Sample evaluation

As can be seen by the results stated above, we were able to support the findings of Tversky & Kahnemann (1974) and the prediction that an anchor influences a person’s estimate of a value. They found a much lower difference between the two groups than we did.  The difference between the two medians in the original study was 1738; in our study, it was a difference of 9202.50. This could be because our participants were younger and may not have as much conceptual understanding of mathematics. This means that we support the Dual Process Model and the use of system 1 thinking. Since the students didn't have much mathematical understanding, they relied on the anchor to make an estimate.

One of the strengths of our procedure was that we had the participants practice estimation first so that we could rule out that they didn’t understand instructions.  In addition, we had them answer the key question on the back of the paper so that they did not see the previous numbers on the other side of the paper.  We did this so that those numbers did not influence their estimate.  However, a limitation of the procedure is that we probably should have carried out a distractor task - such as reciting the alphabet backward – between tasks.  We cannot rule out that the memory of the previous estimates may have influenced their final response.

There were also several variables that could not be controlled.  For example, it is not possible to know to what extent the participants were trying to quickly calculate the response and whether they were really estimating.  We also do not know if they read the equation from left to right or right to left. During the debriefing, the participants did not show that they knew the goal of the study, but some indicated that they found it uninteresting.  This may have resulted in a high variation of the responses. 

A limitation of the design was that we used an independent samples design. Our differences may be due to participant variability. We do not know how many of the participants have experience with factorials or with estimating values. It may be more appropriate to first test the students for their ability to estimate the values of equations or their knowledge of factorials and then eliminate them from the sample if necessary. The strength was it allowed us to use the same equation with both groups and they did not guess the hypothesis.

Although the strength of the sample was that it was easily obtained, there were limitations of the sample. It is difficult to generalize our findings as the sample was made up of only grade 9 maths students. Older participants or participants with lower math abilities may not demonstrate the same results.

One modification for future replication would be to create a more realistic context.  Rather than simply giving them a math problem, several studies give suggested prices for goods. The participants then have to determine what a fair price would be. If anchoring works, then when the given price should have an effect on the concept of a “fair price.” We would also try to match the math abilities of both groups to make sure that this does not have an effect on the difference in estimates.

From our study, we are able to conclude that in a sample of grade 9 mathematics students, the value of the anchor in a math equation affects the estimate of the answer to the equation.

NB: The entire sample in this chapter is only 1660 words in length.  The maximum word count is 2200. Many ideas could and should be added to the evaluation, this is only used as an example of the way to approach the writing of the IA.