Include all the information you can think of that supports your recommendations, and also evidence against your recommendations — because you are going to have to deal with this information somehow, so you cannot just ignore it.
Try to collect information broadly, from several different sources, not just the project you are working on. Don ’ t worry about the order of your list of information, or whether it is quantitative or merely anecdotal, at this point. Just list everything that you can think of: basically all the information you can think of that is relevant to your solution.
The rest of this chapter will explain in detail:
What kinds of evidence to include to strengthen the persuasiveness of your presentation
What kinds of evidence are likely to weaken your presentation and therefore should be avoid ed
Where to look for evidence
MARSHALLING YOUR EVIDENCE 59
prove that the thing you are talking about indeed exists. One company frequently used a conceptual chart to communicate their approach to change management. The chart showed a line of how sales would evolve through the various stages of a change manage- ment program. My recommendation to them was that the chart would be made more powerful by adding the details of one or two case studies to it. So instead of just saying, “ Here, conceptually, is how a company ’ s sales revenues will evolve through the stages of a change program, ” you can also say, “ And here it is in practice, with the results we saw at IBM and at Microsoft, ” for example.
Include a Variety of Different Types of Evidence
As you gather your evidence, be sure to include different types of evidence, arguments, and support for your recommendations. Use both qualitative and quantitative data, mul- tiple arguments, causal arguments, evidence that is inherently persuasive, evidence about the problem, and evidence against your recommendations.
Quantitative and Qualitative Data Use both quantitative and qualitative data. While quantitative (numerical) data may seem specifi c and concrete, and particularly rele- vant for the detail - oriented members of your audience, it can actually be quite abstract.
When you say that 4 percent of your products had some kind of quality defect this past month, that number “ 4 percent ” may seem like a specifi c detail, but actually it is a gen- eralization across many observations, perhaps thousands of them. To add more detail, use qualitative data also: examples, anecdotes, cases - in - point. Perhaps a diagram or — better (because more real) — a photograph of a fl awed product. Or, best and most real of all, if the group is small enough and the product is portable, bring an example of a fl awed product to the meeting, to serve as a three - dimensional data sample. Qualitative data reinforces your quantitative data: where the latter summarizes thousands of obser- vations, the former zooms in on just one or two of those observations. It gives your audi- ence comfort that your statistics are not lying, by showing them one or more of your actual observations.
Multiple Arguments The more evidence and arguments you include in your presenta- tion, the more likely your audience is to be persuaded. This tends to be true whether or not your audience is highly concerned about the issue being discussed. When people are more concerned about the issue at hand, using more arguments tends to increase per- suasion by providing more supportive information on which to make a decision. When people are not so concerned, however, the greater number of arguments also is more effective, because it gives the impression (correctly) of a strong case being made. 1
Causal Arguments Causal arguments — when you show how one things leads to or causes another — are particularly effective. When you explain why or how your recom- mended actions will lead to the results they want, people fi nd this more convincing than when you just provide evidence that your recommendations do lead to the desired results.
People are more willing to be convinced when they understand not just that something will succeed, but also why or how it will succeed. 2
1 Petty & Cacioppo (1984) ran an experiment in which students were presented with different versions of a message with different numbers of arguments, and found that increasing the number of arguments increased the chance of agreement with the message.
1 Petty & Cacioppo (1984) ran an experiment in which students were presented with different versions of a message with different numbers of arguments, and found that increasing the number of arguments increased the chance of agreement with the message.
2Research experiments by Slusher and Anderson (1996) indicate that causal arguments or explanations are more persuasive than statistical evidence.
2Research experiments by Slusher and Anderson (1996) indicate that causal arguments or explanations are more persuasive than statistical evidence.
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For example, don ’ t just say “ our research shows that serif fonts (e.g., Times Roman) are more readable than sans serif fonts (e.g., Arial), ” also say, “ because the little serifs serve as cues to the brain, allowing it to process the letters more quickly. ”
EVIDENCE THAT IS INHERENTLY PERSUASIVE
Cialdini (2001), summarizing several decades of psychology research on persuasion, draws a number of conclusions about how people are persuaded. Based on these conclusions, we can identify additional types of evidence that should be inherently persuasive: quotes from authority fi gures; information about the consistency of your proposals; information about what others are doing that is similar to your proposals; and information about the scarcity of the opportunity.
People are more likely to be persuaded by authority fi gures, so whenever you can, cite respected experts, such as analysts, academics, or industry experts, whose opinions support your recommendations
There is a desire among most people “to be and look consistent within their words, beliefs, attitudes, and deeds” (Cialdini, 2001, p. 95), so if your recommendations are consistent with previous actions that your audience has taken, or aligned with a strategy that they have committed to, be sure to inform them of this.
“[O]ne important means that people use to decide what to believe or how to act in a situation is to look at what other people are believing or doing there” (Cialdini, 2001, p. 140), so if other organizations are also doing what you are recommending, be sure to include this fact in your list of evidence.
“People assign more value to opportunities when they are less available” (Cialdini, 2001, p. 231), so if the opportunity that you are proposing is scarce or limited in any way, mention this also.
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Evidence About the Problem Include evidence about the existence and magnitude of the problem that you are addressing, not just about the solution you are offering. The less likely that your audience is to believe in the existence of, or be concerned by, the prob- lem you are focusing on, the more evidence about the problem you should include.
Evidence Against Your Recommendations As counter - intuitive as this may seem, you should also include evidence that supports competing, alternative solutions and evidence against your own solution. Research consistently shows that presenting a “ two - sided ” message (where arguments from both sides, in favor and against, are included) is more persuasive than a “ one - sided ” message (where only arguments on one side are included). 3 In addition to mentioning the opposing arguments, you should also refute them con- vincingly; mentioning them without refuting them can be worse than not mentioning them at all, in terms of persuasion. But even merely mentioning the opposing arguments, so long as they are serious, not trivial, arguments will increase your credibility with the audience because they see that you are trying to provide them with a comprehensive view of the issue, rather than just selecting the information that supports your case.
In refuting the opposing arguments, be careful about disparaging or trying to get your audience to disregard the contrary information, because doing so can increase their inter- est in it. People tend to be more attracted to what they are told to avoid. For example, when some counties in Florida banned phosphate detergents in the 1970s, consumers in those counties rated the same phosphate detergents more highly than consumers in counties where they were not banned. 4
3 See Allen ’ s (1998) meta - analysis of research on one - versus two - sided messages. Pechmann ’ s (1992) research indicates that advertising that admits a serious negative feature is associated with stronger credibility.
3 See Allen ’ s (1998) meta - analysis of research on one - versus two - sided messages. Pechmann ’ s (1992) research indicates that advertising that admits a serious negative feature is associated with stronger credibility.
4See Mazis (1975). But legal research is mixed on this point.
Research by Broeder (1959) and Wolf and Montgomery (1977) found that judges’ instructions to ignore certain evidence can lead jurors to give that evidence more consideration, but other studies contradict these fi ndings.
4See Mazis (1975). But legal research is mixed on this point.
Research by Broeder (1959) and Wolf and Montgomery (1977) found that judges’ instructions to ignore certain evidence can lead jurors to give that evidence more consideration, but other studies contradict these fi ndings.
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MARSHALLING YOUR EVIDENCE 61
What we have here is another instance of the tactic of “ stealing thunder, ” which we dis- cussed in Chapter 3 . When you are the fi rst to bring up negative information about your argument, your argument is viewed more favorably than if someone else fi rst brought up the negative information. Remember that if you do not bring up the contrary arguments, you run the risk that someone in your audience will, and this can be quite damaging to your presentation.
New and Different Information
Wherever possible, be sure to include information that is new and different. This is par- ticularly true for presentations that are providing an update on a project or reporting on an ongoing research study (such as a market tracking study). In such cases, you will often have too much information. Focus on information that is new or unusual; if this quarter ’ s tracking study fi nds an increased interest in organic foods among youth, for example, make that the center of your presentation. 5
Try to avoid repeating the same, tired old “ facts ” that everyone else quotes. For example, anyone giving a presentation about interpersonal communication usually quotes the same old “ fact ” that 93 percent of all communication is non - verbal. Sometimes it is worth doing some digging. You may fi nd that the established “ fact ” is in fact false — we noted in the Introduction that this is indeed the case with the “ 93 percent non - verbal ” statis- tic. The information that the well - known “ fact ” is in fact false is then itself a newsworthy piece of information that you can include that will help your presentation stand out.