the three conditions are listed in the table.

Conditions	Fingerprints expert	Novices
Match similar	92.12%	74.55%
Distracter	99.32%	44.82%
Non-similar distracter	100%	77.03%

a.Given a pair of matched prints, what is the probability that an expert failed to identify the match?

b. Given a pair of matched prints, what is the probabilitythat a novice failed to identify the match?

c. Assume the study included 10 participants, 5 experts and 5 novices. Suppose that a pair of matched prints was presented to a randomly selected study participant and the participant failed to identify the match. Is the participant more likely to be an expert or a novice?

Short answer

(a) The probability is 0.079.

(b) The probability is 0.2545.

(c) The participant more likely to be novice.

Step-by-step solution

Given information

The data is provided in the table,

Let

P-The professional to make the best decision

B-The beginner to make the right decision

C-The condition that is connected or matched

S-The same distracter condition

N-The non-similar distracter.

The probability that an expert failed to identify the match.

$$\begin{gathered} P\left(\frac{P^c}{C}\right)=1-P\left(\frac{P}{C}\right) \\ =1-0.9212 \\ =0.079 \end{gathered}$$

So, the probability is 0.079.

The probability that a novice failed to identify the match

$$\begin{gathered} P\left(\frac{S^c}{C}\right)=1-P\left(\frac{S}{C}\right) \\ =1-0.7455 \\ =0.2545 \end{gathered}$$

Hence, the probability is 0.2545.

Is the participant more likely to be an expert or a novice.

From the results of part (a) and (b), its clear that the participant more likely to be a novice.

Therefore, the contestant is more likely to be inexperienced.