Grappling with procrastination for over 30 years.

Context & Findings: The study utilized both between-subjects and within-subjects designs to test the "Cross-modal effect." The results consistently showed that when the outcomes being compared are "Cross-modal" (different), people tend to discount the future less than when outcomes are "Uni-modal" (same).

Theoretical Contribution: These results support the theory of "Attentional Dilution". When the outcome types differ between options, the decision involves two distinct attributes: the type of outcome and the delay. As a result, people focus less on the delay compared to uni-modal decisions (where only time differs), leading to more patient decisions in both the US and Japan.

Yamamoto, S., McDonald, R. and Read, D. "Does cross-modal discounting generalize to non-WEIRD cultures? A comparison of the USA and Japan", arXiv Working Paper No. 2511.23126.

Figure 1 illustrates the preference patterns we observed: the seller's willingness to accept remains relatively constant, while the buyer's willingness to pay is consistently discounted for future transactions across three items—a poster, an autographed CD, and a mug.

Implications: Many daily transactions are deferred to the future. For instance, you might purchase an item online and receive it later, agree to sell something on an online flea market now and make the transaction at a later date, or pay in advance to book a hotel, among other scenarios. Our findings suggest that the gap between the seller's willingness to accept and the buyer's willingness to pay increases when the transaction is delayed. Consequently, agreements on transactions are less likely to be reached when they are scheduled for the future.

Yamamoto, S. and Navarro-Martinez, D. (2022) "The Endowment Effect in the Future: How Time Shapes Buying and Selling Prices", Judgment and Decision Making, 17, 988-1014.

In response, we developed a novel two-stage experiment using a 2 x 2 design to compare outcomes (money and effort) across domains (pleasant and unpleasant). This method allowed for the incentivization of all decisions, including those involving future monetary losses. Our study reveals sign-dependent preferences, indicating varying levels of impatience depending on whether the experiences are pleasant or unpleasant, and whether they relate to monetary or effort-based decisions.

Yamamoto, S., Shiba, S. and Hanaki, N. "Outcome- and sign-dependent time preferences: An incentivized intertemporal choice experiment involving effort and money", ISER Discussion Papers No.1230.

Figure 2 displays screenshots of the first questions in the No frame and Loan frame treatments (Study 1). The total outcomes are the identical between these two frames (£24 today and £24 in 2 months in total for the left option, and £16 today and £32 in 2 months in total for the right option). Subjects tended to ignore the common payments between the options when making decisions, resulting in different preferences between the two frames.

Implications: Our findings have practical implications, showing that time preferences can be influenced without changing total outcomes. This insight is applicable across various fields. For example, consider two hypothetical stocks Stocks A and B, which yield identical total returns. Both generate identical dividends, whereas their prices fluctuates differently over time. Our findings suggest that individuals can make irrational decisions because they tend to ignore the identical dividends component and focus solely on variable stock price.

Yamamoto, S. and Shiba, S. "Framing Effects on Time Preferences: The Impact of Investment and Loan Contexts in Intertemporal Choices", ISER Discussion Papers No.1237.

In the experiment, some leaners studied English vocabulary either individually (Single condition) while others studied with a learning partner. Figure 3 shows the number of studied words in Study 1. Compared to the Single Condition, the number of studied words was significantly lower leaners had a similarly skilled and low-perseverance partner (Similar-quitter condition).

Further analysis indicated that the negative peer effects predominantly originated from participants with lower levels of motivation. Additionally, it was shown that social proximity could foster positive effects when peers possess similar skills and higher perseverance levels. Our findings suggest that the strategic pairing of learners with appropriate partners is crucial for diminishing negative peer effects and enhancing positive peer influences.

Yamamoto, S., Iwatani, S and Shimazu, K. "When Learning Together Goes Wrong: Negative Peer Effects in Online Learning", ISER Discussion Papers No.1242.