Is reciprocity really outcome-based? A second look at gift-exchange with random shocks

By means of a laboratory experiment, Rubin and Sheremeta (Manag Sci 62(4):985–999, 2016), study a bonus-version of the gift-exchange game, including two treatment variations. First they vary whether the effort provided by the agent directly translates into output for the principal, or whether it is distorted by a shock. Second, for the condition with a shock they vary whether the shock is observed by the principal, or not. The authors’ main findings are that (1) the introduction of an unobservable shock significantly reduces welfare; and (2) informing the principal about the size of the shock does not restore gift-exchange. In a replication study we largely reproduce finding (1), but we fail to confirm finding (2). Our data suggests that small behavioral differences in the initial rounds lead to a hysteresis effect that is responsible for the differences in results across studies. Electronic supplementary material The online version of this article (10.1007/s40881-017-0041-2) contains supplementary material, which is available to authorized users.

Standard errors in parenthesis are based on 9 indep. observations; stars for significance according to Mann-Whitney U-tests, based on 9 indep. observations: * p < 0.10, * * p < 0.05, * * * p < 0.01    Standard errors in parentheses are clustered on the group level and calculated via bootstrap; * p < 0.10 , * * p < 0.05, * * * p < 0.01. 'Effort > des. effort' is a dummy = 1 if effort > des. effort, zero otherwise; 'Effort < des. effort' is a dummy = 1 if effort < des. effort, zero otherwise. Inv. period runs from 1 to 1/10.  Standard errors in parentheses are clustered on the group level and calculated via bootstrap; * p < 0.10, * * p < 0.05, * * * p < 0.01. Inv. period runs from 1 to 1/10. We ask you to not talk to other participants and to use only the resources and devices that are provided by the conductors of the experiment. Please switch off all electronic devices.
In addition, at the computer you are only allowed to use features that are necessary for the experiment. If you do not comply with these rules, you won't be paid in this experiment and you are not allowed to participate in any further experiments.
The currency used in the experiment is tokens. Tokens will be converted to Euros at a rate of 10 tokens to 1 Euro. You have already received a e11.00 participation fee. Your earnings from the experiment will be incorporated into your participation fee. At the end of today's experiment, you will be paid in private and in cash.
The experiment consists of two parts. Together, both parts will last for around 75 minutes.
The two parts of the experiment are completely independent from each other. That is, your payment for part x only depends on decisions that you take in part x, and does not depend on decisions you take in the other part of the experiment. At the beginning of each part you receive the corresponding instructions. We will read the instructions out loud and will give you time for questions.
Thank you a lot for your attention and for participating in today's experiment.

YOUR ROLE ASSIGNMENT
This part consists of 10 periods. Each period, you will be randomly and anonymously placed into a group which consists of two participants: participant A and participant B. At the beginning of the first period you will be randomly assigned either as participant A or participant B. You will remain in the same role throughout part 1 of the experiment. So, if you are assigned as participant B then you will stay as participant B throughout the entire part 1. Each consecutive period you will be randomly re-grouped with another participant of opposite assignment. So, if you are participant B, each period you will be randomly re-grouped with another participant A.
Each period will proceed in three stages.

STAGE 1
In stage 1, participant A will choose a reward (any integer number between 0 and 100) and a desired effort (any integer number between 0 and 14) for participant B.
An example of the stage 1 decision screen for participant A is shown below.
STAGE 2 On the screen, participant B is shown the reward and the desired effort chosen by participant A. Then, participant B will choose an effort level (any integer number between 0 and 14).
An example of the stage 2 decision screen for participant B is shown below.
For each effort level chosen by participant B there is an associated cost of effort. The cost of effort can be found in the following table: Note that as effort rises from 0 to 14, costs rise At the end of each period, the computer will calculate individual earnings.
An example is shown on the following picture.
Once your earnings are displayed on the outcome screen as shown below you should record your earnings for the period on your Personal Record Sheet under the appropriate heading.

IMPORTANT NOTES
Remember you have already received a e11.00 participation fee. In part 1 of the experiment, depending on a period, you may receive either positive or negative earnings. At the end of part 1 we will randomly select 1 out of 10 periods for actual payment and convert the income thereof to a payment in Euros. If the earnings are negative, we will subtract them from your total earnings. If the earnings are positive, we will add them to your total earnings. Are there any questions?
Control questions (implemented in z-Tree)

Personal Record Sheet
This sheet is for yourself, to record the earnings you have for each period.
You are participant A / B (circle one) Period Step 1 Step 1 Step 2 Step 2 Step 2 Step 3 Income from Income Wage Desired Perform. Effort Random Adj. decisions/beliefs period effort number 1 2 3 . . .

Part 2
On your computer screen you will see a square composed of 100 numbered boxes, like shown below.
Behind one of these boxes hides a mine; all the other 99 boxes are free from mines. You do not know where this mine lies. You only know that the mine can be in any place with equal probability.
Your task is to decide how many boxes to collect. Boxes will be collected in numerical order. So you will be asked to choose a number between 1 and 100.
At the end of the experiment we will randomly determine the number of the box containing the mine. If you happen to have harvested the box where the mine is located -i.e. if your chosen number is greater than or equal to the drawn number -you will earn zero. If the mine is located in a box that you did not harvest -i.e. if your chosen number is smaller than the drawn number -you will earn in euro an amount equivalent to the number you have chosen.
In the next screen we will ask you to indicate how many boxes you would like to collect. You confirm your choice by hitting 'OK'.